1
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Gil-Castell O, Jiménez-Robles R, Gálvez-Subiela A, Marco-Velasco G, Cumplido MP, Martín-Pérez L, Cháfer A, Badia JD. Factorial Analysis and Thermal Kinetics of Chemical Recycling of Poly(ethylene terephthalate) Aided by Neoteric Imidazolium-Based Ionic Liquids. Polymers (Basel) 2024; 16:2451. [PMID: 39274083 PMCID: PMC11397852 DOI: 10.3390/polym16172451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2024] [Revised: 08/05/2024] [Accepted: 08/21/2024] [Indexed: 09/16/2024] Open
Abstract
Poly(ethylene terephthalate) (PET) waste accumulation poses significant environmental challenges due to its persistent nature and current management limitations. This study explores the effectiveness of imidazolium-based neoteric solvents [Emim][OAc] and [Bmim][OAc] as catalytic co-solvents in the glycolysis of PET with ethylene glycol (EG). Reaction thermal kinetics showed that both ionic liquids (ILs) significantly enhanced the depolymerization rate of PET compared to traditional methods. The use of [Emim][OAc] offered a lower activation energy of 88.69 kJ·mol-1, thus making the process more energy-efficient. The contribution of key process parameters, including temperature (T), plastic-to-ionic liquid (P/IL) mass ratio, and plastic-to-solvent (P/S) mass ratio, were evaluated by means of a factorial analysis and optimized to achieve the maximum PET conversion for both neoteric solvents. The relevance sequence for both ionic liquids involved the linear factors T and P/S, followed by the interaction factors T×P/S and T×P/IL, with P/IL being the less significant parameter. The optimal conditions, with a predicted conversion of 100%, involved a temperature of 190 °C, with a P/IL of 1:1 and a P/S of 1:2.5, regardless of the IL used as the catalytic co-solvent.
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Affiliation(s)
- Oscar Gil-Castell
- Research Group in Materials Technology and Sustainability (MATS), Department of Chemical Engineering, School of Engineering, Universitat de València, Av. Universitat s/n, 46100 Burjassot, Valencia, Spain
| | - Ramón Jiménez-Robles
- Research Group in Materials Technology and Sustainability (MATS), Department of Chemical Engineering, School of Engineering, Universitat de València, Av. Universitat s/n, 46100 Burjassot, Valencia, Spain
| | - Alejandro Gálvez-Subiela
- Research Group in Materials Technology and Sustainability (MATS), Department of Chemical Engineering, School of Engineering, Universitat de València, Av. Universitat s/n, 46100 Burjassot, Valencia, Spain
| | - Gorka Marco-Velasco
- Research Group in Materials Technology and Sustainability (MATS), Department of Chemical Engineering, School of Engineering, Universitat de València, Av. Universitat s/n, 46100 Burjassot, Valencia, Spain
| | - M Pilar Cumplido
- Plastic Technology Centre (AIMPLAS), Gustave Eiffel 4, 46980 Paterna, Valencia, Spain
| | - Laia Martín-Pérez
- Research Group in Materials Technology and Sustainability (MATS), Department of Chemical Engineering, School of Engineering, Universitat de València, Av. Universitat s/n, 46100 Burjassot, Valencia, Spain
| | - Amparo Cháfer
- Research Group in Materials Technology and Sustainability (MATS), Department of Chemical Engineering, School of Engineering, Universitat de València, Av. Universitat s/n, 46100 Burjassot, Valencia, Spain
| | - Jose D Badia
- Research Group in Materials Technology and Sustainability (MATS), Department of Chemical Engineering, School of Engineering, Universitat de València, Av. Universitat s/n, 46100 Burjassot, Valencia, Spain
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2
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Okonye LU, Ren J. A comprehensive review of PETW recycling for supercapacitor applications. Heliyon 2024; 10:e35285. [PMID: 39170277 PMCID: PMC11336431 DOI: 10.1016/j.heliyon.2024.e35285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2024] [Revised: 07/24/2024] [Accepted: 07/25/2024] [Indexed: 08/23/2024] Open
Abstract
The rising measure of waste produced from polyethene terephthalate (PET) and the interest in eco-accommodating energy storage arrangements have prompted escalated examination into reusing waste PET into supercapacitors. This review aims to provide a comprehensive overview of the most recent advancements in the recycling of polyethylene terephthalate waste (PETW), as a supercapacitor electrode precursor. The review looks at different methodologies for recovering PET from waste, including mechanical, chemical, enzyme, etc. It further explores the combination strategies for electrode materials produced using PET. Besides, PET-derived materials' electrochemical performance in supercapacitor application is likewise broken down, with an emphasis on key electrochemical boundaries like capacitive behaviour, cyclic stability, and electrochemical impedance spectroscopy. The need for scalable and cost-effective recycling methods, the creation of eco-friendly electrolytes, and the improvement of the electrochemical performance of recycled PET-based supercapacitors are just a few of the issues and opportunities highlighted in this expanding eco-friendly industry. Overall, the goal of this review is to provide a comprehensive understanding of the cutting-edge developments in the use of recycled PETW as a precursor for supercapacitor electrodes, highlighting the eco-friendly energy storage solution's potential and contributing to a sustainable future.
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Affiliation(s)
- Leonard U. Okonye
- Department of Mechanical Engineering Science, University of Johannesburg, Cnr Kingsway and University Roads, Auckland Park, 2092, Johannesburg, South Africa
| | - Jianwei Ren
- Department of Chemical Engineering, University of Pretoria, Cnr Lynwood Road and Roper Street, Hatfield, 0028, South Africa
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3
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Arunphacharawit A, Poonsawat T, Meechai T, Chaicharoenwimolkul Chuaitammakit L, Somsook E. DFT study on the depolymerization of PET by Ca-catalyzed glycolysis reaction model. Heliyon 2024; 10:e34666. [PMID: 39145025 PMCID: PMC11320157 DOI: 10.1016/j.heliyon.2024.e34666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Revised: 06/28/2024] [Accepted: 07/15/2024] [Indexed: 08/16/2024] Open
Abstract
Poly(ethylene terephthalate) (PET) is the most common plastics produced for applications in food and drinking containers. It is degraded to valuable product by several methods. Glycolysis of PET gains bis(2-hydroxyethylene) terephthalate (BHET) as the main product utilized as plasticizer. Calcium catalysts, Ca2+ and Ca(OH)2∙2H2O were explored to study the mechanism of PET cleavage by DFT calculations at B3LYP/6-311++G** level. Two possible pathways, coordination, and non-coordination of ethylene glycol on the calcium in glycolysis reaction, have been investigated. In addition, poly(ethylene furanoate) (PEF), considered as a sustainable polymer with the similar functional properties, was chose for the comparison of conformational structures with PET. The understanding of the relationship between PET (and PEF) structures and calcium catalysts is useful for the future development of linear sustainable polyesters.
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Affiliation(s)
- Anyarin Arunphacharawit
- NANOCAST Laboratory, Center for Catalysis Science and Technology (CAST), Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Mahidol University, 272 Rama VI Road., Ratchathewi, Bangkok, 10400, Thailand
| | - Thinnaphat Poonsawat
- NANOCAST Laboratory, Center for Catalysis Science and Technology (CAST), Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Mahidol University, 272 Rama VI Road., Ratchathewi, Bangkok, 10400, Thailand
| | - Titiya Meechai
- Department of Premedical Science, Faculty of Medicine, Bangkokthonburi University, Thawi Watthana, Bangkok, 10170, Thailand
| | - Laksamee Chaicharoenwimolkul Chuaitammakit
- Chemistry and Applied Chemistry, Faculty of Science and Technology, Suratthani Rajabhat University, 272 Moo 9, Surat-Nasan Road, Khuntale, Muang, Surat Thani, 84100, Thailand
| | - Ekasith Somsook
- NANOCAST Laboratory, Center for Catalysis Science and Technology (CAST), Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Mahidol University, 272 Rama VI Road., Ratchathewi, Bangkok, 10400, Thailand
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4
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Ren T, Zhan H, Xu H, Chen L, Shen W, Xu Y, Zhao D, Shao Y, Wang Y. Recycling and high-value utilization of polyethylene terephthalate wastes: A review. ENVIRONMENTAL RESEARCH 2024; 249:118428. [PMID: 38325788 DOI: 10.1016/j.envres.2024.118428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 01/31/2024] [Accepted: 02/04/2024] [Indexed: 02/09/2024]
Abstract
Polyethelene terephthalate (PET) is a well-known thermoplastic, and recycling PET waste is important for the natural environment and human health. This study provides a comprehensive overview of the recycling and reuse of PET waste through energy recovery and physical, chemical, and biological recycling. This article summarizes the recycling methods and the high-value products derived from PET waste, specifically detailing the research progress on regenerated PET prepared by the mechanical recycling of fiber/yarn, fabric, and composite materials, and introduces the application of PET nanofibers recycled by physical dissolution and electrospinning in fields such as filtration, adsorption, electronics, and antibacterial materials. This article explains the energy recovery of PET through thermal decomposition and comprehensively discusses various chemical recycling methods, including the reaction mechanisms, catalysts, conversion efficiencies, and reaction products, with a brief introduction to PET biodegradation using hydrolytic enzymes provided. The analysis and comparison of various recycling methods indicated that the mechanical recycling method yielded PET products with a wide range of applications in composite materials. Electrospinning is a highly promising recycling strategy for fabricating recycled PET nanofibers. Compared to other methods, physical recycling has advantages such as low cost, low energy consumption, high value, simple processing, and environmental friendliness, making it the preferred choice for the recycling and high-value utilization of waste PET.
