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Zhang KH, Bao LJ, Wang Y, Yang HM, Gao Y, Tang C, Wu CC, Zeng EY. Effects of polymer matrix and temperature on pyrolysis of tetrabromobisphenol A: Product profiles and transformation pathways. JOURNAL OF HAZARDOUS MATERIALS 2024; 474:134806. [PMID: 38850946 DOI: 10.1016/j.jhazmat.2024.134806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2024] [Revised: 05/27/2024] [Accepted: 06/02/2024] [Indexed: 06/10/2024]
Abstract
Plastics are crucial constituents in electronic waste (e-waste) and part of the issue in e-waste recycling and environmental protection. However, previous studies have mostly focused on plastic recovery or thermal behavior of flame retardants, but not both simultaneously. The present study simulated the process of e-waste thermal treatment to explore tetrabromobisphenol A (TBBPA) pyrolysis at various temperatures using polystyrene (PS), polyvinyl chloride (PVC), and e-waste plastics as polymer matrices. Pyrolysis of TBBPA produced bromophenol, bromoacetophenone, bromobenzaldehyde, and bromobisphenol A. Co-pyrolysis with the polymer matrices increased emission factors by 1 - 2 orders of magnitude. The pyrolytic products of TBBPA, TBBPA+PS, and TBBPA+PVC were mainly low-brominated bisphenol A, while that of TBBPA in e-waste plastics was consistently bromophenol. Increasing temperature drove up the proportions of gaseous and particulate products, but lowered the relative abundances of inner wall adsorbed and residual products in pyrolysis of pure TBBPA. In co-pyrolysis of TBBPA with polymer matrix, the proportions of products in different phases were no longer governed solely by temperature, but also by polymer matrix. Co-pyrolysis of TBBPA with PS generated various bromophenols, while that with PVC produced chlorophenols and chlorobrominated bisphenol A. Transformation pathways, deduced by ab initio calculations, include hydrogenation-debromination, isopropylphenyl bond cleavage, oxidation, and chlorination.
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Affiliation(s)
- Kai-Hui Zhang
- Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou 511443, China
| | - Lian-Jun Bao
- Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou 511443, China; Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Clusters (Ministry of Education), School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
| | - Yu Wang
- Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou 511443, China
| | - Han-Ming Yang
- Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou 511443, China
| | - Yanpeng Gao
- Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China
| | - Caiming Tang
- Laboratory of Advanced Analytical Chemistry and Detection Technology, Research Center for Eco-Environmental Engineering, Dongguan University of Technology, Dongguan 523808, China
| | - Chen-Chou Wu
- Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou 511443, China; Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Clusters (Ministry of Education), School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
| | - Eddy Y Zeng
- Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Clusters (Ministry of Education), School of Environment and Energy, South China University of Technology, Guangzhou 510006, China.
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Leri AC, Hettithanthri O, Bolan S, Zhang T, Unrine J, Myneni S, Nachman DR, Tran HT, Phillips AJ, Hou D, Wang Y, Vithanage M, Padhye LP, Jasemi Zad T, Heitz A, Siddique KHM, Wang H, Rinklebe J, Kirkham MB, Bolan N. Bromine contamination and risk management in terrestrial and aquatic ecosystems. JOURNAL OF HAZARDOUS MATERIALS 2024; 469:133881. [PMID: 38422740 DOI: 10.1016/j.jhazmat.2024.133881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Revised: 01/18/2024] [Accepted: 02/22/2024] [Indexed: 03/02/2024]
Abstract
Bromine (Br) is widely distributed through the lithosphere and hydrosphere, and its chemistry in the environment is affected by natural processes and anthropogenic activities. While the chemistry of Br in the atmosphere has been comprehensively explored, there has never been an overview of the chemistry of Br in soil and aquatic systems. This review synthesizes current knowledge on the sources, geochemistry, health and environmental threats, remediation approaches, and regulatory guidelines pertaining to Br pollution in terrestrial and aquatic environments. Volcanic eruptions, geothermal streams, and seawater are the major natural sources of Br. In soils and sediments, Br undergoes natural cycling between organic and inorganic forms, with bromination reactions occurring both abiotically and through microbial activity. For organisms, Br is a non-essential element; it is passively taken up by plant roots in the form of the Br- anion. Elevated Br- levels can limit plant growth on coastal soils of arid and semi-arid environments. Br is used in the chemical industry to manufacture pesticides, flame retardants, pharmaceuticals, and other products. Anthropogenic sources of organobromine contaminants in the environment are primarily wastewater treatment, fumigants, and flame retardants. When aqueous Br- reacts with oxidants in water treatment plants, it can generate brominated disinfection by-products (DBPs), and exposure to DBPs is linked to adverse human health effects including increased cancer risk. Br- can be removed from aquatic systems using adsorbents, and amelioration of soils containing excess Br- can be achieved by leaching, adding various amendments, or phytoremediation. Developing cost-effective methods for Br- removal from wastewater would help address the problem of toxic brominated DBPs. Other anthropogenic organobromines, such as polybrominated diphenyl ether (PBDE) flame retardants, are persistent, toxic, and bioaccumulative, posing a challenge in environmental remediation. Future research directives for managing Br pollution sustainably in various environmental settings are suggested here.
