abstract

Upcycling / Downcycling

Plastic waste electronics

Pyrolysis

thermal cracking

Ecodesign

Addition of Materials for Depolymerization

Energy production

Extending the producer/consumer responsibility

Business models

bioplastics and
biodegradable plastics

Assessment and prediction model

Machanical process

Construction

Industry 4.0

rayyan-671783915

How does the global plastic waste trade contribute to environmental benefits: Implication for reductions of greenhouse gas emissions?

JOURNAL OF ENVIRONMENTAL MANAGEMENT

Liu, Z and Liu, WL and Walker, TR and Adams, M and Zhao, JJ and Liu, Zhe and Liu, Weili and Walker, Tony R. and Adams, Michelle and Zhao, Jingjing

24-28 OVAL RD, LONDON NW1 7DX, ENGLAND

Plastic waste pollution has been identified as a serious global issue, posing environmental risks in terms of massive waste generation, ocean pollution, and increases in greenhouse gas (GHG) emissions. Despite documented environmental impacts, it remains debatable whether the global plastic waste trade (GPWT) for reutilization and recycling, as part of the global circular economy (CE), has historically contributed to environmental benefits. To investigate if historical GPWT has contributed to environmental benefits in terms of reductions of GHG emissions, this study analyzed GPWT between China and trading countries through their trajectories, characteristics and driving forces of reductions of GHG emissions between 1992 and 2017. Results indicated an increasing trend of reductions of GHG emissions in GPWT between China and trading countries over 25 years. A net reduction of 8.27 million metric tons carbon dioxide equivalent (CO2e) was observed in 2012, nearly 84 times levels observed in 1992. Policy implications after China?s recent ban of imports of GPWT in December 2017 and recent changes of GPWT to other Asian countries are discussed. Dramatic changes in sustainable approaches to GPWT for reutilization and recycling are required.

rayyan-671783917

Life cycle environmental impacts of chemical recycling via pyrolysis of mixed plastic waste in comparison with mechanical recycling and energy recovery

SCIENCE OF THE TOTAL ENVIRONMENT

Jeswani, H and Kruger, C and Russ, M and Horlacher, M and Antony, F and Hann, S and Azapagic, A and Jeswani, Harish and Krueger, Christian and Russ, Manfred and Horlacher, Maike and Antony, Florian and Hann, Simon and Azapagic, Adisa

RADARWEG 29, 1043 NX AMSTERDAM, NETHERLANDS

A large portion of plastic produced each year is used to make single-use packaging and other short-lived consumer products that are discarded quickly, creating significant amounts of waste. It is important that such waste be managed appropriately in line with circular-economy principles. One option for managing plastic waste is chemical recycling via pyrolysis, which can convert it back into chemical feedstock that can then be used to manufacture virgin-quality polymers. However, given that this is an emerging technology not yet used widely in practice, it is not clear if pyrolysis of waste plastics is sustainable on a life cycle basis and how it compares to other plastics waste management options as well as to the production of virgin plastics. Therefore, this study uses life cycle assessment (LCA) to compare the environmental impacts of chemical recyding of mixed plastic waste (MPW) via pyrolysis with the established waste management alternatives: mechanical recycling and energy recovery. Three LCA studies have been carried out under three perspectives: waste, product and a combination of the two. To ensure robust comparisons, the impacts have been estimated using two impact assessment methods: Environmental footprint and ReCiPe.The results suggest that chemical recycling via pyrolysis has a 50% lower climate change impact and life cycle energy use than the energy recovery option. The climate change impact and energy use of pyrolysis and mechanical recycling of MPW are similar if the quality of the recydate is taken into account. Furthermore, MPW recycled by pyrolysis has a significantly lower climate change impact (-0.45 vs 1.89 t CO2 eq.it plastic) than the equivalent made from virgin fossil resources. However, pyrolysis has significantly higher other impacts than mechanical recycling, energy recovery and production of virgin plastics. Sensitivity analyses show that some assumptions have notable effects on the results, including the assumed geographical region and its energy mix, carbon conversion efficiency of pyrolysis and recyclate quality. These results will be of interest to the chemical, plastics and waste industries, as well as to policy makers. (C) 2021 The Author(s). Published by Elsevier B.V.

rayyan-671783919

A simulation-based analysis for the performance of thermal solar energy for pyrolysis applications

INTERNATIONAL JOURNAL OF ENERGY RESEARCH

Lameh, Mohammad and Abbas, Ali and Azizi, Fouad and Zeaiter, Joseph

111 RIVER ST, HOBOKEN 07030-5774, NJ USA

Solid plastic waste presents a perplexing waste disposal challenge, which has increased in importance due to increasing demand for plastic products over the last century. Chemical recycling approaches such as pyrolysis, allow the conversion of the polymer waste into value-added fuels and chemicals. Pyrolysis provides potential pathways for the circular economy of plastics, especially because of the potential to produce feedstock chemicals for remanufacturing of new plastic products. The high temperatures required to operate the pyrolysis process, however, affect its environmental performance due to the indirect emissions generated when supplying the process with energy. This drawback can be overcome by using renewable energy sources. This work investigates the integration of concentrated solar power (CSP) with the pyrolysis of high-density polyethylene (HDPE), to evaluate the process environmental performance. A mechanistic model is used to describe the pyrolysis reaction kinetics, and is integrated into an Aspen Plus flowsheet model to describe the entire pyrolysis process. System Advisor Model was used to model the solar-thermal process system, which supplies the process with the required heat throughout the year. Process simulations show that operating the pyrolysis reactor at 520 degrees C would convert 78%wt of HDPE to light gases and liquid fuels. The process requires 752 kWh(th)/ton-HDPE, out of which 82% is used to heat the feed and operate the distillation column. Model simulations showed drastic reductions in fossil fuel usage, with solar energy capacity providing 52.5% of the pyrolysis process annual heat demand. Model-based optimization analysis showed that 72.6% of the pyrolysis plant thermal requirements could be generated via solar energy during the summer, with a CO2 avoidance potential of about 67 kg/ton-HDPE.

rayyan-671783920

Enhancement of the fatigue life of recycled PP by incorporation of recycled opaque PET collected from household milk bottle wastes

WASTE MANAGEMENT

Tramis, O and Garnier, C and Yus, C and Irusta, S and Chabert, F

THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND

Opaque PET (Polyethylene terephthalate) was recently introduced as a dairy packaging, mainly for milk
bottles. Opaque PET, obtained as PET filled with mineral nanoparticles, allows for a reduction of bottles’
thickness, thus a cost reduction for industrials. For this reason, the use of opaque PET is steadily increasing.
However, its recyclability is nowadays an issue: although the recycling channels are well established
for transparent PET, the presence of opaque PET in the household wastes weakens the existing recycling
channels. Besides, many initiatives are launched in Europe to turn wastes into resources, as one key to a
more circular economy. One of the biggest challenges is an efficient sorting of the plastic solid wastes
since the PET is not miscible with other plastics such as polypropylene (PP) from the bottle caps and polyethylene
(PE) from the other milk bottles.
In this work, the mechanical properties of uncompatibilized blends of opaque PET (rPET-O) with recycled
polypropylene (rPP) have been studied; both are collected from household wastes. The tensile properties
and the fatigue life of rPP, monitored by in-situ digital image correlation and in-situ infrared
thermography, are increased by the incorporation of rPET-O. rPET-O/rPP blends may be substituted to
rPP for similar applications, with no need to sort the caps from the bottles. Thus, as a concept, the incorporation
of opaque PET into the PP recycling sector may be a new route to absorb some of the growing
amounts of opaque PET.

rayyan-671783922

Green strategies for microplastics reduction

CURRENT OPINION IN GREEN AND SUSTAINABLE CHEMISTRY

Calero, M and Godoy, V and Quesada, L and Martin-Lara, MA and Calero, Monica and Godoy, Veronica and Quesada, Lucia and Angeles Martin-Lara, Maria

RADARWEG 29, 1043 NX AMSTERDAM, NETHERLANDS

Currently, one of the biggest challenges is to reduce plastics contamination worldwide. In this scenario, some political, economic and social factors play a very important role in implementing efficient processes to control the plastic waste problem. In this work, some of the most recent advances in this field are presented. The eco-design of plastic products, the improvement of legislation for the manufacture, recycling and use of alternative materials, as well as for the intentional addition of microplastics to products, the development and research in biodegradable plastic and bioplastics, and the improvement of wastewater treatment facilities are important tools to reduce microplastic contamination and promote the circular economy.

rayyan-671783923

Municipal Solid Waste Mass Balance as a Tool for Calculation of the Possibility of Implementing the Circular Economy Concept

ENERGIES

Wielgosinski, Grzegorz and Czerwinska, Justyna and Szufa, Szymon

ST ALBAN-ANLAGE 66, CH-4052 BASEL, SWITZERLAND

Municipal waste management system modeling based on the mass balance of individual waste streams allows us to answer the question of how the system will react to organizational changes, e.g., to the expected reduction in the amount of plastics or the introduction of a deposit for glass and/or plastic packaging. Based on the data on Polish municipal solid waste and the forecast of changes in its quantity and composition, as well as demographic data, a balance model was prepared to assess the impact of introducing higher and higher levels of recycling, in accordance with the circular economy assumptions on the waste management system. It has been shown that, for the Polish composition of municipal waste, even if the assumed recycling levels of individual streams are achieved, achieving the general target level of 65% recycling in 2025/30 may not be feasible. The possibility of achieving a higher level of recycling will be possible due the introduction of selective ash collection from individual home furnaces, while the impact of reducing the amount of plastics or introducing a deposit on packaging is minimal. The calculations also showed that, to complete the waste management system in Poland, we need at least 3.5 million Mg/year of incineration processing capacity and the present state (approx. 1.3 million Mg/year) is insufficient.

rayyan-671783926

Clarifying the in-situ cytotoxic potential of electronic waste plastics

CHEMOSPHERE

Shi, Pujiang and Wan, Yan and Grandjean, Agnes and Lee, Jong-Min and Tay, Chor Yong

THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND

Plastics in waste electronics (E-plastics) account for approximately 20% of the entire global electronic waste (E-waste) stream. Most of the E-plastics are not recycled as the presence of toxic additives (e.g. heavy metals, brominated flame retardants (BFRs), antimony, etc.) have associated environmental and health concerns. However, the majority of the studies are focused on quantitative assessment of the toxic constituents in E-plastics, while empirical information regarding the potential toxic effects in humans is largely lacking. To gain a deeper appreciation into the toxicological profile of E-plastics, in situ time dependent exposures of 6 different human cell lines to a panel of 8 representative E-plastics recovered from liquid crystal displays (LCD), keyboards, screen frames, and wire insulators were conducted. Although several hazardous elements (e.g. Pb, As, Sb, Zn, Cu, etc) were detected at concentrations that far exceed the limit values permitted by the Restriction of Hazardous Substances Directive and EU Directives in the panel E-plastics, in-depth analysis of the 144 unique cell viability data points and live-dead staining experiments suggest that the acute and sub-chronic toxic effects of E-plastics in direct contact with human cells are negligible. These observations agreed with the inductively coupled plasmaoptical emission spectrometry data, which revealed that leaching of these toxic additives into the biological milieu is not sufficiently high to trigger a cytotoxic response up to a continuous culture period of 2 weeks. The novel insights gained from this study are posited to further clarify the uncertainty associated with the safety and circular economy implementation of E-plastics. (C) 2020 Elsevier Ltd. All rights reserved.

rayyan-671783932

Advancing Plastic Recycling by Wet-Mechanical Processing of Mixed Waste Fractions

PROCESSES

Schwabl, Daniel and Bauer, Markus and Lehner, Markus

ST ALBAN-ANLAGE 66, CH-4052 BASEL, SWITZERLAND

In this paper, an arc was drawn over ten years of research activities from three chairs of the Montanuniversitaet Leoben, as well as industrial partners. The superior objective of this research effort was to develop a wet-mechanical process for the recovery of polyolefin concentrates (90 wt% polyolefins) from mixed waste fraction for use in chemical recycling and to advance this new technology to commercial maturity. As a bridge technology, it would close the gap between state-of-the-art dry processing of mixed plastic waste materials and chemical plastic recycling via thermo-chemical conversion. The methods used were mainly tested in a lab-scale plant with a throughput capacity of 50 to 200 kg/h depending on the bulk density of the used feedstock. Further studies for the treatment and usage of the main products and by-products, as well as chemical analyses of them, were completed during the investigation. Within these series of tests, polyolefin concentrates, which satisfied the requirements for chemical recycling, could be recovered. With these data, a concept for an industrial pilot plant was developed and evaluated from an economic point of view. According to this evaluation, the realization of such an industrial pilot plant can be recommended.

rayyan-671783961

Recirculation potential of post-consumer /industrial bio-based plastics through mechanical recycling - Techno-economic sustainability criteria and indicators

POLYMER DEGRADATION AND STABILITY

Briassoulis, Demetres and Pikasi, Anastasia and Hiskakis, Miltiadis

THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND

The sustainable circular bioeconomy turns biogenic waste and residues into renewable resources to produce added value bio-based materials. According to the recent, Circular Economy Package EU legislation, mechanical recycling offers the best alternative EoL option for bio-based plastics in a complementary way with chemical recycling, with the latter taking over materials inadequate to be mechanically recycled. Techno-economic sustainability analysis (TESA) criteria and indicators to assure the feasibility and viability of mechanical recycling of post-consumer bio-based plastics, and the recirculation potential of the recovered material, are proposed based on the evaluation and synthesis of research results selected though a critical literature review. Organic recycling is considered as a preferred EoL option for post-consumer biodegradable bio-based plastics only when these products are found to be non-recyclable by the proposed TESA criteria. Environmental and social sustainability criteria, that constitute the other two pillars of sustainability, are not considered in the present work, but need to be included to complete the sustainability assessment of any End of Life (EoL) option. The proposed technoeconomic sustainability criteria for mechanical recycling include: a) Mechanical recyclability, b) Economic viability, c) Common environmental/techno-economic criteria and also d) Recirculation potential of the materials recovered. Specific indicators are proposed as metrics for assessing the corresponding criteria. (C) 2020 Elsevier Ltd. All rights reserved.

rayyan-671783986

Ecotoxicity of Plastics from Informal Waste Electric and Electronic Treatment and Recycling

Butturi, MA and Marinelli, S and Gamberini, R and Rimini, B and Butturi, Maria Angela and Marinelli, Simona and Gamberini, Rita and Rimini, Bianca

ST ALBAN-ANLAGE 66, CH-4052 BASEL, SWITZERLAND

Plastic materials account for about 20% of waste electrical and electronic equipment (WEEE). The recycling of this plastic fraction is a complex issue, heavily conditioned by the content of harmful additives, such as brominated flame retardants. Thus, the management and reprocessing of WEEE plastics pose environmental and human health concerns, mainly in developing countries, where informal recycling and disposal are practiced. The objective of this study was twofold. Firstly, it aimed to investigate some of the available options described in the literature for the re-use of WEEE plastic scraps in construction materials, a promising recycling route in the developing countries. Moreover, it presents an evaluation of the impact of these available end-of-life scenarios on the environment by means of the life cycle assessment (LCA) approach. In order to consider worker health and human and ecological risks, the LCA analysis focuses on ecotoxicity more than on climate change. The LCA evaluation confirmed that the plastic re-use in the construction sector has a lower toxicity impact on the environment and human health than common landfilling and incineration practices. It also shows that the unregulated handling and dismantling activities, as well as the re-use practices, contribute significantly to the impact of WEEE plastic treatments.

rayyan-671784006

Assessing scaling effects of circular economy strategies: A case study on plastic bottle closed-loop recycling in the USA PET market

RESOURCES CONSERVATION AND RECYCLING

Lonca, Geoffrey and Lesage, Pascal and Majeau-Bettez, Guillaume and Bernard, Sophie and Margni, Manuele

RADARWEG 29, 1043 NX AMSTERDAM, NETHERLANDS

The Circular Economy (CE) movement is inspiring new governmental policies along with company strategies. This led to the emergence of a plethora of indicators to quantify the "circularity" of individual companies or products. Approaches behind these indicators builds mainly on two implicit assumptions. The first is that closing material loops at product level leads to improvements in material efficiency for the economy as a whole. The second assumption is that maximizing material circularity contributes to mitigate environmental impacts. We test these two assumptions at different scales with a case study on the circularity of PET in the USA market. The Material Circularity Indicator (MCI) reveals that closing the material loops at the product level increases material circularity in one brand and in the USA plastic bottle market but not in the USA PET market as a whole. Life Cycle Assessment (LCA) results reveal that increasing closed loop recycling of PET bottles is environmentally beneficial from product-level assessment scope. When expanding the scope to the whole PET market, recycling PET into film, fiber and sheet industrial sectors results being more material efficient and environmental preferable, unless the postconsumer reclamation rate is significantly improved. Thus, we demonstrate that adopting a systemic approach for CE assessment is essential

rayyan-671784014

Green chemistry and the plastic pollution challenge: towards a circular economy

GREEN CHEMISTRY

Sheldon, Roger A. and Norton, Michael

THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND

The linear economy for plastic packaging, which currently leads to excessive carbon dioxide emissions and leakage into the environment, needs to be reformed to a greener circular model which is resource efficient and environmentally benign. This requires a system-wide redesigning of rules and incentives that apply to the plastics value chain, from product design to recycling and end-of-life options. This article identifies areas where green chemistry can contribute. Substituting plastics derived from fossil resources, with bio-based alternatives from renewable resources can reduce emissions of greenhouse gases, produce plastics that are easier to recycle to the virgin polymer and, at the end of their useful life, biodegrade in the environment. The underpinning chemo- and biocatalytic technologies for the production and recycling of plastics are reviewed and priorities suggested for future development.

rayyan-671784048

Plastics as a materials system in a circular economy

PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES

Bucknall, DG and Bucknall, David G.

6-9 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND

Plastics have transformed our modern world. With a range of outstanding properties, they are used in an ever-widening range of applications. However, the linear economy of their use means that a large volume of plastics is discarded after use. It is believed that approximately 80% of the estimated total 6.3Bt of plastics ever produced have been discarded, representing not only a huge loss of valuable resources, but mismanaged waste is also the origin of an ever-increasing environmental disaster. Strategies to prevent loss of materials resources and damage to the environment are elements of a circular plastics economy that aims to maintain plastics at their highest value for the longest time possible and at the same time improve the economy and prevent detrimental environmental impact. The latter in particular is driving recent changes in policies and legislation across the world that are rapidly being introduced in order to solve these environmental issues. The achievement of a circular economy will require not only innovative technical developments, but also major economic investment and changes to business practice coupled with significant changes in social behaviour. This paper summarizes the complex and highly interrelated technical issues and provides an overview of the major challenges, potential solutions and opportunities required to achieve and operate a circular plastics economy. This article is part of a discussion meeting issue 'Science to enable the circular economy'.

rayyan-671784051

Ethyl Lactate Production from the Catalytic Depolymerisation of Post-consumer Poly(lactic acid)

JOURNAL OF POLYMERS AND THE ENVIRONMENT

Roman-Ramirez, Luis A. and Powders, Mark and McKeown, Paul and Jones, Matthew D. and Wood, Joseph

ONE NEW YORK PLAZA, SUITE 4600, NEW YORK, NY, UNITED STATES

Bioplastics such as poly(lactic acid) (PLA), which are derived from renewable sources, promoted as biodegradable and implemented for numerous functions, offer a promising alternative to the enduring synthetic plastics abundant in society. However, the degradation of PLA is slow under natural environmental conditions. A chemical recycling route is thus required to couple mitigation of plastic persistence repercussions with circular economy adherence. In the present work, the production of ethyl lactate by the catalysed transesterification of post-consumer PLA was investigated. The catalyst employed was a propylendiamine Zn(II) complex. The PLA samples investigated consisted of a phone case, an infant's toy, a film, a cup and 3D printing material. Degradation reactions were studied at 50 degrees C and 90 degrees C and the concentrations measured at two different time intervals, 1 h and 3 h. The results revealed that greater activity of the catalyst was observed at 50 degrees C for two PLA samples (cup, 3D print). PLA film achieved the greatest lactate yield (71%) of all samples after 3 h at 50 degrees C. It is concluded that the propylenediamine Zn(II) catalyst can be used to produce green solvent ethyl lactate at mild temperatures from post-consumer PLA, even in the presence of unknown additives.

rayyan-671784063

Organocatalysis for versatile polymer degradation

GREEN CHEMISTRY

McKeown, Paul and Kamran, Muhammad and Davidson, Matthew G. and Jones, Matthew D. and Roman-Ramirez, Luis A. and Wood, Joseph

THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND

The use of a simple, cheap and effective organocatalyst, tetramethylammonium methyl carbonate, has been exploited for the transesterification of a range of commercial polymer samples. PLA, PCL, PC and PET have been successfully broken down into useful products, with the repolymerisation of DMT to PET demonstrated, highlighting a truly circular economy approach.

rayyan-671784067

From Trash to Cash: How Blockchain and Multi-Sensor-Driven Artificial Intelligence Can Transform Circular Economy of Plastic Waste?