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Affiliation(s)
- Tianxiang Ren
- Key Laboratory of Clean Dyeing and Finishing Technology of Zhejiang Province, Zhejiang Sub-center of National Carbon Fiber Engineering Technology Research Center, Shaoxing Sub-center of National Engineering Research Center for Fiber-based Composites, Shaoxing Key Laboratory of High Performance fibers & products, College of Textile and Garment, Shaoxing University, Shaoxing, 312000, China
| | - Haihua Zhan
- Key Laboratory of Clean Dyeing and Finishing Technology of Zhejiang Province, Zhejiang Sub-center of National Carbon Fiber Engineering Technology Research Center, Shaoxing Sub-center of National Engineering Research Center for Fiber-based Composites, Shaoxing Key Laboratory of High Performance fibers & products, College of Textile and Garment, Shaoxing University, Shaoxing, 312000, China
| | - Huaizhong Xu
- Department of Biobased Materials Science, Kyoto Institute of Technology, Matsugasaki, Sakyo-Ku, Kyoto, 606-8585, Japan
| | - Lifeng Chen
- Shaoxing Baojing Composite Materials Co., Ltd., Shaoxing, 312000, China
| | - Wei Shen
- Shaoxing Baojing Composite Materials Co., Ltd., Shaoxing, 312000, China
| | - Yudong Xu
- Zhejiang Provincial Innovation Center of Advanced Textile Technology, Shaoxing, 312000, China
| | - Defang Zhao
- Key Laboratory of Clean Dyeing and Finishing Technology of Zhejiang Province, Zhejiang Sub-center of National Carbon Fiber Engineering Technology Research Center, Shaoxing Sub-center of National Engineering Research Center for Fiber-based Composites, Shaoxing Key Laboratory of High Performance fibers & products, College of Textile and Garment, Shaoxing University, Shaoxing, 312000, China; School of Materials Science and Engineering, Zhejiang University, Hangzhou, 310058, China; Hailiang Group Co., Ltd., Hangzhou, 310000, China.
| | - Yuanyi Shao
- College of Textiles, Donghua University, Shanghai, 201620, China.
| | - Yongtao Wang
- School of Medicine, Shanghai University, Shanghai, 200444, China.
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5
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Shi C, Quinn EC, Diment WT, Chen EYX. Recyclable and (Bio)degradable Polyesters in a Circular Plastics Economy. Chem Rev 2024; 124:4393-4478. [PMID: 38518259 DOI: 10.1021/acs.chemrev.3c00848] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/24/2024]
Abstract
Polyesters carrying polar main-chain ester linkages exhibit distinct material properties for diverse applications and thus play an important role in today's plastics economy. It is anticipated that they will play an even greater role in tomorrow's circular plastics economy that focuses on sustainability, thanks to the abundant availability of their biosourced building blocks and the presence of the main-chain ester bonds that can be chemically or biologically cleaved on demand by multiple methods and thus bring about more desired end-of-life plastic waste management options. Because of this potential and promise, there have been intense research activities directed at addressing recycling, upcycling or biodegradation of existing legacy polyesters, designing their biorenewable alternatives, and redesigning future polyesters with intrinsic chemical recyclability and tailored performance that can rival today's commodity plastics that are either petroleum based and/or hard to recycle. This review captures these exciting recent developments and outlines future challenges and opportunities. Case studies on the legacy polyesters, poly(lactic acid), poly(3-hydroxyalkanoate)s, poly(ethylene terephthalate), poly(butylene succinate), and poly(butylene-adipate terephthalate), are presented, and emerging chemically recyclable polyesters are comprehensively reviewed.
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Affiliation(s)
- Changxia Shi
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Ethan C Quinn
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Wilfred T Diment
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Eugene Y-X Chen
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
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6
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Zhou K, Liu Q, Feng J, Chang T, Liu J. Comprehensive environmental performance of bottle-to-bottle recycling of PET bottles based on deposit-refund system in China. WASTE MANAGEMENT (NEW YORK, N.Y.) 2023; 172:90-100. [PMID: 37879269 DOI: 10.1016/j.wasman.2023.10.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Revised: 09/08/2023] [Accepted: 10/20/2023] [Indexed: 10/27/2023]
Abstract
Polyethylene terephthalate (PET) is a widely used packaging material and has high value in recycling. However, under China's dominant informal recycling system, most PET bottles are downcycled into fibers. The deposit-refund system (DRS) is considered a feasible mechanism to facilitate the high-value recycling of PET bottles. To comparatively evaluate the environmental performance [reduction of greenhouse gas (GHG) and pollutant emissions] under different scenarios using life cycle assessments, including the current system based on informal recycling, an improved system with a larger contribution from the source separation of municipal solid waste, and evolving systems with DRS application, five scenarios were set up. The DRS can reduce GHG emissions and the comprehensive environmental impact by 0.538 kg CO2 /kg PET bottles and 1.73 × 10-3 PE/kg PET bottles, respectively, compared to informal recycling. It can be concluded that the DRS-based recycling approach and the bottle-to-bottle recycling provide the substantial emission reduction potential of GHGs and pollutants.
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Affiliation(s)
- Keren Zhou
- School of Environment, Tsinghua University, Beijing 10084, China
| | - Qin Liu
- School of Environment, Tsinghua University, Beijing 10084, China
| | - Juan Feng
- Beijing INCOM Recycle Co., Ltd, Beijing 101312, China
| | - Tao Chang
- Beijing INCOM Recycle Co., Ltd, Beijing 101312, China
| | - Jianguo Liu
- School of Environment, Tsinghua University, Beijing 10084, China.
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7
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Fayon P, Devémy J, Emeriau-Viard C, Ballerat-Busserolles K, Goujon F, Dequidt A, Marty A, Hauret P, Malfreyt P. Energetic and Structural Characterizations of the PET-Water Interface as a Key Step in Understanding Its Depolymerization. J Phys Chem B 2023; 127:3543-3555. [PMID: 37018548 DOI: 10.1021/acs.jpcb.3c00600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2023]
Abstract
We report molecular simulations of the interaction between poly(ethylene terephthalate) (PET) surfaces and water molecules with a short-term goal to better evaluate the different energy contributions governing the enzymatic degradation of amorphous PET. After checking that the glass transition temperature, density, entanglement mass, and mechanical properties of an amorphous PET are well reproduced by our molecular model, we extend the study to the extraction of a monomer from the bulk surface in different environments, i.e., water, vacuum, dodecane, and ethylene glycol. We complete this energetic characterization by the calculation of the work of adhesion of PET surfaces with water and dodecane molecules and by the determination of the contact angle of water droplets. These calculations are compared with experiments and should help us to better understand the enzymatic degradation of PET from both the thermodynamic and molecular viewpoints.