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Affiliation(s)
- Alessandra C Leri
- Department of Natural Sciences, Marymount Manhattan College, 221 E 71st St., New York, NY 10021, United States.
| | - Oshadi Hettithanthri
- Ecosphere Resilience Research Centre, Faculty of Applied Sciences, University of Sri Jayewardenepura, Nugegoda, 10250, Sri Lanka
| | - Shiv Bolan
- UWA School of Agriculture and Environment, The University of Western Australia, Perth, Western Australia 6009, Australia; The UWA Institute of Agriculture, The University of Western Australia, Perth, Western Australia 6009, Australia; Healthy Environments And Lives (HEAL) National Research Network, Canberra, Australia
| | - Tao Zhang
- Beijing Key Laboratory of Farmland Soil Pollution Prevention-Control and Remediation, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, People's Republic of China
| | - Jason Unrine
- Department of Plant and Soil Sciences, University of Kentucky, Lexington, KY 40546, United States; Kentucky Water Research Institute, University of Kentucky, Lexington, KY 40506, United States
| | - Satish Myneni
- Department of Geosciences, Princeton Univ., Princeton, NJ 08544, United States
| | - Danielle R Nachman
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, United States
| | - Huu Tuan Tran
- Laboratory of Ecology and Environmental Management, Science and Technology Advanced Institute, Van Lang University, Ho Chi Minh City, Viet Nam; Faculty of Applied Technology, School of Technology, Van Lang University, Ho Chi Minh City, Viet Nam
| | - Ankur J Phillips
- Department of Microbiology, College of Basic Sciences and Humanities, Govind Ballabh Pant University of Agriculture and Technology, Pantnagar, Uttarakhand 263145, India
| | - Deyi Hou
- School of Environment, Tsinghua University, Beijing 100084, People's Republic of China
| | - Yidong Wang
- School of Environment, Tsinghua University, Beijing 100084, People's Republic of China
| | - Meththika Vithanage
- Ecosphere Resilience Research Centre, Faculty of Applied Sciences, University of Sri Jayewardenepura, Nugegoda, 10250, Sri Lanka; UWA School of Agriculture and Environment, The University of Western Australia, Perth, Western Australia 6009, Australia; Sustainability Cluster, University of Petroleum and Energy Studies, Dehradun, India
| | - Lokesh P Padhye
- Department of Civil and Environmental Engineering, Faculty of Engineering, The University of Auckland, Auckland 1010, New Zealand
| | - Tahereh Jasemi Zad
- Department of Civil and Environmental Engineering, Faculty of Engineering, The University of Auckland, Auckland 1010, New Zealand
| | - Anna Heitz
- Curtin Water Quality Research Centre, Department of Chemistry, Curtin University, GPO Box U1987, Perth, WA 6845, Australia
| | - Kadambot H M Siddique
- UWA School of Agriculture and Environment, The University of Western Australia, Perth, Western Australia 6009, Australia; The UWA Institute of Agriculture, The University of Western Australia, Perth, Western Australia 6009, Australia
| | - Hailong Wang
- Biochar Engineering Technology Research Center of Guangdong Province, School of Environmental and Chemical Engineering, Foshan University, Foshan, Guangdong 528000, People's Republic of China; Key Laboratory of Soil Contamination Bioremediation of Zhejiang Province, Zhejiang A&F University, Hangzhou, Zhejiang 311300, People's Republic of China
| | - Jörg Rinklebe
- University of Wuppertal, School of Architecture and Civil Engineering, Institute of Foundation Engineering, Water, and Waste-Management, Laboratory of Soil, and Groundwater-Management, Pauluskirchstraße 7, Wuppertal 42285, Germany
| | - M B Kirkham