ADMINISTRATIVE SCIENCES

Chidepatil, Aditya and Bindra, Prabhleen and Kulkarni, Devyani and Qazi, Mustafa and Kshirsagar, Meghana and Sankaran, Krishnaswamy

ST ALBAN-ANLAGE 66, CH-4052 BASEL, SWITZERLAND

Virgin polymers based on petrochemical feedstock are mainly preferred by most plastic goods manufacturers instead of recycled plastic feedstock. Major reason for this is the lack of reliable information about the quality, suitability, and availability of recycled plastics, which is partly due to lack of proper segregation techniques. In this paper, we present our ongoing efforts to segregate plastics based on its types and improve the reliability of information about recycled plastics using the first-of-its-kindblockchain smart contractspowered bymulti-sensor data-fusion algorithms using artificial intelligence. We have demonstrated how different data-fusion modes can be employed to retrieve various physico-chemical parameters of plastic waste for accurate segregation. We have discussed how these smart tools help in efficiently segregating commingled plastics and can be reliably used in the circular economy of plastic. Using these tools, segregators, recyclers, and manufacturers can reliably share data, plan the supply chain, execute purchase orders, and hence, finally increase the use of recycled plastic feedstock.

rayyan-671784072

Bottle house: utilising appreciative inquiry to develop a user acceptance model

BUILT ENVIRONMENT PROJECT AND ASSET MANAGEMENT

Adefila, Arinola and Abuzeinab, Amal and Whitehead, Timothy and Oyinlola, Muyiwa

HOWARD HOUSE, WAGON LANE, BINGLEY BD16 1WA, W YORKSHIRE, ENGLAND

Purpose - This paper develops a novel user-acceptance model for circular solutions to housing design. The model has been systematically developed from a case study of an upcycled plastic bottle building in a low-income community in Nigeria. It is common practice to use participatory approaches to consult end users in communities, typically after design concepts have been proposed and conceptualised. However, this often leads to critical socio-cultural or usability elements being overlooked and the design being substandard. Therefore, this paper develops a robust model for designers, specialists and activists involved in construction that can be used during all phases of a project. This approach demonstrates that user needs should be considered before building designs and plans are generated, providing a greater frame of reference for practitioners, consultants and end users. Enabling the integration of holistic needs of the community and the development of circular design solution. Design/methodology/approach - A case study methodology has been employed to develop this model, uses appreciative inquiry methodology. This includes multiple methods to capture end users' perception: focus groups, interactions with the local community and self-recorded comments. This case study is part of a broader research project to develop replicable low-cost self-sufficient homes utilising local capacity using upcycled, locally available materials. Findings - The findings identify the challenges associated with designing circular solution housing without a robust understanding of interrelated factors, which ensure sustainability and user acceptance. The conclusions demonstrate why essential socio-cultural factors, usually unrelated to technical development, should be understood and contextualised when designing sustainable solutions in low/middle-income communities. The authors argue that without this holistic approach, undesirable consequences may arise, often leading to more significant challenges. Instead of referring to multiple frameworks, this distinctive model can be used to evaluate user acceptance for low-cost housing in particular and other dimensions of circular solution design that involve end-user acceptance. The model blends circular solution dimensions with user-acceptance concerns offering a guide that considers essential features that are both user-friendly and pragmatic, such as utility, technological innovation and functionality as well as their intersectionality. Research limitations/implications - The research relied on a single case study, which focussed on end-user engagement of upcycling waste materials as an application of circular solutions. The model will contribute to developing socially accepted circular solutions taking into consideration local context factors. Originality/value - The paper is proposing a model for user acceptance of circular construction materials relevant to low- and middle-income countries (LMICs).

rayyan-671784075

Factors for eliminating plastic in packaging: The European FMCG experts' view

JOURNAL OF CLEANER PRODUCTION

Ma, Xuezi and Park, Curie and Moultrie, James

THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND

The fast-moving-consumer-goods (FMCG) sector is in the spotlight as a culprit for the current plastic waste problem. However, few studies provide insight into plastic elimination from the FMCG perspective. This qualitative study explores what the FMCG industry encounters when they attempt to address the plastic packaging issue. We conducted 13 semi-structured interviews with selected managers and technology experts in 7 European FMCGs. The analysis uses am original approach, named 'the Factor Mapping Grid', developed to stimulate responses from participants and map relationships between different factors. Results include 7 critical factors, and show that FMCG managers believe that pressure from "consumers" is the most prominent factor in reducing plastic. But, consumers are also equally viewed as a barrier to transition and thus act as a double-edged sword for FMCGs, depending on their awareness of plastic as an issue, and their willingness to take actions. All firms view legislation as an important enabler, but acknowledge that this is out of their control. It is evident that for industry, there is a general desire to reduce plastic, but there is a reluctance to be the first, and thus, a 'we will if you will' phenomenon is observed. Crown Copyright (C) 2020 Published by Elsevier Ltd. All rights reserved.

rayyan-671784086

Dioxomolybdenum complex as an efficient and cheap catalyst for the reductive depolymerization of plastic waste into value-added compounds and fuels

GREEN CHEMISTRY

Nunes, Beatriz F. S. and Conceicao Oliveira, M. and Fernandes, Ana C.

THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND

This work describes the efficient and selective reductive depolymerization of PET, PBT, PCL, PLA and PDO plastic waste into value-added compounds and fuels, including 1,6-hexanediol, xylene and propane, catalyzed by the eco-friendly, cheap and air-stable dioxomolybdenum complex MoO2Cl2(H2O)(2) using silanes as reducing agents. The catalyst MoO2Cl2(H2O)(2) can be used in at least 8 catalytic cycles in the reductive depolymerization of PCL with excellent activity and the catalytic system PMHS/MoO2Cl2(H2O)(2) was successfully applied in the production of propane from the reductive depolymerization of PLA on a gram scale. Moreover, this method was also efficiently applied in the selective reduction of a PCL, PLA and PET mixture.

rayyan-671784089

Hydrogenative Depolymerization of End-of-Life Poly(bisphenol A carbonate) with in situ Generated Ruthenium Catalysts

CHEMISTRYSELECT

Alberti, Christoph and Kessler, Jannik and Eckelt, Sarah and Hofmann, Melanie and Kindler, Tim-Oliver and Santangelo, Nicolo and Fedorenko, Elena and Enthaler, Stephan

POSTFACH 101161, 69451 WEINHEIM, GERMANY

One essential aspect to create a circular economy can be the valorisation of plastic waste to create valuable chemicals. The depolymerization, the converse reaction of the polymer built-up process, can be promising to reach the targets of a circular economy. Depolymerizations can provide monomers, which are polymerized in a subsequent process. We have explored the hydrogenative depolymerization of end-of-life poly(bisphenol A carbonate) (EoL-PBPAC). Applying an in situ generated catalyst derived from the precursors [RuClH(CO)(PPh3)(3)] and 2-(di-iso-propylphosphino)ethylamine EoL-PBPAC, e. g. a DVD, was reduced to methanol and bisphenol A in good to excellent yields. For closing the cycle bisphenol A may be reprocessed as monomer for the reproduction of new PBPAC. The second depolymerization product methanol may be submitted to the hydrogen economy for release of hydrogen and in consequence energy generation.

rayyan-671784099

Stocks and flows of polyvinyl chloride (PVC) in China: 1980-2050

RESOURCES CONSERVATION AND RECYCLING

Liu, Yijie and Zhou, Chuanbin and Li, Feng and Liu, Hongju and Yang, Jianxin

RADARWEG 29, 1043 NX AMSTERDAM, NETHERLANDS

Polyvinyl chloride (PVC) is a widely consumed plastic material and may lead various environmental pollutions. China produces and consumes the largest amount of PVC material in the world, owing to its rapid urbanization and economic growth. Herein, we establish a dynamic material flow analysis methodology for quantifying PVC stocks and flows in China, including material input, manufacturing and consumption distribution, and waste management stage. We examine the material flow of PVC in China from 1980 to 2015. The PVC trajectory analysis from 2016 to 2050 is based on the historical PVC material consumption data and scenario analysis. Total amount of PVC consumption in all types of products dramatically increased from 0.4 Mt (0.4 kg/capita) in 1980 to 14.5 Mt (10.7 kg/capita) in 2015, with a cumulative amount of 173.7 Mt. The rapid increase of PVC consumption in China significantly accelerated the PVC waste accumulation, reaching 66.3 Mt, accounting for 38.2% of total PVC use from 1980 to 2015. Building & construction sector has the largest PVC in-use stock, while consumer goods sector generated the largest PVC waste. In recent fifteen years, mechanical recycling, chemical recycling, incineration, and landfill of PVC waste ratios are 25.5%, 0.8%, 9.3%, and 36.0%, respectively. The PVC trajectory analysis shows that by the end of 2050, the accumulative PVC waste in China will be 508.6 Mt in the limited growth scenario and 562.0 Mt in the business as usual scenario. Based on the MFA results, policies for improving PVC recycling system were analyzed in this work.

rayyan-671784125

Rise of the sustainable circular economy platform from waste plastics: A biotechnological perspective

MRS ENERGY & SUSTAINABILITY

Bora, Debajeet K.

CAMPUS, 4 CRINAN ST, LONDON, N1 9XW, ENGLAND

The circular economy aspects of PET (polyethylene terephthalate) waste conversion into value-added products are discussed concerning different governmental policies and industrial protocol for plastic degradation.The use of microbial enzymes such as PET hydrolase is discussed regarding PET (polyethylene terephthalate) degradation.The primary purpose of this perspective is a critical analysis of the correlation of the current state-of-the-art rising circular economy platform enacted across the world with close looping of PET (polyethylene terephthalate)-based plastic polymer disposal and sustainable recycling and upcycling technology. The goal of the upcycling process is to get the low-cost value-added monomer than those obtained from the hydrocarbon industry from the sustainability prospect. A summary of the circular bio-economic opportunities has also been described. Next, how the PET hydrolase enzyme degrades the PET plastic is discussed. It is followed by an additional overview of the effect of the mutant enzyme for converting 90% of plastics into the terephthalate monomer. A site-directed mutagenesis procedure obtains this particular mutant enzyme. The diversity of different microbial organism for producing PET hydrolase enzyme is finally discussed with a suggested outlook of the circular economy goal from the viewpoint of plastic degradation objectives soon.

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Barriers and challenges to plastics valorisation in the context of a circular economy: Case studies from Italy

JOURNAL OF CLEANER PRODUCTION

Paletta, Angelo and Leal Filho, Walter and Balogun, Abdul-Lateef and Foschi, Eleonora and Bonoli, Alessandra

THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND

In 2017, over 320 million tons of polymers, excluding fibers, were manufactured across the globe. The excessive amounts of plastics produced today pose a threat to both man and nature. Urgent approaches towards reducing plastic consumption and increasing its recyclability are needed. This paper discusses the matter of accelerating the circularity of plastic-based material systems. It investigates a sample of plastics-converting companies in Emilia Romagna region (Italy), which stand out for radical innovations in business models, with the aim to catalyse changes in current manufacturing practices. The findings provide empirical support for a positive relationship between business strategies and the use of non-virgin plastic materials. The innovative value of this paper relies on the fact that it elaborates on the vision established within the European Strategy for Plastics in a Circular Economy that sets ambitious targets about achieving high plastic recycling targets by 2025. Legislative, economic, technological and social barriers can only be tackled by radically revising the current philosophy of designing, producing, distributing and consuming plastic as part of goods and services. A systemic thinking perspective is an essential building block in this context: moving from a micro to a meso-scale analysis can represent a useful means supporting the creation of viable management approaches towards achieving environmental and economic gains, especially in European plastic conversion industry, where SMEs are the majority (about 50000). Thanks to its analysis and scope, this paper provides useful insights to the plastic industry: it shows that this substantial improvements in this sector will require innovative solutions and major efforts by key decision makers, producers, recyclers, manufacturer, retailers as well as consumers. (C) 2019 Elsevier Ltd. All rights reserved.

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Open Source Waste Plastic Granulator

TECHNOLOGIES

Ravindran, Arvind and Scsavnicki, Sean and Nelson, Walker and Gorecki, Peter and Franz, Jacob and Oberloier, Shane and Meyer, Theresa K. and Barnard, Andrew R. and Pearce, Joshua M.

ST ALBAN-ANLAGE 66, CH-4052 BASEL, SWITZERLAND

In order to accelerate deployment of distributed recycling by providing low-cost feed stocks of granulated post-consumer waste plastic, this study analyzes an open source waste plastic granulator system. It is designed, built, and tested for its ability to convert post-consumer waste, 3D printed products and waste into polymer feedstock for recyclebots of fused particle/granule printers. The technical specifications of the device are quantified in terms of power consumption (380 to 404 W for PET and PLA, respectively) and particle size distribution. The open source device can be fabricated for less than $2000 USD in materials. The experimentally measured power use is only a minor contribution to the overall embodied energy of distributed recycling of waste plastic. The resultant plastic particle size distributions were found to be appropriate for use in both recyclebots and direct material extrusion 3D printers. Simple retrofits are shown to reduce sound levels during operation by 4dB-5dB for the vacuum. These results indicate that the open source waste plastic granulator is an appropriate technology for community, library, maker space, fab lab, or small business-based distributed recycling.

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Circular use of plastics-transformation of existing petrochemical clusters into thermochemical recycling plants with 100% plastics recovery

SUSTAINABLE MATERIALS AND TECHNOLOGIES

Thunman, Henrik and Vilches, Teresa Berdugo and Seemann, Martin and Maric, Jelena and Vela, Isabel Canete and Pissot, Sebastien and Nguyen, Huong N. T.

RADARWEG 29, 1043 NX AMSTERDAM, NETHERLANDS

Plastics represent a serious waste-handling problem, with only 10% of the plastic waste (PW) generated worldwide being recycled. The remainder follows a linear economy model, involving disposal or incineration. Thermochemical recycling provides an opportunity to dose the material cycle, and this work shows how this can be achieved using the existing petrochemical infrastructure. The transformation of a generic petrochemical cluster based on virgin fossil feedstocks into a cluster that is based on PW has the following proposed sequence: (1) the feedstock is partially replaced (45% on carbon basis) by PW

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An Innovative Route to Circular Rigid Plastics

SUSTAINABILITY

van Engelshoven, Yuri and Wen, Pingping and Bakker, Maarten and Balkenende, Ruud and Rem, Peter

ST ALBAN-ANLAGE 66, CH-4052 BASEL, SWITZERLAND

An innovative route for plastics recycling is proposed, based on a combination of a logarithmic sorting process and colour plus high-resolution near-infrared (NIR) sensors. Although counterintuitive, it is shown that such a technology could sort clean flakes from rigid packaging waste into a very large number of different plastic grades with modest sorter capacity, provided that the chosen sensor is able to differentiate correctly between any two grades of plastics in the waste. Tests with high-resolution NIR on single pixels of transparent flakes from different types and brands of packaging show that this is indeed the case for a selection of 20 different packaging items bought from shops. Moreover, the results seem to indicate, in line with previous research, that high-resolution NIR data can be linked to important physical plastic properties like the melt flow viscosity and tensile strength. The attraction of deep sorting of waste plastics with relatively cheap sensors and modest sorter capacity is that the present industrial practice of tuning plastic grades to specific applications could coexist with commercial high-grade recycling at high levels of circularity and low carbon footprint. Therefore, advanced recycling technology is likely to be a societal alternative to phasing out plastics for rigid applications.

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A circular economy approach to plastic waste

POLYMER DEGRADATION AND STABILITY

Payne, Jack and McKeown, Paul and Jones, Matthew D.

THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND

Growing environmental concerns associated with the accumulation of plastic waste in the natural environment has incentivised considerable research into renewable alternatives, and more recently, alternative waste management strategies. This review aims to introduce poly (lactic acid) (PLA), a bioplastic, and recent research within the field. Attention will then shift to research surrounding plastic waste management. Various end-of-life (EOL) options available to plastics will be discussed more broadly, before presenting existing technologies, challenges and future opportunities exclusively for PLA. Herein, all waste management strategies presented for PLA are discussed within the context of industrial feasibility. (C) 2019 Elsevier Ltd. All rights reserved.

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Chemical Recycling of Consumer-Grade Black Plastic into Electrically Conductive Carbon Nanotubes

C-JOURNAL OF CARBON RESEARCH

Hedayati, Ali and Barnett, Chris J. and Swan, Gemma and White, Alvin Orbaek

ST ALBAN-ANLAGE 66, CH-4052 BASEL, SWITZERLAND

The global plastics crisis has recently focused scientists' attention on finding technical solutions for the ever-increasing oversupply of plastic waste. Black plastic is one of the greatest contributors to landfill waste, because it cannot be sorted using industrial practices based on optical reflection. However, it can be readily upcycled into carbon nanotubes (CNTs) using a novel liquid injection reactor (LIR) chemical vapor deposition (CVD) method. In this work, CNTs were formed using black and white polystyrene plastics to demonstrate that off-the-shelf materials can be used as feedstock for growth of CNTs. Scanning electron microscopy analysis suggests the CNTs from plastic sources improve diameter distribution homogeneity, with slightly increased diameters compared with control samples. Slight improvements in quality, as determined by Raman spectroscopy of the D and G peaks, suggest that plastics could lead to increased quality of CNTs. A small device was constructed as a demonstrator model to increase impact and public engagement.

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High-fold improvement of assorted post-consumer poly(ethylene terephthalate) (PET) packages hydrolysis using Humicola insolens cutinase as a single biocatalyst

PROCESS BIOCHEMISTRY

de Castro, AM and Carniel, A and Stahelin, D and Chinelatto, LS and Honorato, HD and de Menezes, SMC and de Castro, Aline Machado and Carniel, Adriano and Stahelin, Diego and Chinelatto Junior, Luiz Silvino and Honorato, Hercilio de Angeli and Cabral de Menezes, Sonia Maria

THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND

The dissemination of technologies for poly(ethylene terephthalate) (PET) recycling is of paramount importance in the context of the plastics circular economy. One of the most promising alternatives is to use enzymes as catalysts for PET depolymerization to its monomers, but this route still needs improvement, especially regarding titer and productivity. In the present work, a sequential approach comprised of fractional factorial and central composite rotatable designs, the path of steepest ascent and one-way evaluation of variable effect, was performed to address these limitations, during assorted post-consumer PET (PC-PET) hydrolysis catalyzed by Humicola insolens cutinase. The highest terephthalic acid concentration and productivity during PC-PET hydrolysis were 100.9 mM (16.8 g/L) and 14.4 mM/day, corresponding to overall improvements of 10-fold and 20-fold, respectively. These data are among the best results described so far for enzyme-catalyzed hydrolysis of used PET packages. Also, the use of a single enzyme system, instead of multiple biocatalysts to achieve final conversion of PET to its monomers, lowers the process complexity and costs.

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Efficiency in the environmental management of plastic wastes at Brazilian ports based on data envelopment analysis

MARINE POLLUTION BULLETIN

Gobbi, Clarice Neffa and Lourenco Sanches, Vania Maria and de Oliveira Cavalcanti Guimaraes, Maria Jose and Vasconcelos de Freitas, Marcos Aurelio and Acordi Vasques Pacheco, Elen Beatriz

THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND

The aim of this study was to analyze different port areas (leased, nonleased and vessels) in terms of plastic segregation (scenario 1) and how much of this plastic is recycled (scenario 2). Data envelopment analysis was applied and the variables were total amount of solid waste and percentage of segregated plastic in relation to total solid waste (scenario 1) and amount of segregated plastics and percentage of recycled in relation to segregated plastics (scenario 2). Segregation efficiency was low (49%) in the nonleased area, but all the segregated material is recycled, suggesting that the management bottleneck in this case is waste segregation. Similar segregation results were obtained in the leased areas and vessels (36 and 35%, respectively), but recycling efficiency was greater in the former (92 and 24%, respectively).