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Affiliation(s)
- Pierre Fayon
- Université Clermont Auvergne, Clermont Auvergne INP, CNRS, Institut de Chimie de Clermont-Ferrand, F-63000 Clermont-Ferrand, France
| | - Julien Devémy
- Université Clermont Auvergne, Clermont Auvergne INP, CNRS, Institut de Chimie de Clermont-Ferrand, F-63000 Clermont-Ferrand, France
| | - Constance Emeriau-Viard
- Manufacture Française des Pneumatiques Michelin, 23, Place des Carmes, 63040 Clermont-Ferrand, France
| | - Karine Ballerat-Busserolles
- Université Clermont Auvergne, Clermont Auvergne INP, CNRS, Institut de Chimie de Clermont-Ferrand, F-63000 Clermont-Ferrand, France
| | - Florent Goujon
- Université Clermont Auvergne, Clermont Auvergne INP, CNRS, Institut de Chimie de Clermont-Ferrand, F-63000 Clermont-Ferrand, France
| | - Alain Dequidt
- Université Clermont Auvergne, Clermont Auvergne INP, CNRS, Institut de Chimie de Clermont-Ferrand, F-63000 Clermont-Ferrand, France
| | - Alain Marty
- Carbios, Parc Cataroux, Batiment B80, 8 rue de la Grolière, 63100 Clermont-Ferrand, France
| | - Patrice Hauret
- Manufacture Française des Pneumatiques Michelin, 23, Place des Carmes, 63040 Clermont-Ferrand, France
| | - Patrice Malfreyt
- Université Clermont Auvergne, Clermont Auvergne INP, CNRS, Institut de Chimie de Clermont-Ferrand, F-63000 Clermont-Ferrand, France
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8
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Kulkarni A, Quintens G, Pitet LM. Trends in Polyester Upcycling for Diversifying a Problematic Waste Stream. Macromolecules 2023. [DOI: 10.1021/acs.macromol.2c02054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/06/2023]
Affiliation(s)
- Amruta Kulkarni
- Advanced Functional Polymers (AFP) Laboratory, Institute for Materials Research (imo-imomec), Hasselt University, Martelarenlaan 42, 3500 Hasselt, Belgium
| | - Greg Quintens
- Advanced Functional Polymers (AFP) Laboratory, Institute for Materials Research (imo-imomec), Hasselt University, Martelarenlaan 42, 3500 Hasselt, Belgium
| | - Louis M. Pitet
- Advanced Functional Polymers (AFP) Laboratory, Institute for Materials Research (imo-imomec), Hasselt University, Martelarenlaan 42, 3500 Hasselt, Belgium
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9
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Dulal M, Afroj S, Ahn J, Cho Y, Carr C, Kim ID, Karim N. Toward Sustainable Wearable Electronic Textiles. ACS NANO 2022; 16:19755-19788. [PMID: 36449447 PMCID: PMC9798870 DOI: 10.1021/acsnano.2c07723] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Accepted: 11/10/2022] [Indexed: 06/06/2023]
Abstract
Smart wearable electronic textiles (e-textiles) that can detect and differentiate multiple stimuli, while also collecting and storing the diverse array of data signals using highly innovative, multifunctional, and intelligent garments, are of great value for personalized healthcare applications. However, material performance and sustainability, complicated and difficult e-textile fabrication methods, and their limited end-of-life processability are major challenges to wide adoption of e-textiles. In this review, we explore the potential for sustainable materials, manufacturing techniques, and their end-of-the-life processes for developing eco-friendly e-textiles. In addition, we survey the current state-of-the-art for sustainable fibers and electronic materials (i.e., conductors, semiconductors, and dielectrics) to serve as different components in wearable e-textiles and then provide an overview of environmentally friendly digital manufacturing techniques for such textiles which involve less or no water utilization, combined with a reduction in both material waste and energy consumption. Furthermore, standardized parameters for evaluating the sustainability of e-textiles are established, such as life cycle analysis, biodegradability, and recyclability. Finally, we discuss the current development trends, as well as the future research directions for wearable e-textiles which include an integrated product design approach based on the use of eco-friendly materials, the development of sustainable manufacturing processes, and an effective end-of-the-life strategy to manufacture next generation smart and sustainable wearable e-textiles that can be either recycled to value-added products or decomposed in the landfill without any negative environmental impacts.
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Affiliation(s)
- Marzia Dulal
- Centre
for Print Research (CFPR), University of
the West of England, Frenchay Campus, BristolBS16 1QY, United
Kingdom
| | - Shaila Afroj
- Centre
for Print Research (CFPR), University of
the West of England, Frenchay Campus, BristolBS16 1QY, United
Kingdom
| | - Jaewan Ahn
- Department
of Materials Science and Engineering, Korea
Advanced Institute of Science and Technology (KAIST), Daejeon34141, Republic of Korea
| | - Yujang Cho
- Department
of Materials Science and Engineering, Korea
Advanced Institute of Science and Technology (KAIST), Daejeon34141, Republic of Korea
| | - Chris Carr
- Clothworkers’
Centre for Textile Materials Innovation for Healthcare, School of
Design, University of Leeds, LeedsLS2 9JT, United Kingdom
| | - Il-Doo Kim
- Department
of Materials Science and Engineering, Korea
Advanced Institute of Science and Technology (KAIST), Daejeon34141, Republic of Korea
| | - Nazmul Karim
- Centre
for Print Research (CFPR), University of
the West of England, Frenchay Campus, BristolBS16 1QY, United
Kingdom
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10
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Gazzotti S, De Felice B, Ortenzi MA, Parolini M. Approaches for Management and Valorization of Non-Homogeneous, Non-Recyclable Plastic Waste. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:10088. [PMID: 36011719 PMCID: PMC9408078 DOI: 10.3390/ijerph191610088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 08/07/2022] [Accepted: 08/12/2022] [Indexed: 06/15/2023]
Abstract
The environmental accumulation of plastic wastes has become one of the most discussed topics in the scientific community. The development of new strategies to tackle this issue is of crucial importance, and different approaches are being investigated to effectively reduce plastic waste generated by improper or inefficient disposal. In addition to the efforts addressing the development of biodegradable plastics, the research is currently focused on the development of innovative recycling approaches. Indeed, although most plastic materials are potentially recyclable, only 15% of the worldwide plastic waste is currently recycled, while the remaining 85% is usually incinerated to recover thermal energy or landfilled. The hurdles to efficient recycling come from improper management of end-of-life plastic goods. Moreover, the highly heterogeneous nature and versatility of plastic and polymeric materials have led to the development of multilayered materials, composites, blends and many other different species, whose management and/or reprocessing to yield high-value products is extremely challenging. Thus, although these materials are extremely valuable from an industrial point of view, they add a high degree of complexity to the recycling process because each one of them is different from the other, but they cannot be separated efficiently. The aim of the present review is to return a comprehensive overview of environmental and management issues related to the complex and heterogeneous mixture of plastic waste that is generated at the end of the sorting procedures in Italian plastic recycling plants, the so-called 'Plasmix'. This review lists the difficulties and limitations related to the management of non-recyclable Plasmix and highlights the strategies for the proper, sustainable and valuable use of this plastic waste.
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Affiliation(s)
- Stefano Gazzotti
- Department of Environmental Science and Policy, University of Milan, Via Celoria 26, 20133 Milan, Italy
| | - Beatrice De Felice
- Department of Environmental Science and Policy, University of Milan, Via Celoria 26, 20133 Milan, Italy
| | - Marco Aldo Ortenzi
- Department of Chemistry, University of Milan, Via Golgi 19, 20133 Milan, Italy
| | - Marco Parolini
- Department of Environmental Science and Policy, University of Milan, Via Celoria 26, 20133 Milan, Italy
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11
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Seyedi M, Savchak M, Tiiara A, Luzinov I. Toward Mechanical Recycling of Polystyrene/Polypropylene Blends with Bottlebrush-Modified Graphene Oxide as a Compatibilizer. ACS APPLIED MATERIALS & INTERFACES 2022; 14:35074-35086. [PMID: 35876471 DOI: 10.1021/acsami.2c07459] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The compatibilization of immiscible polystyrene/polypropylene (PS/PP) blends with virgin graphene oxide (GO-V) and GO modified with a bottlebrush reactive copolymer layer (GO-P) is reported. This practically important blend was chosen since, currently, PS and PP are recycled to a very low degree. The amphiphilic bottlebrush copolymer synthesized by us contained hydrophobic and hydrophilic side chains and was attached to the GO nanosheets via epoxy functionality. The GO modification and the introduction of GO into the blend were conducted from water. Thus, the introduction of the compatibilizing nanomaterial can be conducted during the mechanical recycling washing stage in a real-world situation. The final blend was prepared via melt mixing using an extruder. We examined the influence of GO modification and the mixing order on the blends' morphology, rheology, and mechanical properties. Thermodynamic calculations predicted a higher interfacial activity of GO nanosheets in PS/PP/GO-P blends than that in PS/PP/GO-V blends. The morphological and rheological study assessed this prediction. It was demonstrated that the bottlebrush-modified GO-P sheets were readily driven to the PS/PP interphase. The mechanical measurements showed enhanced mechanical properties for PS/PP/GO-P blends, especially for those in which GO was first premixed with PS.