- Department of Agronomy, Throckmorton Plant Sciences Center, Kansas State University, Manhattan, KS 66506, United States
| | - Nanthi Bolan
- UWA School of Agriculture and Environment, The University of Western Australia, Perth, Western Australia 6009, Australia; The UWA Institute of Agriculture, The University of Western Australia, Perth, Western Australia 6009, Australia; Healthy Environments And Lives (HEAL) National Research Network, Canberra, Australia
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Amodio L, López J, Souza A, Cueto J, Hernando H, Pizarro P, Serrano D. Simultaneous removal of brominated and chlorinated species during the production of oils by e-waste plastics catalytic hydropyrolysis. JOURNAL OF HAZARDOUS MATERIALS 2024; 465:133357. [PMID: 38157819 DOI: 10.1016/j.jhazmat.2023.133357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 12/15/2023] [Accepted: 12/21/2023] [Indexed: 01/03/2024]
Abstract
The production of added-value chemicals via pyrolysis of plastic wastes, such as those from electrical and electronic equipment (WEEE), needs addressing their usual contamination with halogens (mainly Br and Cl). This work compares the conversion via pyrolysis and hydropyrolysis of a real WEEE plastic, having a complex composition, in two different reactor configurations: down-flow (DF) and up-flow (UF). Likewise, the effects of incorporating a Pd/Al2O3 catalyst and using two different pressures (1 and 6 bar) have been assessed. With the DF mode, pyrolysis at 1 bar leads to an oil yield above 80 wt% and a total halogen content of about 600 ppm (vs 1600 ppm in the water-washed WEEE plastic). Under DF catalytic hydropyrolysis at 6 bar, this high oil yield is maintained while its dehalogenation degree is improved (142 ppm). Operating with the up-flow configuration, under 6 bar and H2 presence, leads to some reduction in the oil yield (about 70 wt%) but significantly decreases the oil halogen content (55 ppm Cl and total elimination of Br). These results have been related to the slower pyrolysis and longer residence time in the thermal zone of the UF configuration, which favours the halogen-trapping effect of the char fraction, and the pressure-enhanced hydrodehalogenation activity of the catalyst. This study highlights the environmental benefits of the proposed process, emphasizing the lower halogen content in the resulting oils and promoting a more sustainable approach to plastic waste valorisation.
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Affiliation(s)
- Lidia Amodio
- Thermochemical Processes Unit, IMDEA Energy, Avda. Ramón de la Sagra 3, Móstoles, Madrid 28935, Spain; Chemical and Environmental Engineering Group, Rey Juan Carlos University, Móstoles, Madrid, Spain
| | - Julio López
- Thermochemical Processes Unit, IMDEA Energy, Avda. Ramón de la Sagra 3, Móstoles, Madrid 28935, Spain; Chemical and Environmental Engineering Group, Rey Juan Carlos University, Móstoles, Madrid, Spain
| | - Adriana Souza
- Thermochemical Processes Unit, IMDEA Energy, Avda. Ramón de la Sagra 3, Móstoles, Madrid 28935, Spain
| | - Jennifer Cueto
- Thermochemical Processes Unit, IMDEA Energy, Avda. Ramón de la Sagra 3, Móstoles, Madrid 28935, Spain
| | - Héctor Hernando
- Thermochemical Processes Unit, IMDEA Energy, Avda. Ramón de la Sagra 3, Móstoles, Madrid 28935, Spain
| | - Patricia Pizarro
- Thermochemical Processes Unit, IMDEA Energy, Avda. Ramón de la Sagra 3, Móstoles, Madrid 28935, Spain; Chemical and Environmental Engineering Group, Rey Juan Carlos University, Móstoles, Madrid, Spain
| | - David Serrano
- Thermochemical Processes Unit, IMDEA Energy, Avda. Ramón de la Sagra 3, Móstoles, Madrid 28935, Spain; Chemical and Environmental Engineering Group, Rey Juan Carlos University, Móstoles, Madrid, Spain.