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3Rs Policy and plastic waste management in Thailand

JOURNAL OF MATERIAL CYCLES AND WASTE MANAGEMENT

Wichai-utcha, N. and Chavalparit, O.

233 SPRING ST, NEW YORK, NY 10013 USA

Plastic has become an important and integral part of society throughout the world due to its various applications, such as packaging, agriculture, automobile parts, electronic applications and medical devices. The plastic fabrication process can be modified to form various shapes, colors and specifications according to customer needs. Consequently, the amount of plastic waste is increasing due to the increase in plastic consumption because of the increasing population. Moreover, the problem of marine plastic debris is on the rise globally, including in Thailand, which results from the irresponsibility of mankind. Generally, plastic waste in Thailand can be generated from industrial processes and households. These two waste sources have caused the rise in plastic waste, which has contributed to the problem of waste management in Thailand. Additionally, Thailand is one of the contributors to the leakage of plastic waste into the ocean, which results from inefficient waste management. To reduce the impacts of plastic waste, effective measures have to be applied, such as reducing, reusing and recycling (3Rs) or energy recovery from plastic wastes. To ensure the proper management of solid waste, Thailand has established the National 3R Strategy and the National Master Plan for Waste Management (2016-2021). Furthermore, Thailand also launched a Plastic Debris Management Plan 2017-2021, which comprises several approaches, such as promotion and introduction of eco-packaging design and eco-friendly plastic substitution, development of the material flow for plastic containers and packaging inventory, implementation of the 3Rs (reduce-reuse-recycle) strategy for plastic debris management, and the promotion of education for relevant stakeholders in the field of plastics and its alternative materials. In addition, the options to create more effective plastic waste management are to implement legislation or revise the laws to improve the efficiency and reduce the amount of plastic waste, such as imposing plastic bag fees, strengthening the 3Rs measures, and encouraging the implementation of a circular economy in plastic value chains.

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Towards a Circular Economy: A Case Study of Waste Conversion into Housing Units in Cotonou, Benin

URBAN SCIENCE

Allam, Zaheer and Jones, David Sydney

ST ALBAN-ANLAGE 66, CH-4052 BASEL, SWITZERLAND

Cotonou is the largest city and main economic centre of the nation of Benin, Africa. Following independence, the city has experienced major population growth resulting in the extensive development of slums on flood plains and marshes causing the loss of biodiversity of these fragile ecosystems. Infrastructural development, unable to keep pace with informal settlement development, and a cumbersome municipal service system, have led to the illegal dumping of organic and plastic wastes, and extensive land pollution. In addition, due to its primary dune coastal location, Cotonou is facing sea level rise risks demonstrating the urgent need to sustainably address urban development. Through a socio-technical framework, this paper considers the use of transformed plastic wastes as new settlement building blocks to reduce solid waste, create jobs, and develop low-cost housing. This new strategy offers employment empowerment and a strategy to generate an income of US$2,380,000 per annum and the creation of 3200 permanent jobs.

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Physico-chemical properties of excavated plastic from landfill mining and current recycling routes

WASTE MANAGEMENT

Canopoli, L. and Fidalgo, B. and Coulon, F. and Wagland, S. T.

THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND

In Europe over 5.25 billion tonnes of waste has been landfilled between 1995 and 2015. Among this large amount of waste, plastic represents typically 5-25 wt% which is significant and has the potential to be recycled and reintroduced into the circular economy. To date there is still however little information available of the opportunities and challenges in recovering plastics from landfill sites. In this review, the impacts of landfill chemistry on the degradation and/or contamination of excavated plastic waste are analysed. The feasibility of using excavated plastic waste as feedstock for upcycling to valuable chemicals or liquid fuels through thermochemical conversion is also critically discussed. The limited degradation that is experienced by many plastics in landfills (>20 years) which guarantee that large amount is still available is largely due to thermooxidative degradation and the anaerobic conditions. However, excavated plastic waste cannot be conventionally recycled due to high level of ash, impurities and heavy metals. Recent studies demonstrated that pyrolysis offers a cost effective alternative option to conventional recycling. The produced pyrolysis oil is expected to have similar characteristics to petroleum diesel oil. The production of valuable product from excavated plastic waste will also increase the feasibility of enhanced landfill mining projects. However, further studies are needed to investigate the uncertainties about the contamination level and degradation of excavated plastic waste and address their viability for being processed through pyrolysis. (C) 2018 Elsevier Ltd. All rights reserved.

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Chemical upcycling of waste polyolefinic plastics to low-carbon synthetic naphtha for closing the plastic use loop

Science of the Total Environment

Dai, L. and Zhou, N. and Lv, Y. and Cheng, Y. and Wang, Y. and Liu, Y. and Cobb, K. and Chen, P. and Lei, H. and Ruan, R.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85103991504&doi=10.1016%2fj.scitotenv.2021.146897&partnerID=40&md5=d5bce6c27f5ae41f16d47e0a7249198c

["Center for Biorefining and Department of Bioproducts and Biosystems Engineering, University of Minnesota, 1390 Eckles Ave., St. Paul, MN 55108, United States", "Engineering Research Center for Biomass Conversion, Nanchang University, Nanchang, Jiangxi 330047, China", "Biochemical Engineering College, Beijing Union University, No. 18, Fatouxili 3 Area, Chaoyang District, Beijing, 100023, China", "Department of Biological Systems Engineering, Washington State University, Richland, WA 99354, United States"]

Designing an effective pathway to remove waste plastics from landfill and incineration plants and create a circular economy requires a more appropriate technology beyond the conventional mechanical recycling by melting and re-molding. This study aims to convert waste plastic into low-carbon synthetic naphtha which can be used as a feedstock for new plastic production, via a new and simple technical approach. To be specific, waste plastics are decomposed and reformed into naphtha fractions via a one-step catalytic pyrolysis over Al2O3 pillared montmorillonite clay catalyst. Experimental results show that Al2O3 pillared montmorillonite clay produces up to 60.3% C5-C12 alkanes, while ZSM-5 gives high contents of aromatics (46%) and olefins (35%). The promising results of Al2O3 pillared M-clay may be due to the special features of this material, including the large pore size and Al2O3-induced active sites (more Brønsted acid sites). The further batch experiments confirm the feasibility of scaling up and processing the polyolefinic plastic mixture. © 2021 Elsevier B.V.

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Synergistic interactions during hydrothermal liquefaction of plastics and biomolecules

Chemical Engineering Journal

Seshasayee, M.S. and Savage, P.E.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85102615207&doi=10.1016%2fj.cej.2021.129268&partnerID=40&md5=e37f0c1fcfbc436840a118b18ab7a44f

Chemical Engineering Department, Pennsylvania State University, 121D CBE Building, University Park, PA 16802, United States

We performed co-liquefaction of plastics and biomolecules, in ratios that mimic their abundance in municipal solid waste (MSW), in both subcritical (300, 350 °C) and supercritical (400, 425 °C) water. Hydrothermal liquefaction (HTL) of this simulated MSW mixture produces an oil product, and the highest energy recovery (45%) in the oil occurred at the lowest temperature examined (300 °C). This energy recovery was more than twice that expected, based on energy recovery from HTL of each component individually at the same condition. Interactions between biomolecules and plastics increase the oil yield from HTL and enable the processing of plastics at lower HTL operating temperatures (e.g., 300 ˚C) than would be possible for processing the plastics alone. Cellulose, starch, and lignin interact synergistically with mixtures of polypropylene, polycarbonate, polystyrene and polyethylene terephthalate to increase the oil yield. These interactions form new products and accelerate the depolymerization of the plastics. © 2021 Elsevier B.V.

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Possibility of incorporating waste plastic film flakes into warm-mix asphalt as a bitumen extender

Construction and Building Materials

Almeida, A. and Capitão, S. and Estanqueiro, C. and Picado-Santosc, L.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85104989630&doi=10.1016%2fj.conbuildmat.2021.123384&partnerID=40&md5=9524bfcd5c72cb0486b68a79cec3e2be

["Universidade de Coimbra, Departamento de Engenharia Civil, Rua Luís Reis Santos, Coimbra, 3030-788, Portugal", "CITTA Centro de Investigação do Território, Transportes e Ambiente, Rua Dr. Roberto Frias, Porto, 4200-465, Portugal", "Instituto Politécnico de Coimbra, Instituto Superior de Engenharia de Coimbra, Departamento de Engenharia Civil, Rua Pedro Nunes, Coimbra, 3030-199, Portugal", "CERIS, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais 1, Lisboa, 1049-001, Portugal"]

A warm-mix asphalt (WMA) produced at 100 °C and incorporating waste plastic film flakes was evaluated. The investigation comprised two stages analysing the WMA and a conventional HMA with the same plastic material. The first stage established the WMA composition. The second stage comprised performance evaluation, for which the incorporation of plastic slightly increased stiffness, and fatigue resistance was similar for both mixtures. WMA with plastic was the worst in the uniaxial compression test and the best in the wheel-tracking test. The conclusion is that WMA incorporating waste plastic is a promising solution for low to intermediate traffic volume road infrastructures. © 2021 Elsevier Ltd

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Comprehensive evaluation of plastic flows and stocks in South Africa

Resources, Conservation and Recycling

Olatayo, K.I. and Mativenga, P.T. and Marnewick, A.L.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85103422888&doi=10.1016%2fj.resconrec.2021.105567&partnerID=40&md5=0f4613186fa4e730efe8aa394a56534b

["Postgraduate School of Engineering Management, Faculty of Engineering and the Built Environment, University of Johannesburg, South Africa", "Department of Mechanical, Aerospace and Civil Engineering, School of Engineering, The University of Manchester, Manchcester, M13 9PL, United Kingdom"]

There is an urgent need to tackle the major challenge of plastic waste, as the increase in production and consumption of plastics is generating higher levels of waste. The South African government formulated a Waste Research Development and Innovation (RDI) Roadmap to facilitate the transition to a circular economy. To support this roadmap, this paper defines the plastic material flows within the country to enable the benchmarking of plastic footprints and to inform the transition to a circular economy. The flows and stocks of plastic were quantified using material flow analysis for a reference year with the most complete and recent data available. The paper presents the first known case of a Sankey diagram for plastic materials in South Africa and pioneers an approach to embed data uncertainty in a Sankey diagram and resource flows. The flow results for 2017 show an estimated 1,350,000 tons of primary plastic (24 kg/capita) and 2,742,970 tons of plastic product (49 kg/capita) were produced in South Africa, about 1,805,780 tons of primary plastic (32 kg/capita) were consumed and 2,247,323 tons (40 kg/capita) of plastic waste were generated. Furthermore, the study identified data and information gaps and underlying assumptions on waste evaluation that need to be revisited, and also proposes a new approach for a comprehensive evaluation of the recycling rate in South Africa. © 2021 Elsevier B.V.

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Techno-economic assessment of mechanical recycling of challenging post-consumer plastic packaging waste

Resources, Conservation and Recycling

Larrain, M. and Van Passel, S. and Thomassen, G. and Van Gorp, B. and Nhu, T.T. and Huysveld, S. and Van Geem, K.M. and De Meester, S. and Billen, P.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85104337640&doi=10.1016%2fj.resconrec.2021.105607&partnerID=40&md5=69fccf18a19e55460e3076422be4b2e6

["University of Antwerp, Faculty of Applied Engineering, iPRACS, Groenenborgerlaan 171, Antwerpen, 2020, Belgium", "University of Antwerp, Faculty of Business and Economics, Department of Engineering Management, Prinsstraat 13, Antwerpen, 2000, Belgium", "University of Antwerp, Faculty of Business and Economics, Department of Engineering Management, Prinsstraat 13, 2000 Antwerpen, Belgium", "Ghent University, Faculty of Bioscience Engineering, STEN, Coupure Links 653, Gent, B9000, Belgium", "Eco-oh! Recycling, Europark 1075, Houthalen, 3530, Belgium", "Ghent University, Faculty of Engineering and Architecture, LCT, Technologiepark 125, Zwijnaarde, 9052, Belgium", "Ghent University, Faculty of Bioscience Engineering, LCPE, Graaf Karel de Goedelaan 5, Kortrijk, 8500, Belgium"]

Increasing plastic recycling rates is crucial to tackle plastic pollution and reduce consumption of fossil resources. Recycling routes for post-consumer plastic fractions that are technologically and economically feasible remain a challenge. Profitable value chains for recycling mixed film and tray-like plastics have hardly been implemented today, in sharp contrast to recycling of relatively pure fractions such as polyethylene terephthalate and high-density polyethylene bottles. This study examines the economic feasibility of implementing mechanical recycling for plastic waste such as polypropylene, polystyrene, polyethylene films and mixed polyolefins. In most European countries these plastic fractions are usually incinerated or landfilled whilst in fact technologies exist to mechanically recycle them into regranulates or regrinds. Results show that the economic incentives for the recycling of plastic packaging depend predominantly on the product price and product yield. At current price levels, the most profitable plastic fraction to be recycled is PS rigids, with an internal rate of return of 14%, whereas the least profitable feed is a mixed polyolefin fraction with a negative internal rate of return in a scenario with steadily rising oil prices. Moreover, these values would be substantially reduced if oil prices, and therefore plastic product prices decrease. Considering a discount rate of 15% for a 15-year period, mechanical recycling is not profitable if no policy changes would be imposed by governments. Clearly low oil prices may jeopardize the mechanical recycling industry, inducing the need for policies that would increase the demand of recycled products such as imposing minimal recycled content targets. © 2021 Elsevier B.V.

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Matrix Trays: From waste to opportunities

Journal of Cleaner Production

Ali, A.K. and Layton, A. and Kio, P. and Williams, J.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85103760662&doi=10.1016%2fj.jclepro.2021.126813&partnerID=40&md5=ba434d1b24fc88e87b6ed56714853a62

Texas A&M University, College Station, TX 77845, United States

Matrix Trays are single-use plastic carriers used to transport integrated chips and circuit board components during automated test and assembly processes for Printed Circuit Boards. These trays represent a significant yet consistent waste stream

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Cradle-to-grave life cycle assessment of single-use cups made from PLA, PP and PET

Resources, Conservation and Recycling

Moretti, C. and Hamelin, L. and Jakobsen, L.G. and Junginger, M.H. and Steingrimsdottir, M.M. and Høibye, L. and Shen, L.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85101394063&doi=10.1016%2fj.resconrec.2021.105508&partnerID=40&md5=33be767372c07dfce84ed3f39122a139

["Utrecht University, Copernicus Institute of Sustainable Development, Utrecht, Netherlands", "Toulouse Biotechnology Institute (TBI), Federal University of Toulouse, Toulouse, France", "COWI A/S, Department of Waste and Contaminated Sites, Lyngby, Denmark", "COWI A/S, Department of Environment, Health and Safety, Lyngby, Denmark"]

Polylactide (PLA) is both bio�based and biodegradable and has therefore attracted increased attention for single-use plastics applications. Under the context of the recent EU Plastics and Bioeconomy strategies, this study uses life cycle assessment (LCA) to assess the environmental footprint of single-use drinking cups made from PLA, including 13 environmental impact categories. Land use changes (LUCs) were assessed based on a deterministic model. The manufacturing phase was modeled based on primary production data stemming directly from the industry. The end-of-life (EoL) impacts were assessed using the EASETECH. PLA cups were then compared with their petrochemical counterparts polyethylene terephthalate (PET) and polypropylene (PP) cups. Based on the available data quality of the petrochemical polymers, six impact categories were compared. For PLA cups, the process energy use in the conversion from biomass to PLA polymer was identified as the main environmental hotspot, followed by the electricity consumption of thermoforming of the cups. It was found that the biomass acquisition phase has a limited overall impact. LUCs contribute to a negligible impact in all impact categories except for climate change and photochemical ozone formation. Compared to PET cups, the current PLA cups offer environmental impact savings for climate change even including the impacts of LUC. Compared to both PET and PP cups, PLA cups offer savings for fossil fuels resource use but lead to higher impacts for photochemical ozone formation, acidification and terrestrial eutrophication. © 2021

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Post-consumer plastic packaging waste flow analysis for Brazil: The challenges moving towards a circular economy

Waste Management

Pimentel Pincelli, I. and Borges de Castilhos Júnior, A. and Seleme Matias, M. and Wanda Rutkowski, E.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85104732442&doi=10.1016%2fj.wasman.2021.04.005&partnerID=40&md5=9e86791d7619e8ec134b217feb1f80e3

["Department of Sanitation and Environmental Engineering, Federal University of Santa Catarina (Universidade Federal de Santa Catarina), Florianópolis, Brazil", "FLUXUS lab [INFRA/FEC], State University of Campinas (Unicamp), Campinas, Brazil"]

Plastic packaging has been used increasingly worldwide in a broad range of application. Plastic packaging has a short lifetime, which generates a large amount of waste. However, robust information on plastic packaging waste flow is generally not available, especially for developing countries such as Brazil. We analyzed and quantified Brazilian post-consumer plastic packaging waste (PPW) flows using material flow analysis (MFA) for the year 2017. The system modeled covered from the manufacturing stage of plastic packaging up to its waste management stage. We used a range of data sources, whose quality we assessed using uncertainty characterization. The results showed that Brazil generated 12 Mt of PPW in 2017, and the management of 63% of that was not monitored. The majority of monitored PPW was disposed of into landfills, but 0.8 Mt of PPW was improperly disposed. Informal collection was 24% greater than formally managed selective collection. Only 4.5% of the PPW generated in Brazil was recycled. The results identified the major national challenges in relation to PPW management as being that information systems needed to be improved, informal waste collectors needed to be socially and productively included in the management systems, and recovery systems needed to be developed towards a circular economy. © 2021

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Recycling of post-consumer plastic packaging waste in EU: Process efficiencies, material flows, and barriers

Waste Management

Antonopoulos, I. and Faraca, G. and Tonini, D.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85104335508&doi=10.1016%2fj.wasman.2021.04.002&partnerID=40&md5=cc1a9ffadf8cf8719db3bb26c4cd05d4

European Commission Joint Research Centre, Calle Inca Garcilaso 3, Sevilla, 41092, Spain

Increasing plastic waste recycling is a milestone of European environmental policy to reduce environmental impacts and dependency on foreign resources. This is particularly challenging for plastic packaging waste, consisting of very heterogeneous fractions and typically rather contaminated. In this study, we collected primary data from plants sorting and reprocessing plastic packaging waste to illustrate process efficiencies, material flows, and barriers. We observed that significant losses of target materials occurred both at sorting and reprocessing stages. These were higher for polymers such as films, polypropylene and polystyrene, and lower for polyethylene terephthalate and high-density polyethylene. Applying material flow analysis, we estimated an overall recycling rate for post-consumer plastic packaging waste in EU27 in 2017 of 14% (not considering waste exported as recycled

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PET waste as organic linker source for the sustainable preparation of MOF-derived methane dry reforming catalysts

Materials Advances

Karam, L. and Miglio, A. and Specchia, S. and El Hassan, N. and Massiani, P. and Reboul, J.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85104971832&doi=10.1039%2fd0ma00984a&partnerID=40&md5=cb3fb325ddd4d64e84cf183f060a2a04

["Department of Chemical Engineering, Faculty of Engineering, University of Balamand, P.O. Box 33, Amioun, El Koura, Lebanon", "Sorbonne Université, Campus UPMC, CNRS UMR-7197, Laboratoire de Réactivité de Surface, 4 Place Jussieu, Paris, 75005, France", "Politecnico di Torino, Department of Applied Science and Technology, Corso Duca degli Abruzzi 24, Torino, 10129, Italy"]

A catalyst made of Ni0 nanoparticles highly dispersed on a lamellar alumina support was prepared by an environmentally-friendly route. The latter involved the synthesis of an aluminum-containing metal-organic framework (MOF) MIL-53(Al) in which the linkers were derived from the depolymerization of polyethylene terephthalate (PET) originating from plastic wastes. After demonstrating the purity and structure integrity of the PET-derived MIL-53(Al), this MOF was impregnated with nickel nitrate salt and then calcined to form a lamellar Ni-Al2O3 mixed metal oxide with a high surface area (SBET = 1276 m2 g-1, N2 sorption). This mixed oxide consisted of nickel aluminate nanodomains dispersed within amorphous alumina, as revealed by PXRD and TPR analyses. Subsequent reduction under H2 resulted in the formation of well-dispersed 5 nm Ni0 nanoparticles homogeneously occluded within the interlamellar porosity of the γ-alumina matrix, as attested by electron microscopy. This waste-derived catalyst displayed catalytic performances in the reaction of dry reforming of methane (DRM) as good as its counterpart made from a MOF obtained from commercial benzene-1,4-dicarboxylic acid (BDC). Thus, under similar steady state conditions, at 650 °C and 1 bar, the PET-derived catalyst led to CH4 and CO2 conversions as high as those on the BDC-derived catalyst, and its catalytic stability and selectivity towards DRM were excellent as well (no loss of activity after 13 h and H2 : CO products ratio remaining at 1). Moreover, both catalysts were much better than those of a reference nickel alumina catalyst prepared by conventional impregnation route. This work therefore demonstrates the possibility of using plastic wastes instead of commercial chemicals to prepare efficient porous nickel-alumina DRM catalysts from MOFs, fostering the concept of circular economy. © The Royal Society of Chemistry.