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Affiliation(s)
- Mastooreh Seyedi
- Department of Materials Science and Engineering, Clemson University, Clemson, South Carolina 29634, United States
| | - Mykhailo Savchak
- Department of Materials Science and Engineering, Clemson University, Clemson, South Carolina 29634, United States
| | - Andrii Tiiara
- Department of Materials Science and Engineering, Clemson University, Clemson, South Carolina 29634, United States
| | - Igor Luzinov
- Department of Materials Science and Engineering, Clemson University, Clemson, South Carolina 29634, United States
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12
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Schirmeister CG, Mülhaupt R. Closing the Carbon Loop in the Circular Plastics Economy. Macromol Rapid Commun 2022; 43:e2200247. [PMID: 35635841 DOI: 10.1002/marc.202200247] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 05/07/2022] [Indexed: 11/06/2022]
Abstract
Today, plastics are ubiquitous in everyday life, problem solvers of modern technologies, and crucial for sustainable development. Yet the surge in global demand for plastics of the growing world population has triggered a tidal wave of plastic debris in the environment. Moving from a linear to a zero-waste and carbon-neutral circular plastic economy is vital for the future of the planet. Taming the plastic waste flood requires closing the carbon loop through plastic reuse, mechanical and molecular recycling, carbon capture, and use of the greenhouse gas carbon dioxide. In the quest for eco-friendly products, plastics do not need to be reinvented but tuned for reuse and recycling. Their full potential must be exploited regarding energy, resource, and eco efficiency, waste prevention, circular economy, climate change mitigation, and lowering environmental pollution. Biodegradation holds promise for composting and bio-feedstock recovery, but it is neither the Holy Grail of circular plastics economy nor a panacea for plastic littering. As an alternative to mechanical downcycling, molecular recycling enables both closed-loop recovery of virgin plastics and open-loop valorization, producing hydrogen, fuels, refinery feeds, lubricants, chemicals, and carbonaceous materials. Closing the carbon loop does not create a Perpetuum Mobile and requires renewable energy to achieve sustainability. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Carl G Schirmeister
- Freiburg Materials Research Center and Institute for Macromolecular Chemistry, University of Freiburg, Stefan-Meier-Str. 31, D-79104, Freiburg, Germany
| | - Rolf Mülhaupt
- Sustainability Center, University of Freiburg, Ecker-Str. 4, D-79104, Freiburg, Germany
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14
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Yaroslavov AA, Panova IG, Arzhakov MS, Khokhlov AR. Interpolymer Complexes and Problem of Polymer Waste Management. RUSS J APPL CHEM+ 2022. [DOI: 10.1134/s1070427222040024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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15
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Verschoor JA, Kusumawardhani H, Ram AFJ, de Winde JH. Toward Microbial Recycling and Upcycling of Plastics: Prospects and Challenges. Front Microbiol 2022; 13:821629. [PMID: 35401461 PMCID: PMC8985596 DOI: 10.3389/fmicb.2022.821629] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Accepted: 02/15/2022] [Indexed: 12/12/2022] Open
Abstract
Annually, 400 Mt of plastics are produced of which roughly 40% is discarded within a year. Current plastic waste management approaches focus on applying physical, thermal, and chemical treatments of plastic polymers. However, these methods have severe limitations leading to the loss of valuable materials and resources. Another major drawback is the rapid accumulation of plastics into the environment causing one of the biggest environmental threats of the twenty-first century. Therefore, to complement current plastic management approaches novel routes toward plastic degradation and upcycling need to be developed. Enzymatic degradation and conversion of plastics present a promising approach toward sustainable recycling of plastics and plastics building blocks. However, the quest for novel enzymes that efficiently operate in cost-effective, large-scale plastics degradation poses many challenges. To date, a wide range of experimental set-ups has been reported, in many cases lacking a detailed investigation of microbial species exhibiting plastics degrading properties as well as of their corresponding plastics degrading enzymes. The apparent lack of consistent approaches compromises the necessary discovery of a wide range of novel enzymes. In this review, we discuss prospects and possibilities for efficient enzymatic degradation, recycling, and upcycling of plastics, in correlation with their wide diversity and broad utilization. Current methods for the identification and optimization of plastics degrading enzymes are compared and discussed. We present a framework for a standardized workflow, allowing transparent discovery and optimization of novel enzymes for efficient and sustainable plastics degradation in the future.
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Affiliation(s)
- Jo-Anne Verschoor
- Molecular Biotechnology, Institute of Biology, Leiden University, Leiden, Netherlands
| | | | - Arthur F. J. Ram
- Molecular Biotechnology, Institute of Biology, Leiden University, Leiden, Netherlands
| | - Johannes H. de Winde
- Molecular Biotechnology, Institute of Biology, Leiden University, Leiden, Netherlands
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16
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Affiliation(s)
- Dhananjay Dileep
- Chemical and Biological Engineering, Sweeney Hall, Iowa State University 618 Bissell Road Ames 50011 Iowa USA
| | - Michael Forrester
- Chemical and Biological Engineering, Sweeney Hall, Iowa State University 618 Bissell Road Ames 50011 Iowa USA
| | - Eric Cochran
- Chemical and Biological Engineering, Sweeney Hall, Iowa State University 618 Bissell Road Ames 50011 Iowa USA
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17
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Bascucci C, Duretek I, Lehner S, Holzer C, Gaan S, Hufenus R, Gooneie A. Investigating thermomechanical recycling of poly(ethylene terephthalate) containing phosphorus flame retardants. Polym Degrad Stab 2022. [DOI: 10.1016/j.polymdegradstab.2021.109783] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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18
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Attallah OA, Azeem M, Nikolaivits E, Topakas E, Fournet MB. Progressing Ultragreen, Energy-Efficient Biobased Depolymerization of Poly(ethylene terephthalate) via Microwave-Assisted Green Deep Eutectic Solvent and Enzymatic Treatment. Polymers (Basel) 2021; 14:polym14010109. [PMID: 35012131 PMCID: PMC8747168 DOI: 10.3390/polym14010109] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2021] [Revised: 12/21/2021] [Accepted: 12/24/2021] [Indexed: 11/16/2022] Open
Abstract
Effective interfacing of energy-efficient and biobased technologies presents an all-green route to achieving continuous circular production, utilization, and reproduction of plastics. Here, we show combined ultragreen chemical and biocatalytic depolymerization of polyethylene terephthalate (PET) using deep eutectic solvent (DES)-based low-energy microwave (MW) treatment followed by enzymatic hydrolysis. DESs are emerging as attractive sustainable catalysts due to their low toxicity, biodegradability, and unique biological compatibility. A green DES with triplet composition of choline chloride, glycerol, and urea was selected for PET depolymerization under MW irradiation without the use of additional depolymerization agents. Treatment conditions were studied using Box-Behnken design (BBD) with respect to MW irradiation time, MW power, and volume of DES. Under the optimized conditions of 20 mL DES volume, 260 W MW power, and 3 min MW time, a significant increase in the carbonyl index and PET percentage weight loss was observed. The combined MW-assisted DES depolymerization and enzymatic hydrolysis of the treated PET residue using LCC variant ICCG resulted in a total monomer conversion of ≈16% (w/w) in the form of terephthalic acid, mono-(2-hydroxyethyl) terephthalate, and bis-(2-hydroxyethyl) terephthalate. Such high monomer conversion in comparison to enzymatically hydrolyzed virgin PET (1.56% (w/w)) could be attributed to the recognized depolymerization effect of the selected DES MW treatment process. Hence, MW-assisted DES technology proved itself as an efficient process for boosting the biodepolymerization of PET in an ultrafast and eco-friendly manner.
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Affiliation(s)
- Olivia A. Attallah
- Materials Research Institute, Technological University of the Shannon: Midlands Midwest, N37 HD68 Athlone, Ireland; (O.A.A.); (M.B.F.)
- Pharmaceutical Chemistry Department, Faculty of Pharmacy, Heliopolis University, Cairo-Belbeis Desert Road, El Salam, Cairo 11777, Egypt
| | - Muhammad Azeem
- Materials Research Institute, Technological University of the Shannon: Midlands Midwest, N37 HD68 Athlone, Ireland; (O.A.A.); (M.B.F.)