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Ma C, Kumagai S, Saito Y, Yoshioka T, Huang X, Shao Y, Ran J, Sun L. Recent Advancements in Pyrolysis of Halogen-Containing Plastics for Resource Recovery and Halogen Upcycling: A State-of-the-Art Review. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:1423-1440. [PMID: 38197317 DOI: 10.1021/acs.est.3c09451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2024]
Abstract
Plastic waste has emerged as a serious issue due to its impact on environmental degradation and resource scarcity. Plastic recycling, especially of halogen-containing plastics, presents challenges due to potential secondary pollution and lower-value implementations. Chemical recycling via pyrolysis is the most versatile and robust approach for combating plastic waste. In this Review, we present recent advancements in halogen-plastic pyrolysis for resource utilization and the potential pathways from "reducing to recycling to upcycling" halogens. We emphasize the advanced management of halogen-plastics through copyrolysis with solid wastes (waste polymers, biomass, coal, etc.), which is an efficient method for dealing with mixed wastes to obtain high-value products while reducing undesirable substances. Innovations in catalyst design and reaction configurations for catalytic pyrolysis are comprehensively evaluated. In particular, a tandem catalysis system is a promising route for halogen removal and selective conversion of targeted products. Furthermore, we propose novel insights regarding the utilization and upcycling of halogens from halogen-plastics. This includes the preparation of halogen-based sorbents for elemental mercury removal, the halogenation-vaporization process for metal recovery, and the development of halogen-doped functional materials for new materials and energy applications. The reutilization of halogens facilitates the upcycling of halogen-plastics, but many efforts are needed for mutually beneficial outcomes. Overall, future investigations in the development of copyrolysis and catalyst-driven technologies for upcycling halogen-plastics are highlighted.
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Affiliation(s)
- Chuan Ma
- Key Laboratory of Low-grade Energy Utilization Technologies and Systems, Ministry of Education, School of Energy and Power Engineering, Chongqing University, Chongqing 400044, China
| | - Shogo Kumagai
- Graduate School of Environmental Studies, Tohoku University, 6-6-07 Aoba, Aramaki-aza, Aoba-ku, Sendai, Miyagi 980-8579, Japan
| | - Yuko Saito
- Graduate School of Environmental Studies, Tohoku University, 6-6-07 Aoba, Aramaki-aza, Aoba-ku, Sendai, Miyagi 980-8579, Japan
| | - Toshiaki Yoshioka
- Graduate School of Environmental Studies, Tohoku University, 6-6-07 Aoba, Aramaki-aza, Aoba-ku, Sendai, Miyagi 980-8579, Japan
| | - Xin Huang
- Key Laboratory of Low-grade Energy Utilization Technologies and Systems, Ministry of Education, School of Energy and Power Engineering, Chongqing University, Chongqing 400044, China
| | - Yunlin Shao
- Key Laboratory of Low-grade Energy Utilization Technologies and Systems, Ministry of Education, School of Energy and Power Engineering, Chongqing University, Chongqing 400044, China
| | - Jingyu Ran
- Key Laboratory of Low-grade Energy Utilization Technologies and Systems, Ministry of Education, School of Energy and Power Engineering, Chongqing University, Chongqing 400044, China
| | - Lushi Sun
- State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074, China
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5
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Xi Z, Gao R, Chen Z, Du H, Xu Z. In situ high-valued transformation of nonmetals in waste printed circuit boards into supercapacitor electrodes with excellent performance. RSC Adv 2024; 14:1386-1396. [PMID: 38174251 PMCID: PMC10763618 DOI: 10.1039/d3ra08125g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Accepted: 12/15/2023] [Indexed: 01/05/2024] Open
Abstract
Nonmetals in waste printed circuit boards after metal separation containing brominated resin and fiberglass are considered hazardous and low-recoveryvalue e-waste. However, if these nonmetals are not treated or are improperly treated, they can cause serious environmental pollution. Therefore, there is an urgent and significant need to develop an efficient recycling process for these nonmetals. Based on the concept of high-valued recycling of waste, this study in situ utilized such nonmetals to prepare a porous supercapacitor electrode through a facile carbonization, activation, and carbon thermal reduction process. The results indicated that the activation was a key role in constructing a porous structure. The optimal parameters for activation were a temperature of 800 °C, mass ratio of KOH to pyrolytic residues of 2, and an activation time of 1 h. The electrode materials exhibited a surface area of 589 m2 g-1 and hierarchical porous structures. In addition, the supercapacitors exhibited a capacitance of 77.14 mF cm-2 (62.5 mF cm-2) at 0.5 mA cm-2 (100 mV s-1). Moreover, the supercapacitors had excellent temperature resistance and adaptability. The capacitance retention was 89.36% and 90% at -50 °C and 100 °C after 10 000 cycles, respectively. This study provides a high-valued recycling strategy to utilize the nonmetals in e-waste as energy materials.