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Recycling and utilization of polymers for road construction projects: An application of the circular economy concept

Polymers

Anwar, M.K. and Shah, S.A.R. and Alhazmi, H.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85105098352&doi=10.3390%2fpolym13081330&partnerID=40&md5=ebb08c0a04398a77bbf245815740d3cd

["Department of Civil Engineering, Pakistan Institute of Engineering and Technology, Multan, 66000, Pakistan", "National Center for Environmental Technology (NCET), Life Science and Environment Research Institute (LSERI), King Abdulaziz City for Science and Technology (KACST), Riyadh, 11442, Saudi Arabia"]

Numerous environmental issues arise as a result of a linear economy strategy: reserves become scarce and end up in landfills and as greenhouse gases. Utilizing waste as a resource or shifting towards a circular economy are among the effective strategies for addressing these issues. To track this shift, appropriate measures that concentrate on sustainable development while taking practical contexts into consideration are required. In this paper, we utilize plastic wastes as a replacement for bitumen for reuse aiming at a circular economy. The use of plastic waste materials, i.e., plastic bottles (PET) and gas pipes (PE) in asphalt materials as a bitumen modifier was studied through series of experimental lab test methods. Marshall samples were prepared using a conventional Marshall method containing five different percentages (0%, 5%, 10%, 15%, and 20%) of plastic content by total weight of bitumen. Samples were tested after 1 and 30 days and the result shows that the stability of plastic-modified asphalt concrete was increased after 30 days, while still meeting standard criteria with plastic contents up to 20%. Moreover, the addition of waste plastic in road construction is a very effective strategy for reusing plastic waste, which also provides economic and social benefits for a sustainable approach to road pavements. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

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United States plastics: Large flows, short lifetimes, and negligible recycling

Resources, Conservation and Recycling

Di, J. and Reck, B.K. and Miatto, A. and Graedel, T.E.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85099821789&doi=10.1016%2fj.resconrec.2021.105440&partnerID=40&md5=31bbf873742f6488a46b439493e07080

["School of Environment and Natural Resources, Renmin University of China, Beijing, 100872, China", "Center for Industrial Ecology, School of the Environment, Yale University, New Haven, CT 06511, United States"]

Given increasing concerns for the marine environment and human health, as well as trade restrictions from Asian countries, plastics have become a great challenge for the United States. This study addresses the seven commonly used plastics: low-density polyethylene/linear low-density polyethylene, high-density polyethylene, polyethylene terephthalate (PET), polypropylene, polystyrene, polyvinyl chloride, and other plastics. Material flows of the seven polymers were tracked from production into fabrication, manufacturing, flow into use, waste management, and recycling in the United States in 2015. Low- and high-density polyethylene and polypropylene were found to be the largest in both production and product manufacture. More than 88% of the plastics went into three end-use sectors: Packaging, Consumer and Institutional Products, and Building and Construction. In-use lifetimes across the plastics are generally short. Virgin plastics were mainly exported, while intermediate plastic products were largely imported. The actual end-of-life recycling rate of the plastics as a group was no more than 6.2%, with PET and the polyethylene family the most recycled. The high yearly plastic throughput and low recycling rate pose a serious challenge to the sustainability goals of the United States and is in stark contrast to the vision of a circular economy of plastics. © 2021

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Design for circularity guidelines for the EEE sector

Sustainability (Switzerland)

Berwald, A. and Dimitrova, G. and Feenstra, T. and Onnekink, J. and Peters, H. and Vyncke, G. and Ragaert, K.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85104025852&doi=10.3390%2fsu13073923&partnerID=40&md5=d8498018a013308fdc273ac083f65f2c

["Environmental & Reliability Engineering, Fraunhofer Institute for Reliability and Microintegration IZM, Berlin, 13355, Germany", "Pezy Group Groningen, Groningen, 9723 TV, Netherlands", "Center for Polymer & Material Technologies, Department of Materials, Textiles and Chemical Engineering, Faculty of Engineering & Architecture, Ghent University, Zwijnaarde, B-9052, Belgium"]

The increased diversity and complexity of plastics used in modern devices, such as electrical and electronic equipment (EEE), can have negative impacts on their recyclability. Today, the main economic driver for waste electrical and electronic equipment (WEEE) recycling stems from metal recovery. WEEE plastics recycling, on the other hand, still represents a major challenge. Strategies like design ‘for’, but also the much younger concept of design ‘from’ recycling play a key role in closing the material loops within a circular economy. While these strategies are usually analysed separately, this brief report harmonises them in comprehensive Design for Circularity guidelines, established in a multi-stakeholder collaboration with industry leaders from the entire WEEE value chain. The guidelines were developed at the product and part levels. They are divided in five categories: (1) avoidance of hazardous substances

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Learnings about design from recycling by using post-consumer polypropylene as a core layer in a co-injection molded sandwich structure product

Materials and Design

Gall, M. and Steinbichler, G. and Lang, R.W.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85101375188&doi=10.1016%2fj.matdes.2021.109576&partnerID=40&md5=6738285ae9fb6d37f0be067387f60c88

["Institute of Polymeric Materials and Testing, Johannes Kepler University Linz, Altenberger Straße 69, Linz, 4040, Austria", "Institute of Polymer Injection Moulding and Process Automation, Johannes Kepler University Linz, Altenberger Straße 69, Linz, 4040, Austria"]

In pursuit of a circular economy of plastics, there is a need to use more recycled plastics for new products. Polypropylene (PP) constitutes a major fraction of post-consumer plastic wastes, and mechanical recycling is currently the most sustainable recovery strategy. Sandwich-structured multi-layer products with recyclate cores are a seemingly easy way to satisfy demands for recyclate utilization without compromising on product aesthetics. We present the case of a reusable plastic transport box with a recycled content of 45 wt% manufactured by a co-injection molding process. The box was characterized by spectroscopic and thermo-analytical methods. Mechanical performance was tested on both specimen and product levels. A comparison was made to transport boxes fabricated entirely from virgin or entirely from recycled PP, respectively. A number of contaminants including foreign polymers were identified within the recyclate core layer of the sandwich-structured material. While these contaminants had no deteriorative effect on stiffness-controlled performance, a strong influence on strength-controlled and impact-related properties was observed. We argue that the presence of inclusions of both polymeric and inorganic nature is an intrinsic quality characteristic of post-consumer recyclates. These need to be considered in any design-from-recycling philosophy to guarantee functionality, reliability, and safety of products with recycled content. © 2021 The Authors

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Energy Potential of Plastic Waste Valorization: A Short Comparative Assessment of Pyrolysis versus Gasification

Energy and Fuels

Antelava, A. and Jablonska, N. and Constantinou, A. and Manos, G. and Salaudeen, S.A. and Dutta, A. and Al-Salem, S.M.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85101316502&doi=10.1021%2facs.energyfuels.0c04017&partnerID=40&md5=7bb02e8b836f0e6ca8e59fbcf39b80be

["Division of Chemical and Petroleum Engineering, School of Engineering, London South Bank University, London, SE1 0AA, United Kingdom", "Department of Chemical Engineering, University College London (UCL), London, WCIE 7JE, United Kingdom", "Department of Chemical Engineering, Cyprus University of Technology, 57 Corner of Athinon and Anexartisias, Limassol, 3036, Cyprus", "Mechanical Engineering Program, School of Engineering, University of Guelph, Guelph, Ontario N1G 2W1, Canada", "Environment and Life Sciences Research Centre, Kuwait Institute for Scientific Research (KISR), P.O. Box 24885, Safat, 13109, Kuwait"]

Plastics are abundant and have a high energy content making their use in energy applications attractive. This article presents a review on plastic waste (PW) management by pyrolysis and gasification, which are two types of thermochemical conversion (TCC) techniques. The conversion of PW and the application of its converted products are important steps toward reducing reliance on fossil fuels, enhancing closed-loop recycling of materials and the circular economy. The review presented herein also focuses on product distribution and yields with emphasis on the energy content and potential integration to energy systems and grids. It is found that pyro-oils have properties similar to conventional fuels such as diesel and can partially substitute for fossil fuels. In fact, the energy content of PW pyro-oils obtained by various researchers range from 41.10-46.16 MJ kg-1, which is close to the heating values of conventional fuels and thus are potential candidates for fuel applications. Typical treatment post-conversion is also conducted to maintain the quality of the oil produced and the removal of sulfur content to conform with market standards. On the other hand, syngas produced during gasification possesses a lower potential for fuel applications as its energy content may reach values as low as 20 MJ kg-1 in comparison to pyro-oil. However, depending on the process conditions, it is possible to increase the energy content to values of over 40 MJ kg-1. Additionally, syngas is the building block for many valuable chemicals. With appropriate treatment, the syngas obtained from the gasification of PW can be used in gas engines and can be converted to commercial products such as liquid fuels via the Fischer-Tropsch synthesis. This review also highlights some available commercial-scale plants for the TCC of PW and real-life application of their obtained products. It is noted that the integration of the processes to energy systems is technically and economically feasible. Real-life applications of products obtained from the pyrolysis and gasification of PW in different parts of the world are also discussed. The produced fuels have been used in cooking stoves and burned in a gas turbine, internal combustion engine, and direct injection diesel engine. ©

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Towards the Circular Economy: Converting Aromatic Plastic Waste Back to Arenes over a Ru/Nb2O5 Catalyst

Angewandte Chemie - International Edition

Jing, Y. and Wang, Y. and Furukawa, S. and Xia, J. and Sun, C. and Hülsey, M.J. and Wang, H. and Guo, Y. and Liu, X. and Yan, N.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85100180386&doi=10.1002%2fanie.202011063&partnerID=40&md5=02d50399011aadba29a487ade43470f4

["Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering, Feringa Nobel Prize Scientist Joint Research Center, Research Institute of Industrial Catalysis, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Shanghai, 200237, China", "Department of Chemical & Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore, 117585, Singapore", "Institute for Catalysis, Hokkaido University, N-21, W-10, Sapporo, 001-0021, Japan", "Elements Strategy Initiative for Catalysis and Battery, Kyoto University, Kyoto Daigaku Katsura, Nishikyo-ku, Kyoto, 615-8510, Japan"]

The upgrading of plastic waste is one of the grand challenges for the 21st century owing to its disruptive impact on the environment. Here, we show the first example of the upgrading of various aromatic plastic wastes with C−O and/or C−C linkages to arenes (75–85 % yield) via catalytic hydrogenolysis over a Ru/Nb2O5 catalyst. This catalyst not only allows the selective conversion of single-component aromatic plastic, and more importantly, enables the simultaneous conversion of a mixture of aromatic plastic to arenes. The excellent performance is attributed to unique features including: (1) the small sized Ru clusters on Nb2O5, which prevent the adsorption of aromatic ring and its hydrogenation

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Concepts and Sustainability Assessment of the Circular Carbon Economy: Chemical Recycling for Olefin Production

Chemie-Ingenieur-Technik

Seidl, L.G. and Poganietz, W.-R. and Keller, F. and Lee, R.P. and Grunwald, A. and Meyer, B.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85098129054&doi=10.1002%2fcite.202000102&partnerID=40&md5=9644ee34606379633ce89b484b0fcb38

["TU Bergakademie Freiberg, Institut für Energieverfahrenstechnik und Chemieingenieurwesen (IEC), Fuchsmühlenweg 9, Freiberg, 09599, Germany", "Karlsruher Institut für Technologie, Institut für Technikfolgenabschätzung und Systemanalyse (KIT-ITAS), Karlstraße 11, Karlsruhe, 76133, Germany", "Fraunhofer-Institut für Mikrostruktur von Werkstoffen und Systemen IMWS, Außenstelle Kohlenstoff-Kreislauf-Technologien (KKT), Fuchsmühlenweg 9, Freiberg, 09599, Germany"]

The transformation of the current linear carbon economy to a circular carbon economy with chemical recycling of plastic waste and recirculation of domestic carbon resources is investigated using the example of petroleum-based olefin production. The scenario-based sustainability assessment shows the potential of chemical recycling to cover olefin production in Germany. With perspective 2050, the entire olefin production could be realized by coupling green e-hydrogen with previously incinerated non-fossil waste. © 2021, Wiley-VCH Verlag. All rights reserved.

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Issues and challenges confronting the achievement of zero plasticwaste in Victoria, Australia

Recycling

Ng, A.W.M. and Ly, S. and Muttil, N. and Nguyen, C.N.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85101557166&doi=10.3390%2frecycling6010009&partnerID=40&md5=5103d896967bad7fb302d946f260e9f2

["College of Engineering and Science, Victoria University, Melbourne, VIC 8001, Australia", "Institute for Sustainable Industries & Livable Cities, Victoria University, P.O. Box 14428, Melbourne, VIC 8001, Australia"]

Despite the increase in popularity of the zero waste (ZW) concept, the successful implementation of this concept in waste management is still facing many challenges. The plastic recycling rate in Australia is at only about 9.4% (in 2017-2018). The state of Victoria (in Australia) has proposed an ambitious 10-year plan to upgrade its waste and recycling system and to divert about 80% of waste from landfills by 2030. The aim of this research is to study this currently proposed waste management plan and to develop a simulation model to assess the feasibility of achieving 80% diversion rate by 2030. The feasibility of achieving zero plastic waste by 2035 has also been assessed. In this direction, the existing knowledge of global ZW implementation has been reviewed to gain understanding of the challenges, obstacles, and uncertainties in achieving the ZW target. A simulation model is established using a method called double baselines. This method was developed to address the limitation of data availability for the model development. The model was run in 4 scenarios including one for Victoria’s current 10-year plan. Outcomes from the model are produced using six key considerations, including the rate of plastic consumption, waste to landfill, diversion rate, recycling rate, relative accumulative effort, and cost. The findings of this study point out that Victoria’s current plan for achieving an 80% diversion rate by 2030 is possible. On the other hand, the study results also suggest that achieving zero plastic waste by 2035 is less likely to happen. Hence, opportunities for improvement especially towards achieving the zero plastic waste are also presented. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

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An overview of plasticwaste generation and management in food packaging industries

Recycling

Ncube, L.K. and Ude, A.U. and Ogunmuyiwa, E.N. and Zulkifli, R. and Beas, I.N.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85101583326&doi=10.3390%2frecycling6010012&partnerID=40&md5=1e41715bbdce0f74a0e9708b7694c314

["Department of Mechanical, Energy and Industrial Engineering, Faculty of Engineering and Technology (FET), Botswana International University of Science and Technology (BIUST), Private Mail Bag 16, Palapye, Botswana", "Department of Chemical, Materials & Metallurgical Engineering Academic, FET, BIUST, Private Mail Bag 16, Palapye, Botswana", "Department of Mechanical and Materials Engineering, Faculty of Engineering and Built Environment, The National University of Malaysia, UKM, Bangi, 43600, Malaysia", "Botswana Institute for Technology Research and Innovation (BITRI), Private Bag 0082, Gaborone, Botswana"]

Over the years, the world was not paying strict attention to the impact of rapid growth in plastic use. This has led to unprecedented amounts of mixed types of plastic waste entering the environment unmanaged. Packaging plastics account for half of the global total plastic waste. This paper seeks to give an overview of the use, disposal, and regulation of food packaging plastics. Demand for food packaging is on the rise as a result of increasing global demand for food due to population growth. Most of the food packaging are used on-the-go and are single use plastics that are disposed of within a short space of time. The bulk of this plastic waste has found its way into the environment contaminating land, water and the food chain. The food industry is encouraged to reduce, reuse and recycle packaging materials. A wholistic approach to waste management will need to involve all stakeholders working to achieve a circular economy. A robust approach to prevent pollution today rather than handling the waste in the future should be adopted especially in Africa where there is high population growth. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

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Thermophilic whole-cell degradation of polyethylene terephthalate using engineered Clostridium thermocellum

Microbial Biotechnology

Yan, F. and Wei, R. and Cui, Q. and Bornscheuer, U.T. and Liu, Y.-J.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85084208285&doi=10.1111%2f1751-7915.13580&partnerID=40&md5=39b0c92e81001440321bc27b0d95a8fd

["CAS Key Laboratory of Biofuels, Shandong Provincial Key Laboratory of Synthetic Biology, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, China", "Dalian National Laboratory for Clean Energy, Qingdao, 266101, China", "University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, 100049, China", "Department of Biotechnology and Enzyme Catalysis, Institute of Biochemistry, Greifswald University, Felix-Hausdorff-Str. 4, Greifswald, D-17487, Germany"]

Polyethylene terephthalate (PET) is a mass-produced synthetic polyester contributing remarkably to the accumulation of solid plastics waste and plastics pollution in the natural environments. Recently, bioremediation of plastics waste using engineered enzymes has emerged as an eco-friendly alternative approach for the future plastic circular economy. Here we genetically engineered a thermophilic anaerobic bacterium, Clostridium thermocellum, to enable the secretory expression of a thermophilic cutinase (LCC), which was originally isolated from a plant compost metagenome and can degrade PET at up to 70°C. This engineered whole-cell biocatalyst allowed a simultaneous high-level expression of LCC and conspicuous degradation of commercial PET films at 60°C. After 14 days incubation of a batch culture, more than 60% of the initial mass of a PET film (approximately 50 mg) was converted into soluble monomer feedstocks, indicating a markedly higher degradation performance than previously reported whole-cell-based PET biodegradation systems using mesophilic bacteria or microalgae. Our findings provide clear evidence that, compared to mesophilic species, thermophilic microbes are a more promising synthetic microbial chassis for developing future biodegradation processes of PET waste. © 2020 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

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Impact of grinding of printed circuit boards on the efficiency of metal recovery by means of electrostatic separation

Suponik, T. and Franke, D.M. and Nuckowski, P.M. and Matusiak, P. and Kowol, D. and Tora, B.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85102111698&doi=10.3390%2fmin11030281&partnerID=40&md5=0cb1220f9878a4ad055ab99b276a7c8e

["Institute of Mining, Faculty of Mining, Safety Engineering and Industrial Automation, Silesian University of Technology, 2 Akademicka Street, Gliwice, 44�100, Poland", "Materials Research Laboratory, Faculty of Mechanical Engineering, Silesian University of Technology, 18A Konarskiego Street, Gliwice, 44�100, Poland", "KOMAG Institute of Mining Technology, 37 Pszczynska, Gliwice, 44�101, Poland", "Faculty of Mining and Geoengineering, AGH University of Science and Technology, 30 Mickiewicza, Kraków, 30�059, Poland"]

This paper analyses the impact of the method of grinding printed circuit boards (PCBs) in a knife mill on the efficiency and purity of products obtained during electrostatic separation. The separated metals and plastics and ceramics can be used as secondary raw materials. This is in line with the principle of circular economy. Three different screen perforations were used in the mill to obtain different sizes of ground grains. Moreover, the effect of cooling the feed to cryogenic temperature on the final products of separation was investigated. The level of contamination of the con-centrate, intermediate, and waste obtained as a result of the application of fixed, determined electrostatic separation parameters was assessed using ICP�AES, SEM–EDS, XRD, and microscopic analysis as well as specific density. The yields of grain classes obtained from grinding in a knife mill were tested through sieve analysis and by using a particle size analyser. The test results indicate that using a knife mill with a 1 mm screen perforation along with cooling the feed to cryogenic temperature significantly improves the efficiency of the process. The grinding products were char-acterised by the highest release level of the useful substance—metals in the free state. The purity of the concentrate and waste obtained from electrostatic separation was satisfactory, and the content of the intermediate, in which conglomerates of solid metal–plastic connections were present, was very low. The yield of concentrate and waste amounted to 26.2% and 71.0%, respectively. Their purity, reflected in the content of the identified metals (valuable metals), was at the level of 93.3% and 0.5%, respectively. In order to achieve effective recovery of metals from PCBs by means of electrostatic separation, one should strive to obtain a feed composed of grains <1000 μm and, optimally, <800 μm. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

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Closed-loop recycling of polyethylene-like materials

Häußler, M. and Eck, M. and Rothauer, D. and Mecking, S.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85100894748&doi=10.1038%2fs41586-020-03149-9&partnerID=40&md5=6a27232ca496cc788748987f36259405

Chemical Materials Science, Department of Chemistry, University of Konstanz, Konstanz, Germany

Plastics are key components of almost any technology today. Although their production consumes substantial feedstock resources, plastics are largely disposed of after their service life. In terms of a circular economy1–8, reuse of post-consumer sorted polymers (‘mechanical recycling’) is hampered by deterioration of materials performance9,10. Chemical recycling1,11 via depolymerization to monomer offers an alternative that retains high-performance properties. The linear hydrocarbon chains of polyethylene12 enable crystalline packing and provide excellent materials properties13. Their inert nature hinders chemical recycling, however, necessitating temperatures above 600 degrees Celsius and recovering ethylene with a yield of less than 10 per cent3,11,14. Here we show that renewable polycarbonates and polyesters with a low density of in-chain functional groups as break points in a polyethylene chain can be recycled chemically by solvolysis with a recovery rate of more than 96 per cent. At the same time, the break points do not disturb the crystalline polyethylene structure, and the desirable materials properties (like those of high-density polyethylene) are fully retained upon recycling. Processing can be performed by common injection moulding and the materials are well-suited for additive manufacturing, such as 3D printing. Selective removal from model polymer waste streams is possible. In our approach, the initial polymers result from polycondensation of long-chain building blocks, derived by state-of-the-art catalytic schemes from common plant oil feedstocks, or microalgae oils15. This allows closed-loop recycling of polyethylene-like materials. © 2021, The Author(s), under exclusive licence to Springer Nature Limited.