- Correspondence:
| | - Efstratios Nikolaivits
- Biotechnology Laboratory, Industrial Biotechnology & Biocatalysis Group, School of Chemical Engineering, National Technical University of Athens, 15780 Athens, Greece; (E.N.); (E.T.)
| | - Evangelos Topakas
- Biotechnology Laboratory, Industrial Biotechnology & Biocatalysis Group, School of Chemical Engineering, National Technical University of Athens, 15780 Athens, Greece; (E.N.); (E.T.)
| | - Margaret Brennan Fournet
- Materials Research Institute, Technological University of the Shannon: Midlands Midwest, N37 HD68 Athlone, Ireland; (O.A.A.); (M.B.F.)
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19
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Thiyagarajan S, Maaskant-Reilink E, Ewing TA, Julsing MK, van Haveren J. Back-to-monomer recycling of polycondensation polymers: opportunities for chemicals and enzymes. RSC Adv 2021; 12:947-970. [PMID: 35425100 PMCID: PMC8978869 DOI: 10.1039/d1ra08217e] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 12/21/2021] [Indexed: 12/29/2022] Open
Abstract
The use of plastics in a wide range of applications has grown substantially over recent decades, resulting in enormous growth in production volumes to meet demand. Though a wide range of biomass-derived chemicals and materials are available on the market, the production volumes of such renewable alternatives are currently not sufficient to replace their fossil-based analogues due to various factors, in particular cost-effectiveness. Hence, the majority of plastics are still industrially produced from fossil-based feedstocks. Moreover, various reports have clearly raised concern about the plastics that are not recycled at their end-of-life and instead end up in landfills or the oceans. To avoid further pollution of our planet, it is highly desirable to develop recycling processes that use plastic waste as feedstock. Chemical recycling processes could potentially offer a solution, since they afford monomers from which new polymers can be produced, with the same performance as virgin plastics. In this manuscript, the opportunities for using either chemical or biochemical (i.e., enzymatic) approaches in the depolymerization of polycondensation polymers for recycling purposes are reviewed. Our aim is to highlight the strategies that have been developed so far to break down plastic waste into monomers, providing the first step in the development of chemical recycling processes for plastic waste, and to create a renewed awareness of the need to valorize plastic waste by efficiently transforming it into virgin plastics.
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Affiliation(s)
| | | | - Tom A Ewing
- Wageningen Food & Biobased Research Wageningen P. O. Box 17 6700 AA The Netherlands
| | - Mattijs K Julsing
- Wageningen Food & Biobased Research Wageningen P. O. Box 17 6700 AA The Netherlands
| | - Jacco van Haveren
- Wageningen Food & Biobased Research Wageningen P. O. Box 17 6700 AA The Netherlands
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20
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Biermann L, Quast D, Brepohl E, Eichert C, Scholl S. Alkali Depolymerization of Poly(ethylene terephthalate) in a Quasi‐solid‐solid Kneading Reaction. Chem Eng Technol 2021. [DOI: 10.1002/ceat.202100327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Lars Biermann
- Technische Universität Braunschweig Institute for Chemical and Thermal Process Engineering (ICTV) Langer Kamp 7 38106 Braunschweig Germany
- RITTEC Umwelttechnik GmbH Feldstrasse 29 21335 Lüneburg Germany
| | - David Quast
- Technische Universität Braunschweig Institute for Chemical and Thermal Process Engineering (ICTV) Langer Kamp 7 38106 Braunschweig Germany
| | - Esther Brepohl
- Technische Universität Braunschweig Institute for Chemical and Thermal Process Engineering (ICTV) Langer Kamp 7 38106 Braunschweig Germany
| | - Carsten Eichert
- RITTEC Umwelttechnik GmbH Feldstrasse 29 21335 Lüneburg Germany
| | - Stephan Scholl
- Technische Universität Braunschweig Institute for Chemical and Thermal Process Engineering (ICTV) Langer Kamp 7 38106 Braunschweig Germany
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21
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Sarda P, Hanan JC, Lawrence JG, Allahkarami M. Sustainability performance of polyethylene terephthalate, clarifying challenges and opportunities. JOURNAL OF POLYMER SCIENCE 2021. [DOI: 10.1002/pol.20210495] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Parikshit Sarda
- Polymer Institute, Department of Chemical Engineering University of Toledo Toledo Ohio USA
| | - Jay C. Hanan
- Mechanical and Aerospace Engineering Oklahoma State University Tulsa Oklahoma USA
| | - Joseph G. Lawrence
- Polymer Institute, Department of Chemical Engineering University of Toledo Toledo Ohio USA
| | - Masoud Allahkarami
- Mechanical and Aerospace Engineering Oklahoma State University Tulsa Oklahoma USA
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22
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Polyolefins and Polyethylene Terephthalate Package Wastes: Recycling and Use in Composites. ENERGIES 2021. [DOI: 10.3390/en14217306] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Plastics are versatile materials used in a variety of sectors that have seen a rapid increase in their global production. Millions of tonnes of plastic wastes are generated each year, which puts pressure on plastic waste management methods to prevent their accumulation within the environment. Recycling is an attractive disposal method and aids the initiative of a circular plastic economy, but recycling still has challenges to overcome. This review starts with an overview of the current European recycling strategies for solid plastic waste and the challenges faced. Emphasis lies on the recycling of polyolefins (POs) and polyethylene terephthalate (PET) which are found in plastic packaging, as packaging contributes a signification proportion to solid plastic wastes. Both sections, the recycling of POs and PET, discuss the sources of wastes, chemical and mechanical recycling, effects of recycling on the material properties, strategies to improve the performance of recycled POs and PET, and finally the applications of recycled POs and PET. The review concludes with a discussion of the future potential and opportunities of recycled POs and PET.
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23
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Chemical Recycling of PET in the Presence of the Bio-Based Polymers, PLA, PHB and PEF: A Review. SUSTAINABILITY 2021. [DOI: 10.3390/su131910528] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The great increase in the production and consumption of plastics has resulted in large amounts of plastic wastes, creating a serious problem in terms of their environmentally friendly disposal. The need for the production of more environmentally friendly polymers gave birth to the production of biodegradable, and more recently, biobased polymers, used in the production of biodegradable or biobased plastics. Although the percentage of currently produced bioplastics is rather small, almost 1% compared to petrochemical-based plastics, inevitably is going to significantly increase in the near future due to strict legislation recently posed by the European Union and other countries’ Governments. Thus, recycling strategies that have been developed could be disturbed and the economic balance of this sector could be destabilized. In the present review, the recycling of the polymer mainly used in food plastic packaging, i.e., poly(ethylene terephthalate), PET is examined together with its counterparts from the biobased polymers, i.e., poly(lactic acid), PLA (already replacing PET in several applications), poly(3-hydroxybutyrate), PHB and poly(ethylene furanoate), PEF. Methods for the chemical recycling of these materials together with the chemical products obtained are critically reviewed. Specifically, hydrolysis, alcoholysis and glycolysis. Hydrolysis (i.e., the reaction with water) under different environments (alkaline, acidic, neutral), experimental conditions and catalysts results directly in the production of the corresponding monomers, which however, should be separated in order to be re-used for the re-production of the respective polymer. Reaction conditions need to be optimized with a view to depolymerize only a specific polymer, while the others remain intact. Alcoholysis (i.e., the reaction with some alcohol, methanol or ethanol) results in methyl or ethyl esters or diesters that again could be used for the re-production of the specific polymer or as a source for producing other materials. Glycolysis (reaction with some glycol, such as ethylene, or diethylene glycol) is much studied for PET, whereas less studied for the biopolymers and seems to be a very promising technique. Oligomers having two terminal hydroxyl groups are produced that can be further utilized as starting materials for other value-added products, such as unsaturated polyester resins, methacrylated crosslinked resins, biodegradable polyurethanes, etc. These diols derived from both PET and the bio-based polymers can be used simultaneously without the need for an additional separation step, in the synthesis of final products incorporating biodegradable units in their chemical structure.