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Affiliation(s)
- Zhen Xi
- College of Chemistry and Chemical Engineering, Institute for Sustainable Energy and Resources, Qingdao University Qingdao, 308 Ningxia Road Qingdao 266071 P.R. China +86 15806391156 +86 18953271778
| | - Ruitong Gao
- College of Chemistry and Chemical Engineering, Institute for Sustainable Energy and Resources, Qingdao University Qingdao, 308 Ningxia Road Qingdao 266071 P.R. China +86 15806391156 +86 18953271778
| | - Zhaojun Chen
- College of Chemistry and Chemical Engineering, Institute for Sustainable Energy and Resources, Qingdao University Qingdao, 308 Ningxia Road Qingdao 266071 P.R. China +86 15806391156 +86 18953271778
| | - Hui Du
- College of Chemistry and Chemical Engineering, Institute for Sustainable Energy and Resources, Qingdao University Qingdao, 308 Ningxia Road Qingdao 266071 P.R. China +86 15806391156 +86 18953271778
| | - Zhenming Xu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University 800 Dongchuan Road Shanghai 200240 P.R. China
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Xu L, Li S, Zhang Y, Sun W, Pan L, Wang L. Non-isothermal thermal decomposition behavior and reaction kinetics of acrylonitrile butadiene styrene (ABS). JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 348:119080. [PMID: 37827086 DOI: 10.1016/j.jenvman.2023.119080] [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: 05/25/2023] [Revised: 07/23/2023] [Accepted: 08/30/2023] [Indexed: 10/14/2023]
Abstract
Environmental concerns associated with the rapid rising plastic consumption have led to the search for better waste utilization and management. Pyrolysis has emerged as an ideal and promising technique for energy extraction from plastic waste. The aim of this work is to explore the waste plastic pyrolysis behavior under non-isothermal heating conditions. The decomposition characteristics, reaction mechanism, kinetics and thermodynamics of a typical widely used thermosetting plastic, acrylonitrile butadiene styrene (ABS), were studied via coupled thermogravimetry, Fourier transform infrared spectrometry and gas chromatography-mass spectrometry analysis (TG-FTIR-GC/MS). Kinetic analysis showed the average Eα values are estimated to be 187.02, 188.55, 187.04 and 185.67 kJ/mol via advanced Vyazovkin, Flynn-Wall-Ozawa (FWO), Tang and Starink model-free method, respectively. Model-fitting CR and master-plots method indicated that f(α)=(1-α)n is the most probable reaction mechanism. The equation of kinetic compensation effect was further developed as lnA = -3.1955 + 0.1736 Eα. Based on these initial inferences, a new reaction scheme coupled with Particle Swarm Optimization (PSO) was put forward for modeling ABS pyrolysis. The optimized values of E, A and n are 198.07 kJ/mol, 7.61 × 1012 s-1 and 1.56, respectively. The predicted results showed that the experimental data can be well characterized by the optimized parameters from PSO, validating the effectiveness and accuracy of the inverse modeling procedure. Moreover, it is found that the volatile products are mainly composed of aromatic compounds, ketones, amines, esters, nitrile compounds, alkenes and amines. Based on the FT-IR and GC-MS results, the possible chemical reactions for ABS pyrolysis from molecular structure were proposed. Finally, thermodynamic analysis was carried out, the calculated values of enthalpy ΔH, Gibb's free energy ΔG and entropy ΔS indicated that non-spontaneous reactions with low favorability exists during ABS decomposition, the process is complex therefore extra energy is needed to promote the reaction. The obtained results should offer as an important reference for future disposal and thermochemical management of such polymer waste.