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Plastic recycling in a circular economy: determining environmental performance through an LCA matrix model approach

Waste Management

Schwarz, A. E., Ligthart, T. N., Bizarro, D. G., De Wild, P., Vreugdenhil, B., & van Harmelen, T.

To ensure a circular economy for plastics, insights in the environmental impacts of recycling and optimal
recycling choices for specific plastic polymers are crucial. This was obtained by determining the environmental
performance of 10 selected recycling technologies with varying TRL levels, using the chemical
properties of the top 25 produced polymers in Europe. The results were collected in a life cycle assessment
(LCA) ‘matrix’ model. To simulate realistic plastic recycling challenges, case studies of PE/PP foils
from municipal waste and ABS plastic with brominated flame retardants were developed, to be used
as an addition to the LCA matrix model results. Potential emission reduction was assessed by combining
LCA matrix outcomes with European polymer demand data. The LCA matrix model illustrates that potential
environmental performance of recycling technologies varied strongly per polymer type and did not
always follow the state-of-the-art recycling hierarchy. Commodity plastics performed well with tertiary
recycling technologies, such as gasification and pyrolysis to monomers; secondary mechanical recycling
was outperformed. A focus on primary recycling is environmentally beneficial for most engineering and
high performance plastics. To enhance the performance of primary recycling technologies, a higher purity
and improved sorting is required. As demonstrated in the case studies, low sorting efficiencies due to
impurities reduces positive environmental impacts. Hence, optimal environmental performance of recycling
is obtained where pre-treatment (sorting, cleaning) is adapted to the recycling technology.
According to the model, recycling the 15 most demanded polymers in Europe reduces CO2 emissions from
plastics by 73% or 200 Mtonne CO2 eq.

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Preliminary evaluation of plasmix compound from plastics packaging waste for reuse in bituminous pavements

Sustainability

Celauro, C. and Teresi, R. and Graziano, F. and Mantia, F.P.L. and Protopapa, A.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85101882060&doi=10.3390%2fsu13042258&partnerID=40&md5=14c9964ea14f1a7e109a0f46f0288e1b

["Dipartimento di Ingegneria, Università degli Studi di Palermo, Palermo, 90100, Italy", "INSTM, Italian National Interuniversity Consortium of Materials Science and Technology, Via Giusti 9, Florence, 50125, Italy", "COREPLA, Italian National Consortium for the Collection and Recycling of Plastic packages, Milan, 20100, Italy"]

Finding an appropriate technical solution for reusing waste plastics is crucial for creating a circular plastic economy. Although mechanical recycling is the best option for recycling post-consumer plastics, some heterogeneous mixed plastics cannot be recycled to produce secondary material due to their very low properties. In this case, alternative routes should be considered in order to limit their disposal as much as possible. Therefore, in order to solve the environmental problems in the landfills of plastic waste recycling, and to improve the mechanical performance of bitumen for road pavement, the reuse of these post-consumer plastic wastes are preliminarily evaluated for the modification of bitumen for road use. The field of polymers used so far and widely studied concerns virgin materials, or highly homogeneous materials, in case of recycled plastics. In this work, a highly heterogeneous mixed plastic—Plasmix—from the separate collection in Italy, is used as a bitumen modifier for road construction. The research focused on the dry (into the mixture) and wet (into the binder) addition of different content of the Plasmix compound, with the aim of assessing the feasibility of the modification itself. Results of the mechanical tests carried out prove an increase in performance and that there is a potential of the addition of the Plasmix compound both for binder and mixture modifications. Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

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Towards sustainable concrete composites through waste valorisation of plastic food trays as low-cost fibrous materials

Sustainability

Mohammadhosseini, H. and Alyousef, R. and Tahir, M.M.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85102121177&doi=10.3390%2fsu13042073&partnerID=40&md5=31100519b8f7035f5193707bd9203045

["Institute for Smart Infrastructure and Innovative Construction (ISIIC), School of Civil Engineering, Universiti Teknologi Malaysia (UTM), Skudai, Johor, 81310, Malaysia", "Department of Civil Engineering, Prince Sattam Bin Abdulaziz University, Alkharj, 16273, Saudi Arabia"]

Recycling of waste plastics is an essential phase towards cleaner production and circular economy. Plastics in different forms, which are non-biodegradable polymers, have become an indispensable ingredient of human life. The rapid growth of the world population has led to increased demand for commodity plastics such as food packaging. Therefore, to avert environment pollution with plastic wastes, sufficient management to recycle this waste is vital. In this study, experimental investigations and statistical analysis were conducted to assess the feasibility of polypropylene type of waste plastic food tray (WPFT) as fibrous materials on the mechanical and impact resistance of concrete composites. The WPFT fibres with a length of 20 mm were used at dosages of 0-1% in two groups of concrete with 100% ordinary Portland cement (OPC) and 30% palm oil fuel ash (POFA) as partial cement replacement. The results revealed that WPFT fibres had an adverse effect on the workability and compressive strength of concrete mixes. Despite a slight reduction in compressive strength of concrete mixtures, tensile and flexural strengths significantly enhanced up to 25% with the addition of WPFT fibres. The impact resistance and energy absorption values of concrete specimens reinforced with 1% WPFT fibres were found to be about 7.5 times higher than those of plain concrete mix. The utilisation of waste plastic food trays in the production of concrete makes it lowcost and aids in decreasing waste discarding harms. The development of new construction materials using WPFT is significant to the environment and construction industry. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

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Pilot-scale composting test of polylactic acid for social implementation

Sustainability

Kawashima, N. and Yagi, T. and Kojima, K.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85100665645&doi=10.3390%2fsu13041654&partnerID=40&md5=515b4905ac097ab43e58e2befcd844b0

Mitsui Chemicals, Inc, 1-5-2 Higashi-Shimbashi, Minato-ku, Tokyo, 105-7122, Japan

The chemical industry and subsequent value chain of plastics are facing significant challenges from the viewpoints of resource conversion and environmental burden. Now is the time to explore the future direction of plastics, which will require an integrated scheme using resource cir-culation, carbon neutrality, and a social system to promote after-use treatment under the concept of a circular economy. Polylactic acid (PLA) should help reduce greenhouse gas (GHG) emissions as a biobased material and contribute to waste management after use due to its biodegradability if managed properly. That is, it will be necessary to treat biodegradable products appropriately in closed systems such as composting facilities after use and recovery. To realize the implementation of fully approved composting facilities in society, simply evaluating biodegradability in the laboratory is insufficient. In this study, a pilot-scale test using PLA under actual composting conditions was con-ducted in accordance with both international standards and domestic evaluation methods. The results not only confirm its biodegradability and disintegration, but also demonstrate that the presence of a biodegradable plastic product has a negligible impact on the composting process. The obtained compost did not adversely affect plant germination or growth, demonstrating its safety and high quality. Such a multifaceted perspective makes this study unique and useful for creating a social framework. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

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Processability of different polymer fractions recovered from mixed wastes and determination of material properties for recycling

Polymers

Möllnitz, S. and Feuchter, M. and Duretek, I. and Schmidt, G. and Pomberger, R. and Sarc, R.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85100458974&doi=10.3390%2fpolym13030457&partnerID=40&md5=03a927de29e8555b019e9f5fbf1a72d7

["Department of Environmental and Energy Process Engineering, Chair of Waste Processing Technology and Waste Management, Montanuniversitaet Leoben � Franz�Josef�Straße 18, Leoben, 8700, Austria", "Department of Polymer Engineering, Chair of Materials Science and Testing of Polymers, Montanuniversi-taet Leoben�Otto Glöckel�Straße 2, Leoben, 8700, Austria", "Department of Polymer Engineering, Chair of Polymer Processing, Montanuniversitaet Leoben � Otto Glöckel�Straße 2, Leoben, 8700, Austria", "Saubermacher Dienstleistungs AG, Hans�Roth�Straße 1, Feldkirchen bei Graz, 8073, Austria"]

To achieve future recycling targets and CO2 and waste reduction, the transfer of plastic contained in mixed waste from thermal recovery to mechanical recycling is a promising option. This requires extensive knowledge of the necessary processing depth of mixed wastes to enrich plastics and their processability in polymer processing machines. Also, the selection of a suitable processing method and product application area requires appropriate material behaviour. This paper investi-gates these aspects for a commercial processed, mixed waste, and two different mixed polyolefin fractions. The wastes are processed at different depths (e.g., washed/not washed, sorted into poly-ethylene, polypropylene, polyethylene terephthalate, polystyrene/unsorted) and then either ho-mogenised in the extruder in advance or processed heterogeneously in the compression moulding process into plates. The produced recyclates in plate form are then subjected to mechanical, thermal, and rheological characterisation. Most investigated materials could be processed with simple compression moulding. The results show that an upstream washing process improves the achievable material properties, but homogenisation does not necessarily lead to an improvement. It was also found that a higher treatment depth (recovery of plastic types) is not necessary. The investigations show that plastic waste recovery with simple treatment from mixed, contaminated wastes into at least downcycling products is possible. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

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Barriers and enablers to buying biodegradable and compostable plastic packaging

Sustainability

Allison, A.L. and Lorencatto, F. and Michie, S. and Miodownik, M.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85100479715&doi=10.3390%2fsu13031463&partnerID=40&md5=a47012e4caf1897812fe332e21ca7ce3

["UCL Plastic Waste Innovation Hub, University College London, London, WC1E 6BT, United Kingdom", "UCL Centre for Behaviour Change, University College London, London, WC1E 6BT, United Kingdom"]

Biodegradable and compostable plastic packaging (BCPP) has the potential to reduce a global plastic waste problem. We aimed to identify influences on buying BCPP as a basis for designing strategies that enable BCPP’s environmental benefits. Using a UK-focused citizen science dataset, we thematically analysed 610 survey responses to a question exploring reasons for BCPP purchase. Themes are categorised as barriers and enablers and according to the components of the Capability, Opportunity, Motivation, and Behaviour (COM-B) model of behaviour. Key barriers concerned: psychological capability (not understanding terminology used to label packaging, not taking notice of packaging, and preferring other types of packaging and product qualities)

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Method development and evaluation of pyrolysis oils from mixed waste plastic by GC-VUV

Journal of Chromatography A

Dunkle, M.N. and Pijcke, P. and Winniford, W.L. and Ruitenbeek, M. and Bellos, G.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85098184374&doi=10.1016%2fj.chroma.2020.461837&partnerID=40&md5=6e9bf833861d91b6f75229fa17a3032c

["Dow Benelux BV, Herbert H. Dowweg 5, Hoek, 4542 NM, Netherlands", "The Dow Chemical Company, 230 Abner Jackson ParkwayFreeport TX 77566, United States"]

The conversion of waste streams into a useable material through a recycling process is a hot topic. Waste streams can originate from domestic and industrial sources and range from plastic waste to medical waste to various industrial waste streams, both solid and liquid. In addition to waste circularity, circularity for bio-based waste streams and renewable sources are also being investigated. To simplify this complexity, this article presents a case study evaluating the output from the feedstock recycling of plastic waste originating from municipal solid waste. Plastic waste entering the environment is undesired, and many initiatives are working towards a plastics circular economy. Once disposed of, ideally, plastic waste should be either re-used or recycled in order to avoid incineration or disposal in landfills. Recycling waste plastic can occur either via mechanical recycling or feedstock (chemical) recycling, where feedstock recycling can occur for example, through gasification or pyrolysis technologies. This article will focus only on the oils obtained from the pyrolysis of mixed waste plastic. The output from pyrolysis has a different composition than traditional fossil-based hydrocarbon streams, and therefore, must be evaluated to correctly process as feedstock. The authors have previously shown that gas chromatography coupled to vacuum ultraviolet detection (GC-VUV) provides accurate identification and quantification of the hydrocarbon composition (paraffins, isoparaffins, olefins, naphthenes, and aromatics – PIONA) of fossil-based liquid hydrocarbon streams.1 Therefore, GC-VUV was evaluated for analysis of the pyrolysis oils from plastic waste. Using an in-house modified spectral library in combination with the PIONA+ software, accurate identification and quantification of the hydrocarbon composition of pyrolysis oils from C4 through C30+ was possible with a limit of detection of 0.1 wt.%. To the best of our knowledge, this article is the first example of accurate PIONA-type quantification of pyrolysis oils by GC-VUV. © 2020

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Evaluation of circular economy potential of plastic waste in Sri Lanka

Environmental Quality Management

Samarasinghe, K. and Pawan Kumar, S. and Visvanathan, C.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85101248287&doi=10.1002%2ftqem.21732&partnerID=40&md5=cb40263caef9aa569153e80ccb52215e

School of Environment, Resources and Development, Asian Institute of Technology, Pathum Thani, Thailand

With increasing industrialization and high growing coastal population in Sri Lanka, plastic waste in municipal solid waste has increased tremendously over the past few decades. Plastic consumption in Sri Lanka is increasing at 16% annually with a current consumption of 265,000 megagram (Mg) per annum. If the current trends continue, a large amount of plastics will end up in an open environment threatening natural ecosystems. An attempt was carried out to understand the plastic material flow within Sri Lanka in the year 2017. Through material flow analysis, plastic material flow cycle consisting of nine processes was categorized. The plastic collection and recycling efficiencies were found to be 33% and 3%, respectively. The total quantity of plastics washed into the sea could have been approximated to 69,427 Mg. The per capita contribution is about 3.3 kg. With the integration of the plastic waste circular economy to the Renewable Energy Development Plan (2019–2025) of Sri Lanka, various scenarios were developed for the year 2025. Source segregation of plastic wastes, landfill mining to recover nonrecyclable plastics for energy production, and integration of formal and informal sectors are the three key recommendations to transform to a more vibrant circular economy. © 2021 Wiley Periodicals LLC

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Exploring the circular supply chain to reduce plastic waste in singapore

Logforum

Chen, Z. and Tan, A.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85104810134&doi=10.17270%2fJ.LOG.2021.564&partnerID=40&md5=54995f9a467b232d07bd0275f892e542

["Curtin University, Singapore", "Curtin university, Faculty of Management, Singapore"]

Background: The COVID-19 changes our lifestyle and triggers the rapid development of online shopping resulting in massive use of plastic for packaging for each parcel. Hence, plastic waste management has become a worrying concern in some countries. This research proposes that the circular supply chain could be a way to reduce plastic waste with regards to the triple bottom line: economy, social, and environment. It applies the life-cycle assessment (LCA) and target sampling method. Methods: The data about plastic waste, including the production, consumption, and the end-of-life stage from target developed countries were collected and analyzed. By comparing practices applied in Germany and South Korea, this research investigates a framework for both the upstream and the downstream through the implementation of the 4R concept: reduce, reuse, recycle, and recovery. Results and conclusions: This study provides new insights of the circular supply chain from the perspective of the government, producers, and consumers and call for more attention from the demand perspective (involving more efforts from authorities and consumers) of the plastic industry instead of only concentrating on the supply perspective. © Wyższa Szkoła Logistyki, Poznań, Polska.

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Plastics: friends or foes? The circularity and plastic waste footprint

Energy Sources, Part A: Recovery, Utilization and Environmental Effects

Klemeš, J.J. and Fan, Y.V. and Jiang, P.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85089134445&doi=10.1080%2f15567036.2020.1801906&partnerID=40&md5=1f031b220eb0ab68bb3c5ed2bc5b000f

["Sustainable Process Integration Laboratory – SPIL, NETME Centre, Faculty of Mechanical Engineering, Brno University of Technology - VUT Brno, Brno, Czech Republic", "Department of Systems Science, Institute of High Performance Computing, Singapore, Singapore"]

The plastics are becoming one of the most discussed topics in media and research. They have been branded sometimes as evil, which has to be replaced, in some cases at any cost. However, an equitable analysis and assessment are needed comparing all pros and cons based on environmental footprints quantification with a complete life cycle assessment. These should include assessment of possible health risks, consumed energy, released emissions and effluents, as well as consumption of raw materials, water and dealing with the wastewater. The assessment of recyclability, reprocessing and environmental burden of disposal phases are also needed. This presented work tends to contribute to the discussion of what recommendations should be developed to the industry and business to minimize the environmental impacts. A novel Plastic Waste Footprint is proposed to understand the net potential impacts of plastic and to facilitate the decision making for plastic replacement. This study highlighted that plastic could be a friend if the Circular Economy (CE) is appropriately followed. Reduction (refrain, redesign/reduce, reuse, repair, refurbish, remanufacture, repurpose), recycle and recovery (no leaking into the ocean or other streams) play the decisive roles to minimize and recover the embodied energy, promoting sustainable plastic values chain. Policy to regulate/encourage manufacturers toward sustainable practice (taxation, end of life collection, an incentive of using secondary raw materials) and education (refrain, reuse, separation and recycle) on the potential users are important from not evolving the plastic from friend with high functionality to foe. © 2020 Taylor & Francis Group, LLC.

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Influence of pre-screening on down-stream processing for the production of plastic enriched fractions for recycling from mixed commercial and municipal waste

Waste Management

Möllnitz, S. and Küppers, B. and Curtis, A. and Khodier, K. and Sarc, R.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85094599392&doi=10.1016%2fj.wasman.2020.10.007&partnerID=40&md5=7e15302766a66b950d4b583c542a05cb

["Department of Environmental and Energy Process Engineering, Chair of Waste Processing Technology and Waste Management, Montanuniversitaet Leoben – Franz-Josef-Straße 18, Leoben, 8700, Austria", "Department of Environmental and Energy Process Engineering

The use of plastic waste as resource gains more and more attention. In this context, material recycling is
especially focused on packaging plastics. Further waste streams that contain a significant amount of plastics
are mixed commercial and municipal solid waste. To assess the potential of plastics for recycling and
energy recovery from these material streams large-scale experiments were conducted. The potential of
mechanical pre-processing with the aim of generating a 3D-plastics pre-concentrate was assessed. The
focus of these investigations was put on the relevance of the screening stage and its influence on
down-stream material processing via ballistic separation and sensor-based sorting. Results demonstrate
not only that the screening of both waste streams leads to enrichment of plastics in coarse particle size
ranges (especially >80 mm) and transfer of contaminants, organics and minerals to fine fractions (especially
<10 mm), but also that sensor-based sorting performance can be significantly enhanced due to
cleaning effects on plastics, induced by the material circulation and the resulting interparticle friction
in a drum screen. On the downside, the material rotation in a drum screen leads to tail-formation that
can create plant down-time through clogging as well as material losses and impairment of preconcentrates.