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24
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Ju Z, Zhou L, Lu X, Li Y, Yao X, Cheng S, Chen G, Ge C. Mechanistic insight into the roles of anions and cations in the degradation of poly(ethylene terephthalate) catalyzed by ionic liquids. Phys Chem Chem Phys 2021; 23:18659-18668. [PMID: 34612403 DOI: 10.1039/d1cp02038b] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Ionic liquids (ILs) have shown high catalytic activity in the degradation of poly(ethylene terephthalate) (PET), but the effects of the anions and cations, as well as the mechanism, remain ambiguous. Glycolysis is an important recycling method that converts waste PET into monomers through various chemical reactions. To reveal the role of ILs and the molecular mechanism of the glycolysis of PET, density functional theory (DFT) calculations have been carried out for the possible pathways for the generation of bis(hydroxyethyl)terephthalate (BHET) catalyzed by isolated anions/cations and ion pairs at different sites. The pathway with the lowest barrier for the glycolysis of PET is the cleavage of the C-O ester bond, which generates the BHET monomer. The synergistic effects of the cations and anions play a critical role in the glycolysis of PET. The cations mainly attack the carbonyl oxygen of PET to catalyze the reaction, and the anions mainly form strong H-bonds with PET and ethylene glycol (EG). In terms of the mechanism, the H-bonds render the hydroxyl oxygen of EG more electronegative. The cation coordinates the carbonyl oxygen of the ester, and the hydroxyl oxygen of EG attacks the ester group carbon of PET, with proton transfer to the carbonyl oxygen. A four-membered-ring transition state would be formed by PET, EG, and the IL catalyst, which regularly accelerates the degradation of PET. These results provide fundamental help in understanding the roles of ILs and the mechanism of IL-catalyzed PET degradation.
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Affiliation(s)
- Zhaoyang Ju
- College of Chemical & Material Engineering, Quzhou University, Quzhou 324000, P. R. China.
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25
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Ramasamy BSS, Palanisamy S. A review on occurrence, characteristics, toxicology and treatment of nanoplastic waste in the environment. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:43258-43273. [PMID: 34173146 DOI: 10.1007/s11356-021-14883-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 06/09/2021] [Indexed: 06/13/2023]
Abstract
Nanoplastics (NPs) have showed hotspot of discussion in recent years due to their impact in environment as a futuristic major pollutant in water, soil and air. In this correspondence review on the occurrence of nanoplastics and its effect at the environment as a waste have been overviewed and assimilated. It has the direct or indirect effect on aquatic and terrestrial geographical living beings due to its toxicity. The review revealed the major lacking in the field of analysis, database of contaminant quantity and legislative support to essential eradication on the existing imminent pollutant effects. A brief discussion about properties and characters of nanoplastics has been done. The environment exposed with macroplastics, microplastics and nanoplastics has abundantly contaminated the ecosystem surrounding it. Recent studies reveal that the major health effect by nanosize particles has mainly induced toxicity to the aquatic and terrestrial animals when compared to microsize particles and macrosize particles. The drastic effects and its toxicity in living ecosystem due to nanoplastics have been shown. The occurring waste is supposed to manage from environment by treating before entering into environment. The degradation methods for treatment of nanoplastics have been discussed in this review work.
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Affiliation(s)
| | - Shanmugam Palanisamy
- Department of Chemical Engineering, Kongu Engineering College, Erode, 638 060, India.
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26
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Ghasemi MH, Neekzad N, Ajdari FB, Kowsari E, Ramakrishna S. Mechanistic aspects of poly(ethylene terephthalate) recycling-toward enabling high quality sustainability decisions in waste management. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:43074-43101. [PMID: 34146328 DOI: 10.1007/s11356-021-14925-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Accepted: 06/11/2021] [Indexed: 06/12/2023]
Abstract
Since plastic waste pollution is a severe environmental concern in modern life, the demand for recycling poly(ethylene terephthalate) (PET) has increased due to its versatile applications. Taking advantage of plastic recycling methods creates the chances of minimizing overall crude oil-based materials consumption, and as a result, greenhouse gasses, specifically CO2, will be decreased. Although many review articles have been published on plastic recycling methods from different aspects, a few review articles exist to investigate the organic reaction mechanism in plastic recycling. This review aims to describe other processes for recycling bottle waste of PET, considering the reaction mechanism. Understanding the reaction mechanism offers practical solutions toward protecting the environment against disadvantageous outgrowths rising from PET wastes. PET recycling aims to transform into a monomer/oligomer to produce new materials from plastic wastes. It is an application in various fields, including the food and beverage industry, packaging, and textile applications, to protect the environment from contamination and introduce a green demand for the near future. In this review, the chemical glycolysis process as an outstanding recycling technique for PET is also discussed, emphasizing the catalysts' performance, reaction conditions and methods, degradation agents, the kinetics of reactions, and reprocessing products. In general, a correct understanding of the PET recycling reaction mechanism leads to making the right decisions in waste management.
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Affiliation(s)
- Mohammad Hadi Ghasemi
- Applied Chemistry Research Group, ACECR-Tehran Organization, PO Box 13145-186, Tehran, Iran
| | - Nariman Neekzad
- Department of Chemistry, Amirkabir University of Technology, No. 424, Hafez Avenue, Tehran, 1591634311, Iran
| | | | - Elaheh Kowsari
- Department of Chemistry, Amirkabir University of Technology, No. 424, Hafez Avenue, Tehran, 1591634311, Iran.
| | - Seeram Ramakrishna
- Department of Mechanical Engineering, Center for Nanofibers and Nanotechnology, National University of Singapore, Singapore, 119260, Singapore.
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27
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Damayanti, Wu HS. Strategic Possibility Routes of Recycled PET. Polymers (Basel) 2021; 13:1475. [PMID: 34063330 PMCID: PMC8125656 DOI: 10.3390/polym13091475] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 04/27/2021] [Accepted: 04/28/2021] [Indexed: 12/31/2022] Open
Abstract
The polyethylene terephthalate (PET) application has many challenges and potential due to its sustainability. The conventional PET degradation was developed for several technologies to get higher yield products of ethylene glycol, bis(2-hydroxyethyl terephthalate) and terephthalic acid. The chemical recycling of PET is reviewed, such as pyrolysis, hydrolysis, methanolysis, glycolysis, ionic-liquid, phase-transfer catalysis and combination of glycolysis-hydrolysis, glycolysis-methanolysis and methanolysis-hydrolysis. Furthermore, the reaction kinetics and reaction conditions were investigated both theoretically and experimentally. The recycling of PET is to solve environmental problems and find another source of raw material for petrochemical products and energy.
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Affiliation(s)
- Damayanti
- Department of Chemical Engineering, Institut Teknologi Sumatera, Lampung Selatan, Lampung 35365, Indonesia;
- Department of Chemical Engineering and Materials Science, Yuan Ze University, 135 Yuan-Tung Road, Chung-Li, Taoyuan 32003, Taiwan
| | - Ho-Shing Wu
- Department of Chemical Engineering and Materials Science, Yuan Ze University, 135 Yuan-Tung Road, Chung-Li, Taoyuan 32003, Taiwan
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28
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Laldinpuii Z, Lalhmangaihzuala S, Pachuau Z, Vanlaldinpuia K. Depolymerization of poly(ethylene terephthalate) waste with biomass-waste derived recyclable heterogeneous catalyst. WASTE MANAGEMENT (NEW YORK, N.Y.) 2021; 126:1-10. [PMID: 33730654 DOI: 10.1016/j.wasman.2021.02.056] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Revised: 02/01/2021] [Accepted: 02/24/2021] [Indexed: 06/12/2023]
Abstract
Poly(ethylene terephthalate) (PET) is one of the most widely used polymeric materials in chemical industry representing about 13% of the world's production. With the exponentially increasing consumption of plastics combined with its non-biodegradability, the accumulation of plastic waste in the environment rises steeply and its recycling has attracted enormous attention among researchers in recent years. In this present work, we describe bamboo leaf ash (BLA) as a bio-waste derived recyclable heterogeneous catalyst for the depolymerization of waste PET. The prepared catalyst was characterized by FT-IR, XRD, SEM, TEM, EDX, TGA and BET analyses to assess its morphology and composition. Postconsumer PET bottles were shredded and processed with 20 wt% BLA and 16 equivalents of ethylene glycol (EG) at 190 °C for 3.5 h under atmospheric pressure to give recrystallized bis(2-hydroxyethyl) terephthalate (BHET) monomer in 83% yield. The catalyst can be reused for four catalytic cycles and the residual EG was recovered for subsequent catalytic reactions. Excellent activity, cost-free, environmental-friendliness and ease of preparation, handling and reusability of the catalyst with simple work-up procedure are the notable advantages of this protocol.