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Household plastic waste habits and attitudes: A pilot study in the city of Valencia

Waste Management and Research

Roche Cerasi, I. and Sánchez, F.V. and Gallardo, I. and Górriz, M.Ã�. and Torrijos, P. and Aliaga, C. and Franco, J.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85102946906&doi=10.1177%2f0734242X21996415&partnerID=40&md5=aedafa9d090259aab568356e2ec2a50e

["Department of Mobility and Economics, SINTEF Community, Norway", "ITENE, Instituto Tecnológico del Embalaje, Transporte y Logística, Spain", "SAV, Agricultores de la Vega de Valencia, Spain"]

Bearing in mind that only 42% of plastic packaging post-consumer waste is recycled in Europe, the European Directive 2018/852 established the key target of a 55% plastic packaging waste recycling rate by 2030. For this reason, PlastiCircle, funded by the European Union’s Horizon 2020 research and innovation program project, aims to foster the recycling of packaging, improve all stages of the waste collection, and promote responsible consumption. Three European cities have been selected as locations for pilot implementation: Valencia (Spain), Utrecht (The Netherlands) and Alba Iulia (Romania). The main objective of the present study has been to evaluate the participants’ opinion and attitudes on plastic recycling. This paper presents the results from the district of San Marcelino in the city of Valencia, the first PlastiCircle pilot to face the challenges of encouraging households to participate more in plastic waste sorting and recycling. © The Author(s) 2021.

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Waste plastics derived graphene nanosheets for supercapacitor application

Materials and Manufacturing Processes

Karakoti, M. and Pandey, S. and Jangra, R. and Dhapola, P.S. and Singh, P.K. and Mahendia, S. and Abbas, A. and Sahoo, N.G.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85092761183&doi=10.1080%2f10426914.2020.1832680&partnerID=40&md5=74b13194977461b8253b74a6bda6af2a

["Prof. Rajendra Singh Nanoscience and Nanotechnology Centre, Department of Chemistry, DSB Campus, Kumaun University, Nainital, India", "Department of Physics, Kurukshetra University, Kurukshetra, India", "Material Research Laboratory, School of Basic Sciences and Research, Sharda University, Greater Noida, India", "School of Chemical and Biomolecular Engineering, The University of Sydney, Sydney, Australia"]

Given the non-biodegradable nature of plastic, its recycling and upcycling are critical to ensure effective waste management and resource conservation, with a cradle-to-cradle approach. Herewith, we report a low-effort and nature-friendly upcycling route for plastic waste to manufacture large quantities of graphene nanosheets (GNs) via a two-stage pyrolysis process. To analyze the utility of GNs synthesized by this process, their supercapacitive behavior was studied over different current collectors such as copper tape (CuT), indium tin oxide glass (ITO), graphite sheet (GS), and aluminum sheet (AlS) in PVA-H3PO4 gel electrolyte. Our findings confirm that the AlS current collector displayed superiority and demonstrated the highest specific capacitance of 38.78 F/g with the plastic waste GNs. Thus, the present study shows a cost-effective and sustainable option for propelling a circular economy through waste plastic upcycling with energy storage applications. © 2020 Taylor & Francis.

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Challenges and strategies for effective plastic waste management during and post COVID-19 pandemic

Science of the Total Environment

Vanapalli, K.R. and Sharma, H.B. and Ranjan, V.P. and Samal, B. and Bhattacharya, J. and Dubey, B.K. and Goel, S.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85089583676&doi=10.1016%2fj.scitotenv.2020.141514&partnerID=40&md5=d74189f8c58adb00309ca62908f09fac

["School of Environmental Science and Engineering, Indian Institute of Technology, Kharagpur, West Bengal 721302, India", "Department of Civil Engineering, Indian Institute of Technology, Kharagpur, West Bengal 721302, India", "Department of Mining Engineering, Indian Institute of Technology, Kharagpur, West Bengal 721302, India"]

The advent of the COVID-19 pandemic has enhanced the complexities of plastic waste management. Our improved, hyper-hygienic way of life in the fear of transmission has conveniently shifted our behavioral patterns like the use of PPE (Personal protective equipment), increased demand for plastic-packaged food and groceries, and the use of disposable utensils. The inadequacies and inefficiencies of our current waste management system to deal with the increased dependence on plastic could aggravate its mismanagement and leakage into the environment, thus triggering a new environmental crisis. Mandating scientific sterilization and the use of sealed bags for safe disposal of contaminated plastic wastes should be an immediate priority to reduce the risk of transmission to sanitation workers. Investments in circular technologies like feedstock recycling, improving the infrastructure and environmental viability of existing techniques could be the key to dealing with the plastic waste fluxes during such a crisis. Transition towards environmentally friendly materials like bioplastics and harboring new sustainable technologies would be crucial to fighting future pandemics. Although the rollbacks and relaxation of single-use plastic bans may be temporary, their likely implications on the consumer perception could hinder our long-term goals of transitioning towards a circular economy. Likewise, any delay in building international willingness and participation to curb any form of pollution through summits and agendas may also delay its implementation. Reduction in plastic pollution and at the same time promoting sustainable plastic waste management technologies can be achieved by prioritizing our policies to instill individual behavioral as well as social, institutional changes. Incentivizing measures that encourage circularity and sustainable practices, and public-private investments in research, infrastructure and marketing would help in bringing the aforementioned changes. Individual responsibility, corporate action, and government policy are all necessary to keep us from transitioning from one disaster to another. © 2020 Elsevier B.V.

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Wet-mechanical processing of a plastic-rich two-dimensional-fraction from mixed wastes for chemical recycling

Waste Management and Research

Selina, M. and Markus, B. and Daniel, S. and Renato, S.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85101795698&doi=10.1177%2f0734242X21996435&partnerID=40&md5=0fd6f05fdb380f5be5285f144b6be0ab

["Department of Environmental and Energy Process Engineering, Chair of Waste Processing Technology and Waste Management, Montanuniversitaet Leoben, Leoben, Austria", "Circulyzer GmbH, Leoben, Austria"]

The recycling of source separated polyolefins (POs) (e.g., light weight packaging waste) is already state of the art. Therefore, further plastic materials contained in mixed wastes have become more important due to increasing legal pressure. Mixed commercial and municipal solid wastes contain large quantities of POs. These mixed wastes would usually be treated in waste incinerators or processed to refuse-derived fuel for cement plants. Large-scale experiments were conducted to assess the potential of such POs from these waste streams for recycling processes. The potential and applicability of a dry-mechanical and subsequently wet-mechanical (Wet-mechanical) processing with the aim of generating a PO concentrate for chemical recycling purposes was assessed. These investigations’ focus was put on the centrifugal force separator technology as the core element of Wet-mechanical processing. In addition to the input material, all output materials and process water streams were chemically and physically characterized to estimate potential treatment or recycling paths. Results demonstrate that a two-stage purification is necessary to produce POs with sufficient purity out of both wastes. Chlorine and heavy metal levels are simultaneously reduced. The increased quantity of impurities only slightly changes the density of the process waters. Process water analyses show that wastewater treatment is necessary before discharge into a receiving water or sewage treatment plant. The sediment does not fulfil any hazard-relevant properties, and different thermal treatment options are possible. © The Author(s) 2021.

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The future of UK plastics recycling: One Bin to Rule Them All

Resources, Conservation and Recycling

Burgess, M. and Holmes, H. and Sharmina, M. and Shaver, M.P.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85091978279&doi=10.1016%2fj.resconrec.2020.105191&partnerID=40&md5=a29fe7525c4f259228f49cf530b1e669

["Sustainable Consumption Institute, Booth Street West, Manchester, M15 6 PB, United Kingdom", "Tyndall Centre for Climate Change Research, University of ManchesterM1 3BB, United Kingdom", "Department of Materials, Henry Royce Institute, University of ManchesterM1 3BB, United Kingdom"]

The use of plastics, and even the existence of this versatile material, has been increasingly demonised in the UK. Public campaigns exist to expand use of recyclable cups and to eliminate plastic straws. Retailers supplying 80% of the market are now members of the UK Plastics Pact, with goals to ensure that products are designed to be recycled, that recycling takes place, and that more recyclate is used in new products. Public awareness has not translated into action, as domestic collection rates for discarded plastics remain pitifully low. We started with a systems-wide vision that these rates can only be increased if all household plastic recycling is made easy and consistent christened ‘One Bin to Rule Them All’ - and used this premise as a starting point to examine the implications of a fully mixed plastics waste stream entering the supply chain. An agenda for future research was developed through 25 interviews with senior industrial and commercial management and a cross-sector workshop. We determined that if improved household collection rates are to translate into significantly improved recycling rates, rapid progress is required in four areas: standardisation (materials, kerbside collections, waste sorting), infrastructure investment, development of cross-supply chain business models and creation of higher value recyclate. Creating a harmonised national solution to plastic waste sorting is critically dependent on maintaining value in discarded plastics. This in turn reduces plastic leakage into the environment. Enabling this value-based scenario in the UK would form a best-practice model for other regions. © 2020 Elsevier B.V.

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Effect of cyclic reprocessing on nylon 12 under injection molding: working toward more efficient recycling of plastic waste

Materials Today Sustainability

Nur-A-Tomal, M.S. and Pahlevani, F. and Handoko, W. and Cholake, S.T. and Sahajwalla, V.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85098673048&doi=10.1016%2fj.mtsust.2020.100056&partnerID=40&md5=bd7271ef26e768a0385c86844b9ea254

Centre for Sustainable Materials Research and Technology, SMaRT@UNSW, School of Materials Science and Engineering, UNSW, Sydney, NSW 2052, Australia

Owing to the limitations that impede traditional recycling technologies, only a small percentage of waste plastic is currently recycled. Most recycling processes create products that are poor in terms of performance and value. To produce high-quality products from plastic waste and bring back these valuable materials to the economy after their end of life, it is important to know the change in polymer properties during cyclic reprocessing. During this study, investigations were conducted to create a profound understanding of the effects of cyclic reprocessing on the properties of nylon 12. First, the flow behavior of molten nylon 12 in the injection mold was studied. Then, optimized processing conditions were established by investigating the tensile and impact strength of molded products. Finally, the influence of cyclic reprocessing on the material was assessed through tensile test, impact test, thermal analysis, X-ray diffractometry, and Fourier transform infrared (FTIR) spectroscopy. The obtained results indicate that nylon 12 could be recycled at least four times without drastically changing its properties. A slight change in the tensile strength, impact strength, glass transition temperature, and percentage of crystallinity was observed as the number of reprocessing cycles increases. Furthermore, no significant variation of FTIR spectra indicated that multiple reprocessing had not changed the molecular structure of nylon 12. Together, the various elements of this research could be helpful in developing more effective and efficient recycling processes for plastic waste. © 2020 Elsevier Ltd

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Techno-economic assessment and comparison of different plastic recycling pathways: A German case study

Journal of Industrial Ecology

Volk, R. and Stallkamp, C. and Steins, J.J. and Yogish, S.P. and Müller, R.C. and Stapf, D. and Schultmann, F.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85105048849&doi=10.1111%2fjiec.13145&partnerID=40&md5=0f1c66e8c53c09a764db64a602dfbcad

["Karlsruhe Institute of Technology (KIT), Institute for Industrial Production (IIP), Germany", "Karlsruhe Institute of Technology (KIT), Institute for Technical Chemistry (ITC), Germany"]

Greenhouse gas (GHG) emissions need to be reduced to limit global warming. Plastic production requires carbon raw materials and energy that are associated today with predominantly fossil raw materials and fossil GHG emissions. Worldwide, the plastic demand is increasing annually by 4%. Recycling technologies can help save or reduce GHG emissions, but they require comparative assessment. Thus, we assess mechanical recycling, chemical recycling by means of pyrolysis and a consecutive, complementary combination of both concerning Global Warming Potential (GWP) [CO2e], Cumulative Energy Demand (CED) [MJ/kg], carbon efficiency [%], and product costs [€] in a process-oriented approach and within defined system boundaries. The developed techno-economic and environmental assessment approach is demonstrated in a case study on recycling of separately collected mixed lightweight packaging (LWP) waste in Germany. In the recycling paths, the bulk materials polypropylene (PP), polyethylene (PE), polyvinylchloride (PVC), and polystyrene (PS) are assessed. The combined mechanical and chemical recycling (pyrolysis) of LWP waste shows considerable saving potentials in GWP (0.48 kg CO2e/kg input), CED (13.32 MJ/kg input), and cost (0.14 €/kg input) and a 16% higher carbon efficiency compared to the baseline scenario with state-of-the-art mechanical recycling in Germany. This leads to a combined recycling potential between 2.5 and 2.8 million metric tons/year that could keep between 0.8 and 2 million metric tons/year additionally in the (circular) economy instead of incinerating them. This would be sufficient to reach both EU and German recycling rate targets (EC 2018). This article met the requirements for a gold-silver JIE data openness badge described at http://jie.click/badges. © 2021 The Authors. Journal of Industrial Ecology published by Wiley Periodicals LLC on behalf of Yale University

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Optimized production of single-use plastic-Eucalyptus wood char composite for application in soil

Journal of Cleaner Production

Vanapalli, K.R. and Bhattacharya, J. and Samal, B. and Chandra, S. and Medha, I. and Dubey, B.K.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85090237567&doi=10.1016%2fj.jclepro.2020.123968&partnerID=40&md5=7db6ae1875049f10120b9d9c5eca76c3

["School of Environmental Science and Engineering, Indian Institute of Technology, Kharagpur, West Bengal 721302, India", "Department of Mining Engineering, Indian Institute of Technology, Kharagpur, West Bengal 721302, India", "Department of Civil Engineering, Indian Institute of Technology, Kharagpur, West Bengal 721302, India", "Zelence Industries Private Limited, Kharagpur, India"]

Co-pyrolysis of Eucalyptus wood (EW) and Single-use plastic (SUP) can be a sustainable and green technological option ensuring optimum resource recovery and plastic waste management in a circular economy. This study aims to optimize the variables of pyrolysis [temperature (300, 400, 500, 600 °C), residence time (90, 120, 150 min), and proportion of plastic (w/w - 0.25, 0.33)] for application of SUP - EW char composite in soil. Statistical analysis showed that all three process variables had significant influence on properties of the char. With temperature and residence time, the char became dense, carbonaceous, ash-rich, aromatic, and alkaline for both the proportions of SUP in the feed. Further characterization also revealed that the highest plant extractable concentrations of major nutrients, cation exchange capacity, and electrical conductivity of char composite were recorded with temperatures of 400–500 °C, residence time of 120 min, and 33% (w/w) of SUP. The surface morphology analysis revealed the char to have a porous structure with a coating of plastic at lower temperatures of 300 °C and an increase in microporosity at higher temperatures of 500, 600 °C. Significant positive correlations between radicle root growth and prominent plant growth parameters observed through seed germination test indicate the char's potential applicability in soil. The optimized process parameters of char obtained through regression modeling for application in soil were 415.2 °C, 125.2 min, and 0.325 (w/w) proportion of SUP. The highest mean seed length of ≈17.5 cm observed at 400 °C, 120 min, and 0.33 (w/w) proportion of SUP was consistent with these optimized parameters. Soil incubation test further showed that amendment with optimized char composite significantly improved its properties with a 3.7-fold increase in soil fertility index at 5% rate of application. So, the application of optimized SUP - EW char composite could significantly improve the properties of soil while promoting greener sustainable development through ideal utilization of the so far mismanaged waste resources. © 2020 Elsevier Ltd

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Experimental investigation of the behavior of soil reinforced with waste plastic bottles under cyclic loads

Transportation Geotechnics

Moghaddas Tafreshi, S.N. and Parvizi Omran, M. and Rahimi, M. and Dawson, A.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85095435468&doi=10.1016%2fj.trgeo.2020.100455&partnerID=40&md5=a6a67a56f1e25094c1d5d2b97a89eaa9

["Department of Civil Engineering, K.N. Toosi University of Technology, Valiasr St., Mirdamad Cr., Tehran, Iran", "Nottingham Transportation Engineering Centre, University of Nottingham, Nottingham, United Kingdom"]

The low natural degradation rate of plastic products makes the recycling or disposal of increasing post-consumer plastic materials, including Plastic Polyethylene Terephthalate (PET) bottles, a global concern. The current capacity of recycling programs for absorbing annual waste PET materials in environmentally friendly ways is limited. As a novel beneficial option, the cellular form of post-consumer bottles might act to provide sufficient confinement for infill soil and hence provide a technique by which the behavior of foundation beds under applied loads could be improved. In this study, a series of full-scale tests were conducted on unreinforced and PET (Plastic Polyethylene Terephthalate) bottle reinforced beds. For each test 100 cycles of 400 kPa load followed by 400 cycles of 800 kPa load was applied to the pavement through loading plate. Experiments were performed in a 2200 × 2200 × 1000 mm test pit on a 300 mm diameter circular loading plate. Three different sizes (i.e., different external diameters and heights) of waste plastic (PET) bottles filled with soil were tested as a reinforcing element. In some tests, a single layer of HDPE (high-density polyethylene) geogrid layer over bottles reinforced zone was examined. The results showed improvement in all reinforcing arrangement, although improvement was slightly higher for smaller bottles. For the reinforced case, a lower settlement accumulation rate and a higher resilient (elastic) settlement was observed compared to the unreinforced condition. In the case of lower cyclic loading (400 kPa amplitude), an average 42% improvement occurred for the three bottle-reinforced scenarios, however this value was 179% for higher cyclic loading (800 kPa), indicating more benefits of bottle-reinforcement in the case of critically loaded conditions. An extra layer of geogrid over the bottle-reinforced zone increases load distribution area and prevents distortion of bottles, leading to as much as 82% more reduction in soil settlement compared to the case without geogrid. The combined use of bottles and single geogrid layer eliminates the need to multilayer geosynthetic reinforcement usage, helps the economy of the project besides avoiding the high cost of waste bottle disposal. © 2020 Elsevier Ltd

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Improvement of packaging circularity through the application of reusable beverage cup reuse models at outdoor festivals and events

Sustainability

Šuškevice, V. and Kruopien˙e, J.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85098594474&doi=10.3390%2fsu13010247&partnerID=40&md5=61c5010a7baba7dc2abfc2ef4c951911

Institute of Environmental Engineering, Kaunas University of Technology, Kaunas, LT-44249, Lithuania

Festivals generate huge amounts of waste during a short period of time, usually in three to four days. Single-use packaging is one of the dominant waste streams at the festivals. In order to minimize single-use plastic packaging waste generation and negative impacts on the environment, outdoor festivals apply alternative reusable cup systems and strategies. However, little studies have been made on how different reusable beverage cup reuse models can affect material circularity within certain festivals, and how it contributes to cup damage and loss. This article presents the results of a pilot study of different reusable cup reuse models within seven Lithuanian summer outdoor festivals. Three different models were applied and tested: A—only reusable cups, non-refundable model

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One-Pot Chemo-bioprocess of PET Depolymerization and Recycling Enabled by a Biocompatible Catalyst, Betaine

ACS Catalysis

Kim, D.H. and Han, D.O. and In Shim, K. and Kim, J.K. and Pelton, J.G. and Ryu, M.H. and Joo, J.C. and Han, J.W. and Kim, H.T. and Kim, K.H.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85105094292&doi=10.1021%2facscatal.0c04014&partnerID=40&md5=5147c709837a9a5ad5e19e12cbe0f870

["Department of Biotechnology, Graduate School, Korea University, Seoul, 02841, South Korea", "School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology, Pohang, Gyeongbuk, 37673, South Korea", "California Institute for Quantitative Biosciences, University of California, Berkeley, CA 94720, United States", "Bio-based Chemistry Research Center, Advanced Convergent Chemistry Division, Korea Research Institute of Chemical Technology, Daejeon, 34114, South Korea", "Department of Chemical Engineering, Pohang University of Science and Technology, Pohang, Gyeongbuk, 37673, South Korea"]

Poly(ethylene terephthalate) (PET) has been widely used in various industries due to its unique physical properties. However, PET causes major environmental problems globally due to its low degradability and recycling rate. Since it is nearly impossible to replace PET with other materials, an efficient approach for PET recycling is necessary for a circular economy. Herein, for a paradigm shift toward the approach for resource recovery of PET components, we developed an integrated process for depolymerizing PET and converting PET monomers to high-value products in a one-pot process. The key of our approach is the use of the biocompatible catalyst betaine in a glycolysis process that enables whole PET glycolysis slurry as a substrate to be directly applied to further bioprocesses. Based on the density functional theory (DFT) analysis, betaine effectively catalyzed PET depolymerization by two strong hydrogen interactions between betaine, EG, and PET as well as by the synergetic effect between the anion and cation groups of betaine. Through the glycolysis of PET with betaine and the optimized enzymatic hydrolytic process for the PET glycolysis slurry, PET was depolymerized to terephthalate (TPA, 31.0 g/L, 62.8%, mol/mol) and ethylene glycol (EG, 11.7 g/L, 63.3%, mol/mol) at high titers and high yields. This process was further applied to the bioconversion of TPA and EG present in the PET hydrolysate to protocatechuic acid (PCA) and glycolic acid (GLA), respectively. This one-pot chemo-bioprocess integrating chemical glycolysis, enzymatic hydrolysis, and bioconversion for PET depolymerization and recycling was suggested to be highly applicable to the upcycling of waste PET. © 2021 American Chemical Society.