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Affiliation(s)
- Zathang Laldinpuii
- Department of Chemistry, Pachhunga University College Campus, Mizoram University, Aizawl 796001, Mizoram, India; Department of Chemistry, Mizoram University, Tanhril, Aizawl 796004, Mizoram, India
| | - Samson Lalhmangaihzuala
- Department of Chemistry, Pachhunga University College Campus, Mizoram University, Aizawl 796001, Mizoram, India; Department of Chemistry, Mizoram University, Tanhril, Aizawl 796004, Mizoram, India
| | - Zodinpuia Pachuau
- Department of Chemistry, Mizoram University, Tanhril, Aizawl 796004, Mizoram, India
| | - Khiangte Vanlaldinpuia
- Department of Chemistry, Pachhunga University College Campus, Mizoram University, Aizawl 796001, Mizoram, India.
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Affiliation(s)
- Jonathan M. Millican
- Macromolecular Chemistry II, Bavarian Polymer Institute, University of Bayreuth, Universitätsstrasse 30, 95440 Bayreuth, Germany
| | - Seema Agarwal
- Macromolecular Chemistry II, Bavarian Polymer Institute, University of Bayreuth, Universitätsstrasse 30, 95440 Bayreuth, Germany
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30
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Kosloski-Oh SC, Wood ZA, Manjarrez Y, de Los Rios JP, Fieser ME. Catalytic methods for chemical recycling or upcycling of commercial polymers. MATERIALS HORIZONS 2021; 8:1084-1129. [PMID: 34821907 DOI: 10.1039/d0mh01286f] [Citation(s) in RCA: 86] [Impact Index Per Article: 28.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Polymers (plastics) have transformed our lives by providing access to inexpensive and versatile materials with a variety of useful properties. While polymers have improved our lives in many ways, their longevity has created some unintended consequences. The extreme stability and durability of most commercial polymers, combined with the lack of equivalent degradable alternatives and ineffective collection and recycling policies, have led to an accumulation of polymers in landfills and oceans. This problem is reaching a critical threat to the environment, creating a demand for immediate action. Chemical recycling and upcycling involve the conversion of polymer materials into their original monomers, fuels or chemical precursors for value-added products. These approaches are the most promising for value-recovery of post-consumer polymer products; however, they are often cost-prohibitive in comparison to current recycling and disposal methods. Catalysts can be used to accelerate and improve product selectivity for chemical recycling and upcycling of polymers. This review aims to not only highlight and describe the tremendous efforts towards the development of improved catalysts for well-known chemical recycling processes, but also identify new promising methods for catalytic recycling or upcycling of the most abundant commercial polymers.
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Affiliation(s)
- Sophia C Kosloski-Oh
- Department of Chemistry, University of Southern California, Los Angeles, CA 90089, USA.
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Laldinpuii ZT, Lalmuanpuia C, Lalhmangaihzuala S, Khiangte V, Pachuau Z, Vanlaldinpuia K. Biomass waste-derived recyclable heterogeneous catalyst for aqueous aldol reaction and depolymerization of PET waste. NEW J CHEM 2021. [DOI: 10.1039/d1nj03225a] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Eco-friendly biomass waste-derived recyclable heterogeneous catalyst for aldol reaction in water and for methanolysis of PET waste.
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Affiliation(s)
- Z. T. Laldinpuii
- Department of Chemistry, Mizoram University, Pachhunga University College Campus, Aizawl, Mizoram 796001, India
- Department of Chemistry, Mizoram University, Aizawl, Mizoram 796004, India
| | - Chhakchhuak Lalmuanpuia
- Department of Chemistry, Mizoram University, Pachhunga University College Campus, Aizawl, Mizoram 796001, India
- Department of Chemistry, Mizoram University, Aizawl, Mizoram 796004, India
| | - Samson Lalhmangaihzuala
- Department of Chemistry, Mizoram University, Pachhunga University College Campus, Aizawl, Mizoram 796001, India
- Department of Chemistry, Mizoram University, Aizawl, Mizoram 796004, India
| | - Vanlalngaihawma Khiangte
- Department of Chemistry, Mizoram University, Pachhunga University College Campus, Aizawl, Mizoram 796001, India
- Department of Chemistry, Mizoram University, Aizawl, Mizoram 796004, India
| | - Zodinpuia Pachuau
- Department of Chemistry, Mizoram University, Aizawl, Mizoram 796004, India
| | - Khiangte Vanlaldinpuia
- Department of Chemistry, Mizoram University, Pachhunga University College Campus, Aizawl, Mizoram 796001, India
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Glycolysis of Poly(Ethylene Terephthalate) Using Biomass-Waste Derived Recyclable Heterogeneous Catalyst. Polymers (Basel) 2020; 13:polym13010037. [PMID: 33374171 PMCID: PMC7794874 DOI: 10.3390/polym13010037] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 12/16/2020] [Accepted: 12/16/2020] [Indexed: 11/21/2022] Open
Abstract
Plastic production has increased by almost 200-fold annually from 2 million metric tons per year in 1950s to 359 million metric tons in 2018. With this rapidly increasing production, plastic pollution has become one of the most demanding environmental issues and tremendous efforts have been initiated by the research community for its disposal. In this present study, we reported for the first time, a biomass-waste-derived heterogeneous catalyst prepared from waste orange peel for the depolymerisation of poly(ethylene terephthalate) (PET) to its monomer, bis(2-hydroxyethyl terephthalate) (BHET). The prepared orange peel ash (OPA) catalyst was well-characterised using techniques such as IR, inductively coupled plasma (ICP)-OES (Optical Emission Spectrometry), XRD, X-ray fluorescence (XRF), SEM, energy-dispersive X-ray spectroscopy (EDX), TEM, BET (Brunauer-Emmett-Teller) and TGA. The catalyst was found to be composed of basic sites, high surface area, and a notable type-IV N2 adsorption–desorption isotherm indicating the mesoporous nature of the catalyst, which might have eventually enhanced the rate of the reaction as well as the yield of the product. The catalyst completely depolymerises PET within 90 min, producing 79% of recrystallised BHET. The ability of reusing the catalysts for 5 consecutive runs without significant depreciation in the catalytic activity and its eco- and environmental-friendliness endorses this protocol as a greener route for PET recycling.
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Poulose AM, Elnour AY, Kumar NS, Alhamidi A, George J, Al‐Ghurabi EH, Boumaza M, Al‐Zahrani S. Utilization of polyethylene terephthalate waste as a carbon filler in polypropylene matrix: Investigation of mechanical, rheological, and thermal properties. J Appl Polym Sci 2020. [DOI: 10.1002/app.50292] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Anesh Manjaly Poulose
- Department of Chemical Engineering, Sabic Polymer Research Center King Saud University Riyadh Saudi Arabia
| | | | | | - Abdullah Alhamidi
- Department of Chemical Engineering King Saud University Riyadh Saudi Arabia
| | - Justin George
- Centre for Advanced Composite Materials The University of Auckland Auckland New Zealand
| | | | - Mourad Boumaza
- Department of Chemical Engineering King Saud University Riyadh Saudi Arabia
| | - Saeed Al‐Zahrani
- Department of Chemical Engineering, Sabic Polymer Research Center King Saud University Riyadh Saudi Arabia
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Preparation and Characterization of Electrospun Collagen Based Composites for Biomedical Applications. MATERIALS 2020; 13:ma13183961. [PMID: 32906790 PMCID: PMC7559754 DOI: 10.3390/ma13183961] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 09/01/2020] [Accepted: 09/04/2020] [Indexed: 01/22/2023]
Abstract
Electrospinning is a widely used technology for obtaining nanofibers from synthetic and natural polymers. In this study, electrospun mats from collagen (C), polyethylene terephthalate (PET) and a blend of the two (C-PET) were prepared and stabilized through a cross-linking process. The aim of this research was to prepare and characterize the nanofiber structure by Fourier-transform infrared with attenuated total reflectance spectroscopy (FTIR-ATR) in close correlation with dynamic vapor sorption (DVS). The studies indicated that C-PET nanofibrous mats shows improved mechanical properties compared to collagen samples. A correlation between morphological, structural and cytotoxic proprieties of the studied samples were emphasized and the results suggest that the prepared nanofiber mats could be a promising candidate for tissue-engineering applications, especially dermal applications.
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Raheem AB, Noor ZZ, Hassan A, Abd Hamid MK, Samsudin SA, Sabeen AH. Current developments in chemical recycling of post-consumer polyethylene terephthalate wastes for new materials production: A review. JOURNAL OF CLEANER PRODUCTION 2019; 225:1052-1064. [DOI: 10.1016/j.jclepro.2019.04.019] [Citation(s) in RCA: 94] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
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36
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Castro AMD, Carniel A, Stahelin D, Chinelatto Junior LS, Honorato HDA, de Menezes SMC. High-fold improvement of assorted post-consumer poly(ethylene terephthalate) (PET) packages hydrolysis using Humicola insolens cutinase as a single biocatalyst. Process Biochem 2019. [DOI: 10.1016/j.procbio.2019.03.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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37
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Effective catalysts derived from waste ostrich eggshells for glycolysis of post-consumer PET bottles. CHEMICAL PAPERS 2019. [DOI: 10.1007/s11696-019-00710-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Ronkay F, Molnár B, Szalay F, Nagy D, Bodzay B, Sajó IE, Bocz K. Development of Flame-Retarded Nanocomposites from Recycled PET Bottles for the Electronics Industry. Polymers (Basel) 2019; 11:E233. [PMID: 30960217 PMCID: PMC6419026 DOI: 10.3390/polym11020233] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2018] [Revised: 01/25/2019] [Accepted: 01/25/2019] [Indexed: 12/04/2022] Open
Abstract
Recycled polyethylene-terephthalate (rPET) nanocomposites of reduced flammability were prepared by combining aluminum-alkylphosphinate (AlPi) flame retardant (FR) and natural montmorillonite (MMT), in order to demonstrate that durable, technical products can be produced from recycled materials. During the development of the material, by varying the FR content, the ratio and the type of MMTs, rheological, morphological, mechanical and flammability properties of the nanocomposites were comprehensively investigated. Related to the differences between the dispersion and nucleation effect of MMT and organo-modified MMT (oMMT) in rPET matrix, analyzed by Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray Spectroscopy (EDS) and Differential Scanning Calorimetry (DSC), mechanical properties of the nanocomposites changed differently. The flexural strength and modulus were increased more significantly by adding untreated MMT than by the oMMT, however the impact strength was decreased by both types of nanofillers. The use of different type of MMTs resulted in contradictory flammability test result; time-to-ignition (TTI) during cone calorimeter tests decreased when oMMT was added to the rPET, however MMT addition resulted in an increase of the TTI also when combined with 4% FR. The limiting oxygen index (LOI) of the oMMT containing composites decreased independently from the FR content, however, the MMT increased it noticeably. V0 classification according to the UL-94 standard was achieved with as low as 4% FR and 1% MMT content. The applicability of the upgraded recycled material was proved by a pilot experiment, where large-scale electronic parts were produced by injection molding and characterized with respect to the commercially available counterparts.
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Affiliation(s)
- Ferenc Ronkay
- Department of Polymer Engineering, Faculty of Mechanical Engineering, Budapest University ofTechnology and Economics, Műegyetem rkp. 3, H-1111 Budapest, Hungary.
- Imsys Ltd., Material Testing Laboratory, Mozaik Street 14/A., H-1033 Budapest, Hungary.
| | - Béla Molnár
- Department of Polymer Engineering, Faculty of Mechanical Engineering, Budapest University ofTechnology and Economics, Műegyetem rkp. 3, H-1111 Budapest, Hungary.
- Imsys Ltd., Material Testing Laboratory, Mozaik Street 14/A., H-1033 Budapest, Hungary.
| | - Ferenc Szalay
- Department of Polymer Engineering, Faculty of Mechanical Engineering, Budapest University ofTechnology and Economics, Műegyetem rkp. 3, H-1111 Budapest, Hungary.
| | - Dóra Nagy
- Department of Polymer Engineering, Faculty of Mechanical Engineering, Budapest University ofTechnology and Economics, Műegyetem rkp. 3, H-1111 Budapest, Hungary.
| | - Brigitta Bodzay
- Department of Organic Chemistry and Technology, Faculty of Chemical Technology and Biotechnology,Budapest University of Technology and Economics, Műegyetem rkp. 3, H-1111 Budapest, Hungary.
| | - István E Sajó
- Environmental Analytical and Geoanalytical Research Group, Szentágothai Research Centre, University ofPécs, Vasvári Pál str. 4., H-7622 Pécs, Hungary.
| | - Katalin Bocz
- Department of Organic Chemistry and Technology, Faculty of Chemical Technology and Biotechnology,Budapest University of Technology and Economics, Műegyetem rkp. 3, H-1111 Budapest, Hungary.
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Guo Z, Lindqvist K, de la Motte H. An efficient recycling process of glycolysis of PET in the presence of a sustainable nanocatalyst. J Appl Polym Sci 2018. [DOI: 10.1002/app.46285] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Zengwei Guo
- Swerea IVF, Department of Textile and Plastics, Box 104; SE-431 22 Mölndal Sweden
| | - Karin Lindqvist
- Swerea IVF, Department of Textile and Plastics, Box 104; SE-431 22 Mölndal Sweden
| | - Hanna de la Motte
- RISE Research Institutes of Sweden, Division Bioeconomy, Box 24036; SE-400 22 Göteborg Sweden
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Natarajan J, Madras G, Chatterjee K. Poly(ester amide)s from Poly(ethylene terephthalate) Waste for Enhancing Bone Regeneration and Controlled Release. ACS APPLIED MATERIALS & INTERFACES 2017; 9:28281-28297. [PMID: 28766935 DOI: 10.1021/acsami.7b09299] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The present study elucidates the facile synthesis and exceptional properties of a family of novel poly(ester amide)s (PEAs) based on bis(2-hydroxy ethylene) terephthalamide that was obtained from the poly(ethylene terephthalate) waste. Fourier transform infrared and 1H NMR were used to verify the presence of ester and amide in the polymer backbone. Differential scanning calorimetry data showed that the glass transition temperature decreased with as the chain length of dicarboxylic acids increased. Dynamic mechanical analysis and contact angle studies proved that the modulus values and hydrophobicity increased with as the chain lengths of dicarboxylic acids increased. In vitro hydrolytic degradation and dye release studies demonstrated that the degradation and release decreased with as the chain lengths of dicarboxylic acids increased. Modeling these data illustrated that degradation and release follow first-order degradation and zero-order release, respectively. The in vitro cytocompatibility studies confirmed the minimal toxicity characteristic of these polymers. Osteogenic studies proved that these polymers can be highly influential in diverting the cells toward osteogenic lineage. Alizarin red staining evinced the presence of twice the amount of calcium phosphate deposits by the cells on these polymers when compared to the control. The observed result was also corroborated by the increased expression of alkaline phosphatase. These findings were further validated by the markedly higher mRNA expressions for known osteogenic markers using real time polymerase chain reaction. Therefore, these polymers efficiently promoted osteogenesis. This study demonstrates that the physical properties, degradation, and release kinetics can be altered to meet the specific requirements in organ regeneration as well as facilitate simultaneous polymer resorption through control of the chain length of the monomers. The findings of this study have significant implications for designing cost-effective biodegradable polymers for tissue engineering.
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Affiliation(s)
- Janeni Natarajan
- Centre for Nano Science and Engineering, ‡Department of Chemical Engineering, and §Department of Materials Engineering, Indian Institute of Science , Bangalore 560012, India
| | - Giridhar Madras
- Centre for Nano Science and Engineering, ‡Department of Chemical Engineering, and §Department of Materials Engineering, Indian Institute of Science , Bangalore 560012, India
| | - Kaushik Chatterjee
- Centre for Nano Science and Engineering, ‡Department of Chemical Engineering, and §Department of Materials Engineering, Indian Institute of Science , Bangalore 560012, India
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Reactive Extrusion of Polyethylene Terephthalate Waste and Investigation of Its Thermal and Mechanical Properties after Treatment. INTERNATIONAL JOURNAL OF CHEMICAL ENGINEERING 2017. [DOI: 10.1155/2017/5361251] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
This study investigates treating polyethylene terephthalate (PET) waste water bottles with different mass of ethylene glycol (EG) using reactive extrusion technique at a temperature of 260°C. The study puts emphases on evaluating the thermal, mechanical, and chemical characteristics of the treated polyethylene terephthalate. The properties of the treated PET from the extruder were analyzed using FT-IR, TGA, DSC, and nanoindentation. The melt flow indexes (MFI) of both treated and untreated PET were also measured and compared. Thermal properties such as melting temperature (Tm) for treating PET showed an inversely proportional behavior with the EG concentrations. The FT-IR analysis was used to investigate the formation of new linkages like hydrogen bonds between PET and EG due to the hydroxyl and carbonyl groups. Nanoindentation results revealed that both the mechanical characteristics, elastic modulus and hardness, decrease with increasing EG concentration. On the other hand, the melt flow index of treated PET exhibited an increase with increasing EG concentration in the PET matrix.
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