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Determination of the composition and properties of PET bottles: Evidence of the empirical approach from Perm, Russia

Waste Management and Research

Polygalov, S. and Ilinykh, G. and Korotaev, V. and Stanisavljevic, N. and Batinic, B.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85104552508&doi=10.1177%2f0734242X211011222&partnerID=40&md5=24455aa764084cbaa1923d755684d194

["Environmental Protection Department, Perm National Research Polytechnic University, Perm, Russian Federation", "University of Novi Sad, Faculty of Technical Sciences, Department of Environmental Engineering, Novi Sad, Serbia"]

Efficient collection systems and information about the characteristics and quality of collected secondary plastic waste flows are of fundamental importance for the development of circular economies. In order to assess the effectiveness of the implementation of separate collection systems for plastic packaging, especially polyethylene terephthalate (PET) bottles, characteristic of the collected PET bottles in street mesh containers were studied in the city of Perm, Russia. The share of extraneous fractions was assessed and differentiation was carried out by volume, type of product, label presence, shape, content of solid and liquid impurities and colour. These results indicate that PET composition in different seasons is very similar, despite the assumption that the consumption of PET bottles in the spring and autumn seasons varies. In the mesh containers, up to 34% of the items were foreign objects, considering that only PET bottles should be collected. In each dimensional flow of PET bottles, the proportion of transparent bottles prevailed

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Genome analysis of the metabolically versatile Pseudomonas umsongensis GO16: the genetic basis for PET monomer upcycling into polyhydroxyalkanoates

Microbial Biotechnology

Narancic, T. and Salvador, M. and Hughes, G.M. and Beagan, N. and Abdulmutalib, U. and Kenny, S.T. and Wu, H. and Saccomanno, M. and Um, J. and O'Connor, K.E. and Jiménez, J.I.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85099051661&doi=10.1111%2f1751-7915.13712&partnerID=40&md5=d2073ca43aae48bc3109309590e7a7dc

["BiOrbic – Bioeconomy Research Centre, University College Dublin, Belfield, Dublin 4, Ireland", "UCD Earth Institute and School of Biomolecular and Biomedical Science, University College Dublin, Belfield, Dublin 4, Ireland", "Faculty of Health and Medical Sciences, University of Surrey, Guildford, GU2 7XH, United Kingdom", "UCD Earth Institute and School of Biology and Environmental Science, University College Dublin, Belfield, Dublin 4, Ireland", "Bioplastech Ltd., NovaUCD, Belfield Innovation Park, University College Dublin, Belfield, Dublin 4, Ireland", "Department of Life Sciences, Imperial College London, London, SW7 2AZ, United Kingdom"]

The throwaway culture related to the single-use materials such as polyethylene terephthalate (PET) has created a major environmental concern. Recycling of PET waste into biodegradable plastic polyhydroxyalkanoate (PHA) creates an opportunity to improve resource efficiency and contribute to a circular economy. We sequenced the genome of Pseudomonas umsongensis GO16 previously shown to convert PET-derived terephthalic acid (TA) into PHA and performed an in-depth genome analysis. GO16 can degrade a range of aromatic substrates in addition to TA, due to the presence of a catabolic plasmid pENK22. The genetic complement required for the degradation of TA via protocatechuate was identified and its functionality was confirmed by transferring the tph operon into Pseudomonas putida KT2440, which is unable to utilize TA naturally. We also identified the genes involved in ethylene glycol (EG) metabolism, the second PET monomer, and validated the capacity of GO16 to use EG as a sole source of carbon and energy. Moreover, GO16 possesses genes for the synthesis of both medium and short chain length PHA and we have demonstrated the capacity of the strain to convert mixed TA and EG into PHA. The metabolic versatility of GO16 highlights the potential of this organism for biotransformations using PET waste as a feedstock. © 2021 The Authors. Microbial Biotechnology published by Society for Applied Microbiology and John Wiley & Sons Ltd

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Evolution of the global polyethylene waste trade system

Ecosystem Health and Sustainability

Xu, W. and Chen, W.-Q. and Jiang, D. and Zhang, C. and Ma, Z. and Ren, Y. and Shi, L.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85086018157&doi=10.1080%2f20964129.2020.1756925&partnerID=40&md5=8f1af626d592042e7957e4e2d123a8dd

["Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, Fujian, China", "Xiamen Key Lab of Urban Metabolism, Xiamen, Fujian, China", "Middlebury College, Middlebury, VT, United States", "University of Chinese Academy of Sciences, Beijing, China", "Environmental Engineering Department, Montana Tech, Butte, MT, United States", "School of Economics and Management, Tongji University, Shanghai, China", "State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, China"]

Introduction: China’s import bans on solid wastes starting from 2017 have challenged the global trade system of plastic wastes, which remains poorly characterized. This study chooses polyethylene (PE) as a case and aims to map out the global trade networks of PE waste (GPETN) from 1976 to 2017. Outcomes: We find that the size and complexity of the GPETN had been growing until 2016. After the mid-1990s, PE waste basically flowed from developed economies, mainly the EU and the US, to developing economies such as China. Since 2001 when admitted into the WTO, China’s PE waste import surged until 2014 when it absorbed over 60% of global export. Regulations on solid waste import following the Green Fence campaign in 2013 resulted in substantial reductions in China’s import as well as the global export of PE waste after 2014. Several other developing economies, such as Malaysia, Turkey, and Vietnam, had transitioned to net importers, but their imports were insufficient to replace China as new recycling bases for PE waste. Conclusion: The results highlight the urgent need of a joint effort for developed and developing countries to build a stronger global circular economy system with sufficient capacity to treat PE waste locally. © 2020, © 2020 The Author(s). Published by Taylor & Francis Group and Science Press on behalf of the Ecological Society of China.

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Dynamic Material Flow Analysis of PET, PE, and PP Flows in Europe: Evaluation of the Potential for Circular Economy

Environmental Science and Technology

Eriksen, M.K. and Pivnenko, K. and Faraca, G. and Boldrin, A. and Astrup, T.F.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85097822069&doi=10.1021%2facs.est.0c03435&partnerID=40&md5=ae8f32452e87979562e08406a2010b33

["Department of Environmental Engineering, Technical University of Denmark, Bygningstorvet 115, Kgs. Lyngby, 2800, Denmark", "European Commission, Joint Research Centre, Edificio EXPO, C/Inca Garcilaso 3, Sevilla, E-41092, Spain"]

This study evaluates the potential circularity of PET, PE, and PP flows in Europe based on dynamic material flow analysis (MFA), considering product lifetimes, demand growth rates, and quality reductions of recycled plastic (downcycling). The circularity was evaluated on a baseline scenario, representing 2016 conditions, and on prospective scenarios representing key circularity enhancing initiatives, including (i) maintaining constant plastic consumption, (ii) managing waste plastic exports in the EU, (iii) design-for-recycling initiatives, (iv) improved collection, and (v) improved recovery and reprocessing. Low recycling rates (RR, 13-20%) and dependence on virgin plastic, representing 85-90% of the annual plastic demand, were demonstrated after 50 years in the baseline. Limited improvements were related to the individual scenarios, insufficient to meet existing recycling targets. However, by combining initiatives, RRs above 55%, where 75-90% was recycled in a closed loop, were demonstrated. Moreover, 40-65% of the annual demand could potentially be covered by recycled plastic. Maintaining a constant plastic demand over time was crucial in order to reduce the absolute dependence on virgin plastic, which was not reflected by the RR. Thus, focusing strictly on RRs and even whether and to which extent virgin material is substituted, is insufficient for evaluating the transition toward circularity, which cannot be achieved by technology improvements alone - the demand must also be stabilized. © 2020 American Chemical Society.

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Incorporation of recycled high-density polyethylene to polyethylene pipe grade resins to increase close-loop recycling and Underpin the circular economy

Journal of Cleaner Production

Juan, R. and Domínguez, C. and Robledo, N. and Paredes, B. and García-Muñoz, R.A.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85091490551&doi=10.1016%2fj.jclepro.2020.124081&partnerID=40&md5=3931e17508f7493b6e333f7630499585

["GIQA, Group of Environmental and Chemical Engineering, ESCET, Rey Juan Carlos University, Tulipán St., Móstoles, Madrid, 28933, Spain", "LATEP, Polymer Technology Laboratory, Rey Juan Carlos University, Tulipán St., Móstoles, Madrid, 28933, Spain"]

High-density polyethylene (HDPE) is one of the most used and demanded plastic, not only for packaging, but also for construction and within this application especially for non-pressure and pressure pipes, which makes this material the most abundant in the municipal waste stream. On the basis of the Circular Economy and the sustainable life that promotes, it is important to explore new applications for recycled HDPE (rHDPE) to increase the polymer recycled uptake. However, recycled HDPE is not currently being used in pressure pipes, mainly due to the high structural and loading requirements that must be met. The present study evaluates the potential use of post-consumer rHDPE from different origins in the manufacture of polyethylene pressure pipes. Different rHDPE sources are blended in different ratios with raw HDPE with PE100 grade quality. Blends are fully characterized to determine their feasibility to be used for pipe applications. Properties such as tensile strength at yield, elongation at break and flexural modulus for all blends yield values above the minimum required for PE100 grades. Furthermore, two important mechanical properties of polyethylene pipes, Slow Crack Growth (SCG) and Rapid Crack Propagation (RCP) resistances, are deeply evaluated. Remarkably, a dual correlation of SCG and RCP with the content of recycled PE in blends was established, allowing to develop predictive capabilities that guarantee the requirements and specifications for pressure pipe applications. Finally, through the evaluation of different waste streams, it can be concluded that handling, sorting, separation and selection of polyethylene's waste is critical to achieve the required pipe specifications, and to increase the percentage of post-consumer rHDPE into the final product. This investigation is in line with the sustainability objective and the commitment to boost the circular economy by replacing part of the conventional HDPE raw material with recycled HDPE to increase close-loop recycling on PE for pipe application, and the basis for the recycling of rHDPE from pipe at its end-life, after 50 years in service. © 2020 Elsevier Ltd

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Green energy: Hydroprocessing waste polypropylene to produce transport fuel

Journal of Cleaner Production

Mangesh, V.L. and Tamizhdurai, P. and Santhana Krishnan, P. and Narayanan, S. and Umasankar, S. and Padmanabhan, S. and Shanthi, K.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85091262310&doi=10.1016%2fj.jclepro.2020.124200&partnerID=40&md5=0f38194e381334a9b442753c39e44775

["Sathyabama Institute of Science and Technology, Jeppiar Nagar, Chennai, 600119, India", "Environmental and Water Resources Engineering Division, Department of Civil Engineering, Indian Institute of Technology Madras, Chennai, 600036, India", "Department of Chemistry, Anna University, Chennai, 600025, India", "Sriram College of Arts and Science, Perumalpattu, Tiruvallur, Tamilnadu 602024, India", "Department of Automobile Engineering, Vel Tech Rangarajan Dr Sagunthala R&D Institute of Science and Technology, Avadi, Chennai, 600062, India"]

The research aims to produce a viable transport fuel from post-consumer polypropylene plastic. The post-consumer plastic pollution mitigation efforts have found solutions through the circular economy

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High elasticity, chemically recyclable, thermoplastics from bio-based monomers: Carbon dioxide, limonene oxide and ε-decalactone†

Green Chemistry

Carrodeguas, L.P. and Chen, T.T.D. and Gregory, G.L. and Sulley, G.S. and Williams, C.K.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85098124413&doi=10.1039%2fd0gc02295k&partnerID=40&md5=a354612dc7285e90921ad53dd7fc76d0

Chemistry Research Lab, Department of Chemistry, 12 Mansfield Road, Oxford, OX1 3TA, United Kingdom

One solution to problems with petroleum derived plastics is to design polymers for the circular economy. In this regard, polymer chemistries, like ester or carbonate linkages, which are closer to equilibrium are very promising but to use these materials requires improvements to their properties and methods of manufacture. Here, efficient polymerization catalyses are used to transform wastes and bio-sourced monomers into thermoplastics which combine high elasticity and strength and which can be degraded to allow for some chemical recycling. The plastics are prepared from carbon dioxide, limonene oxide (from waste citrus fruit peel) and ϵ-decalactone (from triglycerides). These monomers are polymerized, using catalyzed controlled polymerizations with high conversion efficiencies, to selectively form ABA block polymers (A = high Tg polycarbonate, B = low Tg polyester). The series of 5 poly(limonene carbonate)-b-poly(ϵ-decalactone)-b-poly(limonene carbonate) (PLC-PDL-PLC) samples allow for systematic variations in the overall molar masses (Mn = 50-100 kg mol-1) and hard-block compositions (21-63 wt% PLC). All the polymers are fully characterized using a range of spectroscopies, gel permeation chromatography, thermal and tensile mechanical measurements. The leading plastic combines tensile strength (stress at break, σb = 21.2 MPa, Young's Modulus, Ey = 321 MPa) and high elasticity (elongation at break, ϵb = 400%)-an enhancement of more than 20× in elongation at break and tensile toughness over poly(limonene carbonate), overcoming the well-known brittleness and processing limitations of PLC. It undergoes selective, catalyzed depolymerization to limonene oxide, carbon dioxide and the precursor polyester providing a future chemical recycling and upcycling opportunity. This journal is © The Royal Society of Chemistry.

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Plastic bottle cap recycling-characterization of recyclate composition and opportunities for design for circularity

Sustainability

Gall, M. and Schweighuber, A. and Buchberger, W. and Lang, R.W.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85097554669&doi=10.3390%2fsu122410378&partnerID=40&md5=bbc0ad6eb1cd8b3520f031b3018f4995

["Institute of Polymeric Materials and Testing, Johannes Kepler University Linz, Altenberger Strasse 69, Linz, 4040, Austria", "Institute for Analytical Chemistry, Johannes Kepler University Linz, Altenberger Strasse 69, Linz, 4040, Austria"]

In line with efforts to create a circular economy of plastics, recent EU legislation is strengthening plastic bottle recycling by ambitious separate collection targets and mandatory recycled content obligations. Furthermore, explicit design requirements on the caps of bottles and composite beverage packaging have been introduced. These caps are typically made of polyethylene or polypropylene and often contain additives such as slip agents and anti-statics. Commercially available bottle cap recyclates (BCRs) as well as specifically formulated model compounds were analyzed in terms of composition by means of infrared spectroscopy, differential scanning calorimetry, and high-performance liquid chromatography. Their composition was found to be heterogeneous due to polyolefin cross-contamination, directly reflecting the diversity of cap materials present in the market. Slip agent legacy additives originating from the initial use phase were found and quantified in both commercial and model cap recyclates. This highlights the opportunity for redesigning plastic bottle caps not only in response to regulatory requirements, but to pursue a more comprehensive strategy of product design for circularity. By including considerations of polymer resin and additive choice in cap manufacturing, more homogeneous waste streams could be derived from plastic bottle cap recycling, enabling recycling into more demanding and valuable applications. © 2020 by the authors. Licensee MDPI, Basel, Switzerland.

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Implementation of life cycle based tools in the circular economy context—case study of plastic waste

Sustainability

Joachimiak-Lechman, K. and Garstecki, D. and Konopczynskiski, M. and Lewandowska, A.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85096824678&doi=10.3390%2fsu12239938&partnerID=40&md5=9208d496fa12da4f9353caefceb1de6a

["Department of Quality Management, Poznań University of Economics and Business, Poznan, 61-875, Poland", "Department of Management Accounting, Poznań University of Economics and Business, Poznan, 61-875, Poland", "AM Trans Progres Sp. z o.o., Suchy Las, 62-002, Poland"]

This article describes research done within the CIRCE2020 project, implemented under the INTERREG CENTRAL EUROPE 2014–2020 Programme. The main aim is to present the results of a life cycle assessment (LCA) and life cycle costing (LCC) carried out for a recycling plant in Wielkopolska. From the LCA perspective, the analyzed recycling plant performs two functions

rayyan-671784432

Circular economy: Comparative life cycle assessment of fossil polyethylene terephthalate (PET) and its recycled and bio-based counterparts

Management and Production Engineering Review

Rybaczewska-Blazejowska, M. and Mena-Nieto, A.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85100179907&doi=10.24425%2fmper.2020.136126&partnerID=40&md5=80a8022ebcb1d0aa67aeb9a27d9fbe4f

["Kielce University of Technology, Department of Production Engineering, Poland", "University of Huelva, School of Engineering, Department of Electrical and Thermal Engineering, Design and Projects Campus El Carmen, Huelva, 21007, Spain"]

The transition to circular economy requires diversifying material sources, improving secondary raw materials management, including recycling, and finally finding sustainable alternative materials. Both recycled and bio-based plastics are often regarded as promising alternatives to conventional fossil-based plastics. Their broad application instead of fossilbased plastics is, however, frequently the subject of criticism because of offering limited environmental benefits. The study presents a comparative life cycle assessment (LCA) of fossil-based polyethylene terephthalate (PET) versus its recycled and bio-based counterparts. The system boundary covers the plastics manufacturing and end-of-life plastic management stages (cradle-to-cradle/grave variant). Based on the data and assumptions set out in the research, recycled PET (rPET) demonstrates the best environmental profile out of the evaluated plastics in all impact categories. The study contributes to circular economy in plastics by providing transparent and consistent knowledge on their environmental portfolio. © 2020 Polish Academy of Sciences. All rights reserved.

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Chemical recycling of plastic waste: Bitumen, solvents, and polystyrene from pyrolysis oil

Waste Management

Baena-González, J. and Santamaria-Echart, A. and Aguirre, J.L. and González, S.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85090145035&doi=10.1016%2fj.wasman.2020.08.035&partnerID=40&md5=97fa3336a1a0b55264b9c945663807d8

["Cátedra de Medio Ambiente, Facultad de Ciencias, Universidad de Alcalá, Alcalá de Henares, Madrid 28871, Spain", "Environment and Bioproducts Group, Facultad de Ciencias, Universidad de Alcalá, Alcalá de Henares, Madrid 28871, Spain", "Centro de Química Aplicada y Biotecnología, Universidad de Alcalá, Alcalá de Henares, Madrid 28871, Spain"]

As an alternative to conventional plastic-waste treatments, herein, we report a pyrolytic plastic-recovery process in which diverse compounds and materials are recovered from the pyrolysis oil obtained from the plastic waste. Distillation of the pyrolysis oil led to a bitumen and a distilled fraction. The composition of the bitumen, as determined by saturate, aromatic, resin, and asphaltene (S.A.R.A.) analysis and corroborated by Fourier-transform infrared (FTIR) spectroscopy, was found to principally contain aromatics (55.05 wt%) and saturates (33.41 wt%), and has great potential as a modifier for bitumen mixtures by decreasing the viscosities or softening points of final products. The distilled fraction was characterised and compared to pyrolysis oil in terms of its physicochemical properties and composition. Analysis by gas-chromatography/mass-spectrometry (GC-MS) revealed high levels of aromatics, namely styrene, benzene, toluene, ethylbenzene, and α-methylstyrene, which are potentially recoverable base compounds for industrial use. With this in mind, the distillate was subjected to various processes, including aromatic extraction with sulfolane and subsequent fractional distillation to recover the principal compounds in the various GC-MS fractions. Fraction 1 was found to be rich in ethylbenzene and toluene, while fraction 2 contained 73.26 wt% styrene and was used to synthesise recycled polystyrene (PS), whose yield and molecular weight (Mw) were optimised by adjusting the initiator concentration, temperature, and time. The optimised recycled PS was characterised to provide a yield of 77.64% and a Mw higher than 53,000 g/mol

rayyan-671784435

Environmental life cycle assessment of the recycling processes of waste plastics recovered by landfill mining

Waste Management

Cappucci, G.M. and Avolio, R. and Carfagna, C. and Cocca, M. and Gentile, G. and Scarpellini, S. and Spina, F. and Tealdo, G. and Errico, M.E. and Ferrari, A.M.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85090041435&doi=10.1016%2fj.wasman.2020.07.048&partnerID=40&md5=39939b44e594ffc96bf323acb4bc8407

["Department of Sciences and Methods for Engineering, University of Modena and Reggio Emilia, Reggio Emilia, Piazzale Europa 1, Reggio Emilia, 42122, Italy", "EN&TECH, Interdepartmental Research Centre for Industrial Research and Technology Transfer in the field of Integrated Technologies for Sustainable Research, Efficient Energy Conversion, Building Energy Efficiency, Lighting and Home Automation, Reggio Emilia, Piazzale Europa 142122, Italy", "Institute for Polymers, Composites and Biomaterials, National Research Council of Italy(IPCB-CNR), via Campi Flegrei 34, Pozzuoli, 80078, Italy", "IREOS S.p.A., via Stefano Turr 165, Genova, 16147, Italy"]

Enhanced Landfill Mining (ELFM) is a powerful tool for the sustainable management of landfill sites, aiming at both land reclamation and material recovery/reuse. To enhance the recovery and recycling rate of excavated plastic fractions, in most cases destined to energy recovery, new convenient, effective and sustainable strategies are needed. In this study, a recovery and valorization process of ELFM excavated plastics has been validated through an integrated experimental and Life Cycle Assessment (LCA) approach, demonstrating the environmental sustainability of the secondary raw material generated, in terms of use of resources and emissions generated. In particular, the secondary granulate from ELFM was compared with a virgin product and the last one resulted to have a higher impact (more than 4.46 times greater than the first one), in particular for the use of the resource crude oil as raw material in the production of primary LDPE. The valorization process of the excavated plastic made the mechanical properties of the secondary raw material comparable to that of a primary material. © 2020

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Life Cycle Assessment of Compostable Coffee Pods: A US University Based Case Study

Scientific Reports -NATURE

Kooduvalli, K. and Vaidya, U.K. and Ozcan, S.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85086169619&doi=10.1038%2fs41598-020-65058-1&partnerID=40&md5=9bd3c9bc2daa489a09301d665e9e919b

["Fibers and Composites Manufacturing Facility, The University of Tennessee, 1321 White Avenue, Knoxville, TN 37996, United States", "Energy and Transportation Science Division, Oak Ridge National Laboratory, 2360 Cherahala Boulevard NTRC- 3, Knoxville, TN 37932, United States", "Institute for Advanced Composites Manufacturing Innovation, 2360 Cherahala Boulevard, Knoxville, TN 37932, United States"]

Single-serve machines have proven to be a rapid and convenient mechanism for preparing coffee for consumption. However, disposing the single-use coffee pods accompanying each use creates insurmountable waste in landfills. With the introduction of biobased products being certified as industrially compostable, there is scope for an effective waste stream for nearly all biobased products that avoids adding to landfills. The case presented in this paper demonstrates the success of composting compostable coffee pods within a local industrial-scale composting facility. Utilizing the existing local composting facility at the University of Tennessee–Knoxville, a life cycle assessment was performed to calculate the overall embodied energy and related environmental impact(s) to determine the feasibility of using compostable coffee pods over conventional plastic ones. Testing showed complete degradation within 46 days, proving composting to be a feasible waste stream option and a sustainable marketing edge while treading the path toward a circular economy. Cost savings of 21% were realized in terms of waste disposal, in addition to creating a value-added product at the end of the coffee pods life cycle, with nutrient-rich compost being recirculated to campus gardens and farms. © 2020, The Author(s).

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A closed-loop process design for recycling expanded polystyrene waste by dissolution and polymerization

Mumbach, G.D. and Bolzan, A. and Machado, R.A.F.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85090232576&doi=10.1016%2fj.polymer.2020.122940&partnerID=40&md5=8218ea4f99fbce7a3ff5496f2c539530

Department of Chemical Engineering and Food Engineering, Federal University of Santa Catarina, UFSC, Campus Universitário, Centro Tecnológico, PO Box no 476 Florianópolis, Trindade, SC 88040-900, Brazil

This study investigated recycling of expanded polystyrene (EPS) waste in a closed-loop design using the dissolution technique. The objective is to dissolve a maximum rate of EPS waste in styrene (its monomer), followed by suspension polymerization of this solution to incorporate the monomer (the solvent) in the polymer chain to avoid the need to separate the polymer and the solvent. The study evaluated the best operating conditions for these procedures, which resulted in 92% g·g−1 of particles at the appropriate size for expansion (425–1400 μm). Fourier transform infrared spectroscopy (FTIR), gel permeation chromatography (GPC), dynamic mechanical analysis (DMA) and thermogravimetric analysis (TGA) were conducted to determine the chemical, thermal and rheological properties of the recycled polymers and to compare them with standard polymer, demonstrating that the recycled material kept its chemical, thermal, and rheological properties. This novel closed-loop technology has strong potential to produce recycled EPS with good properties and, if well established, will allow EPS recycling without the formation of secondary waste, in keeping with the principles of sustainable development and circular economy. A brief analysis of this process revealed a strong reduction in environmental impacts and suggests its economic viability, considering the demand for and market value of EPS and the investment required to produce it in a recycling process that could be amortized in a short period. © 2020 Elsevier Ltd

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Waste polypropylene plastic recycling toward climate change mitigation and circular economy: Energy, environmental, and technoeconomic perspectives

ACS Sustainable Chemistry and Engineering

Bora, R.R. and Wang, R. and You, F.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85096107410&doi=10.1021%2facssuschemeng.0c06311&partnerID=40&md5=9628130635f6b8d59a64bd7c303508a6

["Robert Frederick Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, NY 14853, United States", "College of Engineering, Cornell University, Ithaca, NY 14853, United States"]

Chemical recycling has the potential to reduce the environmental impacts from waste plastics, mitigate climate change, and contribute to circular economy. This study compares the environmental and economic performance of two such technologies, fast pyrolysis and gasification, with conventional disposal methods for treating polypropylene (PP) waste. High-fidelity process simulations for each technology are conducted to obtain the necessary mass, energy, and economic data for subsequent analyses. Through an extensive life cycle assessment utilizing the IPCC 2013, ReCiPe, and ILCD 2.0 methods, fast pyrolysis and gasification are determined to have lower overall greenhouse gas emissions and better overall environmental performance than the conventional methods of incineration and landfilling. The chemical recycling systems are also found to be considerably profitable with fast pyrolysis and gasification having total NPVs of $149MM and $96MM, respectively. The discount rate, waste PP price, and plant life are the most influential factors for the economic performance of both systems. © 2020 American Chemical Society.

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Danish plastic mass flows analysis

Sustainability

Vingwe, E. and Towa, E. and Remmen, A.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85096190373&doi=10.3390%2fsu12229639&partnerID=40&md5=dbe711eecac77e85a3cf8ba1f5c07122

["Department of planning and development, The Technical Faculty of IT and Design, Aalborg University, Aalborg, 9000, Denmark", "Institute for Environmental Management and Land-Use Planning, Université Libre de Bruxelles (ULB), Brussels, 1050, Belgium"]

In this paper, material flows and resource potentials for plastics at a national level in Denmark are mapped using an Environmentally Extended Multiregional Input-Output (EE-MRIO) database. EE-MRIO offers an operative improvement to current and prevalent methods for assessing the industrial and societal metabolism of resources, including plastics. The Exiobase is applied to map (1) the major sources, (2) calculate the total supply, (3) uses of plastics and waste generation, and (4) end of life pathways in order to indicate the potentials of plastics in the circular economy in Denmark with a focus on recycling. Furthermore, it elaborates how and why this method for performing Mass Flow Analysis (MFA) differs from mainstream assessments of material flows and from default uses of national statistical data. Overall, the results are that Denmark has a total supply of ≈551 kilotonnes (Kt) of plastics, out of which ≈522 Kt are used domestically and ≈168 Kt of plastic waste are generated annually. Out of the yearly amount of plastic waste, ≈50% is incinerated and 26% is recycled. These results indicate significant potentials for applying circular economy strategies and identify relevant sectors for closing the plastic loops. However, other initiatives are necessary, such as improvements in product design strategies, in the collection and sorting systems as well as in cross-sectoral collaboration. © 2020 by the authors. Licensee MDPI, Basel, Switzerland.

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Combining eco-design and LCA as decision-making process to prevent plastics in packaging application

Sustainability

Foschi, E. and Zanni, S. and Bonoli, A.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85096390636&doi=10.3390%2fsu12229738&partnerID=40&md5=c603001401b8e9d3e2e73b394e42f38a

["Department of Management, University of Bologna, Bologna, 40126, Italy", "Department of Civil, Chemical, Environmental and Materials Engineering, University of Bologna, Bologna, 40131, Italy"]

The diffusion of the culture of sustainability and circular economy increasingly pushes companies to adopt green strategies and integrate circular business models in the corporate agenda. It assumes higher relevance in the packaging industry because of the growing plastics demand, the increasing awareness of consumers on single-use-products, the low recyclability performance and last but not least, the challenge of urban littering and microplastics dispersion in marine ecosystem. This paper presents the case of a small-medium enterprise that implemented a decision-making process to rethink the design of frozen food packaging in accordance with systemic and life cycle thinking. Eco-design and Life Cycle Assessment (LCA) have been simultaneously used to test and validate the redesign process, thus fostering the substitution of the plastic “open and close� cap with a closing method entirely made of cardboard. Results shows how using an integrated decision-making system at the design stage have allowed to get up many benefits at multiple levels, including sustainable and safe supply chain, efficient logistic operations, better recyclability, and lower energy consumption. Moreover, even if it cannot be assessed by the existing tools, the solution provides a strong contribution to the reduction in the consumption of plastics and the prevention of marine pollution. © 2020 by the authors. Licensee MDPI, Basel, Switzerland.

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Towards a circular economy for plastic packaging wastes - the environmental potential of chemical recycling

Resources, Conservation and Recycling

Meys, R. and Frick, F. and Westhues, S. and Sternberg, A. and Klankermayer, J. and Bardow, A.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85087972211&doi=10.1016%2fj.resconrec.2020.105010&partnerID=40&md5=e436359e6548768bcd953e254c028fdb

["Institute for Technical Thermodynamics, RWTH Aachen University, Schinkelstr. 8, Aachen, 52062, Germany", "Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, Worringerweg 1, Aachen, 52074, Germany", "HTP GmbH & Co. KG, Maria-Theresia Allee 35, Aachen, 52064, Germany", "Institute of Energy and Climate Research - Energy Systems Engineering (IEK-10), Forschungszentrum Jülich GmbH, Jülich, Germany", "Energy & Process Systems Engineering, ETH Zürich, Zürich 8092, Switzerland"]

Plastic packaging waste faces increasingly stringent sustainability targets such as recycling rates of 55% imposed by the European Commission. To realize the vision of a circular economy, chemical recycling is advocated as a large-scale avenue to decrease fossil resource depletion and greenhouse gas (GHG) emissions. In this work, we develop a theoretical model for chemical recycling technologies assuming ideal performance. The theoretical model allows us to compute the minimal environmental impacts for chemical recycling technologies and compare them to real-case benchmark waste treatments. Thereby, we robustly identify chemical recycling technologies that will not result in environmental benefits, since their minimal environmental impacts are already higher than those of current benchmark waste treatments. In this way, we show that PET, HDPE, LDPE, PP and PS should not be recycled chemically to refinery feedstock or fuel products and rather be treated by mechanical recycling and energy recovery in cement kilns in order to reduce global warming impacts. In contrast, chemical recycling to monomers or value-added products could potentially reduce global warming impacts compared to all benchmark waste treatments by up to 4.3 kg CO2-eq per kg treated PET packaging waste. By analyzing 75 waste treatment scenarios for 5 environmental impacts, our analysis offers guidance to stakeholders involved in chemical recycling to identify the most promising as well as the least promising chemical recycling technologies. © 2020 The Authors

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Pyrolysis of plastic waste: Opportunities and challenges

Journal of Analytical and Applied Pyrolysis

Qureshi, M.S. and Oasmaa, A. and Pihkola, H. and Deviatkin, I. and Tenhunen, A. and Mannila, J. and Minkkinen, H. and Pohjakallio, M. and Laine-Ylijoki, J.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85084482179&doi=10.1016%2fj.jaap.2020.104804&partnerID=40&md5=adc23473b71358923e7b4d49c6a923a6

["VTT- Technical Research Centre of Finland, Tietotie 4C, Espoo, Finland", "Department of Sustainability Science, School of Energy Systems, Lappeenranta-Lahti University of Technology LUT, Lappeenranta, 53850, Finland", "Sulapac Ltd, Iso Roobertinkatu 21, Helsinki, 00120, Finland", "FCG Finnish Consulting Group Ltd., Osmontie 34, PL 950, Helsinki, 00601, Finland"]

With current low recycling rates and exponentially increasing production of plastics there is an increase in plastic material wastage, and thus new technologies are needed for waste refining. Presently in Europe, only about 10% of plastic waste is recycled, most of which is achieved through mechanical recycling. Chemical recycling methods like pyrolysis could significantly increase these recycling rates, as it can utilize mixtures of waste plastics unlike mechanical recycling. It can also be used to treat waste of many novel materials, such as composites, especially in the emerging phase when the volumes of the new materials in markets are low making separate collection of waste not a cost-efficient option. Pyrolysis offers an environmentally sound alternative to incineration and inefficient landfilling. Currently, main challenges for pyrolysis of plastic waste are unavailability and inconsistent quality of feedstock, inefficient and hence costly sorting, non-existent markets citing lack for standardized products, and unclear regulations around plastic waste management. Possible solutions could include tight cooperation between feedstock providers and converters for securing steady quantity and quality of feedstock. Advanced pre-treatment would provide the basis for cost-effective recycling. The classification of pyrolysis liquid as a product instead of waste is needed, and the REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals) registration should be carried out to standardise the liquid oil as a product. In addition, sustainability impacts need to be clearly positive. © 2020 Elsevier B.V.

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Extended producer responsibility: How to unlock the environmental and economic potential of plastic packaging waste?

Resources, Conservation and Recycling

Andreasi Bassi, S. and Boldrin, A. and Faraca, G. and Astrup, T.F.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85087713540&doi=10.1016%2fj.resconrec.2020.105030&partnerID=40&md5=349ad9b5a68fb2b5a1dae0206d718631

["Department of Environmental Engineering, Technical University of Denmark, DK-2800 Kgs, Lyngby, Denmark", "European Commission, Joint Research Centre, Calle Inca Garcilaso 3, Seville, 41092, Spain"]

Several are the challenges related to plastic waste, spanning from littering, high collection costs, and low recycling rates. Extended producer responsibility (EPR) is considered a key initiative to tackle some of these issues. To evaluate EPR role and effectiveness, 40 management scenarios focused on plastic packaging waste generated by Italian households were investigated, and their environmental performance (via a consequential life cycle assessment) and the economic sustainability of their waste value chain (via a cost-benefit analysis for each stakeholder) were compared to the recycling targets. Overall, packaging waste management represented an environmental burden. Yet, environmental benefits can be achieved by maximizing the collection rate, while minimizing the impurities collected with the source-segregated plastic and the processing losses in the recycling chain. Furthermore, the cost-benefit analysis showed that the recyclers are the weakest link in the value chain, and recycling of soft plastic and mixed polyolefin is generally not profitable. This increases the risk of exporting low-quality materials outside Europe, where their fate is uncertain. Finally, the results demonstrate that improving plastic packaging recyclability and strengthening the market for secondary plastic is critical for reaching the European recycling targets of 55% in 2030. © 2020 Elsevier B.V.

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Elemental concentration and migratability in bioplastics derived from organic waste

Chemosphere

Astolfi, M.L. and Marconi, E. and Lorini, L. and Valentino, F. and Silva, F. and Ferreira, B.S. and Canepari, S. and Majone, M.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85087071963&doi=10.1016%2fj.chemosphere.2020.127472&partnerID=40&md5=761d2612c8e9b53a9f32eab6a9721568

["Department of Chemistry, Sapienza University, Piazzale Aldo Moro 5, Rome, 00185, Italy", "Department of Public Health and Infectious Diseases, Sapienza University, Piazzale Aldo Moro 5, Rome, 00185, Italy", "Department of Chemistry, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Caparica, 2829-516, Portugal", "Biotrend - Inovação e Engenharia em Biotecnologia, S.A., Biocant Park, Núcleo o4 Lote 2, Cantanhede, 3060-197, Portugal"]

In line with the Circular Economy approach, the production of polyhydroxyalkanoate (PHA) with organic waste as the feedstock may a biotechnological application to reduce waste and recover high-value materials. The potential contaminants that could transfer from bio-waste to a PHA include inorganic elements, such as heavy metals. Hence, the total content and migratability of certain elements were evaluated in several PHA samples produced from different origins and following different methods. The total content of certain elements in PHA ranged between 0.0001 (Be) and 49,500 mg kg−1 (Na). The concentrations of some alkaline (Na and K) and alkaline earth (Ca and Mg) metals were highest, which are of little environmental concern. The feedstock type and PHA stabilisation and extraction procedures affected the element contents. Several sets of experiments were conducted to evaluate the migration of elements from the PHA samples under different storage times, temperatures, and pH levels. The total contents of some heavy metals (As, Cd, Fe, Hg, Ni, Pb, and Zn) in PHA produced from fruit waste or crops (commercial PHA) were lower than those in the PHA samples produced from the mixture of the organic fraction of municipal waste and sludge from wastewater treatment. Both the PHA obtained by extraction from wet biomass (acid storage) with aqueous phase extraction reagents and commercial PHA were below the migration limits stipulated by the current Toy Safety Directive and by Commission Regulation (EU) October 2011 on plastic materials and articles intended to come into contact with food under frozen and refrigerated conditions. © 2020 Elsevier Ltd

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Sustainable tetra pak recycled cellulose / Poly(Butylene succinate) based woody-like composites for a circular economy

Journal of Cleaner Production

Platnieks, O. and Barkane, A. and Ijudina, N. and Gaidukova, G. and Thakur, V.K. and Gaidukovs, S.

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85086304812&doi=10.1016%2fj.jclepro.2020.122321&partnerID=40&md5=5bc8804d3eccb4bf92af1f8a46db6f1f

["Faculty of Materials Science and Applied Chemistry, Institute of Polymer Materials, Riga Technical University, Riga, Latvia", "Biorefining and Advanced Materials Research Centre, Scotland's Rural College (SRUC), Kings Buildings, West Mains Road, Edinburgh, EH9 3JG, United Kingdom"]

Long term sustainability requires the elimination of waste products and their integration in the circular economy according to goals set by the European Union. Such is the case with Tetra pak one of the most extensively used food packaging materials in the world. More than half of the Tetra pak packaging ends up in the landfills due to the complicated disposal that requires special processing plants. The objective of this study is to investigate recycled cellulose (rCell) that has been separated from polypropylene and aluminum in the industrial processing plant as a structural filler for functional biocomposites. Cellulose-based waste products are widely used as filler materials for the composites classified as wood-plastic composites (WPC) and are one of the leading materials for sustainable building materials, furniture and packaging industry. We have selected one of the most promising bio-based and biodegradable polymers poly(butylene succinate) (PBS) that has comparable mechanical properties to polyethylene and polypropylene as a matrix for the composites. Thus, we propose a novel application route for rCell obtained during Tetra pak recycling process and evaluate its performance. High filler loading from 10 to 50 wt% has been used in the melt blending process to prepare 5 compositions that contain 55–75% bio-based carbon content. Life cycle inventory has been combined with excessive thermal and mechanical analysis to access the suitability of the composite for various application including submerging in water. The addition of 50 wt % of rCell into PBS leads to improvement of the hardness of the composites. Further, the rCell composites were found to have much higher Young's modulus compared to pristine PBS. The dynamic mechanical analysis showed that the storage modulus and the loss modulus were significantly enhanced in measured temperature range between −70 and 70 °C. The PBS/rCell composites were biodegradable in soil under composting conditions. Scanning electron microscopy analysis of fractured composites’ surfaces testifies the filler agglomeration process in the PBS/rCell composites and generation of voids, but the FTIR measurements indicate the generation of hydrogen bonding between the polymer and cellulose components. TGA evidence the increase in thermal stability of the rCell after incorporation in the PBS/rCell composites. © 2020 Elsevier Ltd