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Affiliation(s)
- Li Xu
- College of Architectural Science and Engineering, Yangzhou University, Yangzhou, 225127, China
| | - Shengcai Li
- College of Architectural Science and Engineering, Yangzhou University, Yangzhou, 225127, China.
| | - Youchao Zhang
- College of Architectural Science and Engineering, Yangzhou University, Yangzhou, 225127, China
| | - Wanghu Sun
- College of Architectural Science and Engineering, Yangzhou University, Yangzhou, 225127, China
| | - Longwei Pan
- School of Materials Engineering, Changshu Institute of Technology, Changshu, 215500, China
| | - Lei Wang
- School of Energy and Power, Jiangsu University of Science and Technology, Zhenjiang, 212013, China
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Preetam A, Dwivedi U, N Naik S, Pant KK, Kumar V. A feasible approach for the treatment of waste computer casing plastic using subcritical to supercritical acetone: Statistical modelling and optimization. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 345:118549. [PMID: 37421717 DOI: 10.1016/j.jenvman.2023.118549] [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: 04/27/2023] [Revised: 06/08/2023] [Accepted: 06/28/2023] [Indexed: 07/10/2023]
Abstract
Electronic waste (e-waste) usage has increased tremendously with the rapid evolution of technologies. The accumulated e-waste has now emerged as one of the crucial concerns regarding environmental pollution and human health. Recycling e-waste is commonly focused on metal recovery; nevertheless, a significant fraction of plastics (20-30%) are in e-waste. There is an indispensable need to focus on e-waste plastic recycling in an effective way, which has been mostly overlooked to date. An environmentally safe and efficient study is conducted using subcritical to supercritical acetone (SCA) to degrade the real waste computer casing plastics (WCCP) in the central composite design (CCD) of response surface methodology (RSM) to achieve the maximum oil yield of the product. The experiment parameters were varied in the temperature span of 150-300 °C, residence time between 30 and 120 min, solid/liquid ratio between 0.02 and 0.05 (g/ml), and NaOH amount from 0 to 0.5 g. Adding NaOH into the acetone helps to achieve efficient degradation and debromination efficiency. The study emphasized the attributes of oils and solid products recovered from the SCA-treated WCCP. The characterization of feed and formed products is performed with different characterization techniques such as TGA, CHNS, ICP-MS, FTIR, GC-MS, Bomb calorimeter, XRF, and FESEM. The highest oil yield achieved is 87.89% from the SCA process at 300 °C, in 120min, 0.05 S/L ratio, and 0.5 g of NaOH. GC-MS results disclose that the liquid product (oil) comprises single- and duplicate-ringed aromatic and oxygen-containing compounds. Isophorone is the significant component of the liquid product obtained. Furthermore, SCA's possible polymer degradation mechanistic route, bromine distribution, economic feasibility, and environmental aspect were also explored. This present work represents an environmentally friendly and promising approach for recycling the plastic fraction of e-waste and recovering valuable chemicals from WCCP.
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Affiliation(s)
- Amrita Preetam
- Supercritical Fluid Extraction Laboratory, Centre for Rural Development and Technology, IIT Delhi, 110016, India; Catalytic Reaction Engineering Laboratory, Chemical Engineering Department, Indian, IIT Delhi, 110016, India
| | - Uma Dwivedi
- Supercritical Fluid Extraction Laboratory, Centre for Rural Development and Technology, IIT Delhi, 110016, India; Catalytic Reaction Engineering Laboratory, Chemical Engineering Department, Indian, IIT Delhi, 110016, India
| | - S N Naik
- Supercritical Fluid Extraction Laboratory, Centre for Rural Development and Technology, IIT Delhi, 110016, India
| | - K K Pant
- Catalytic Reaction Engineering Laboratory, Chemical Engineering Department, Indian, IIT Delhi, 110016, India.
| | - Vivek Kumar
- Supercritical Fluid Extraction Laboratory, Centre for Rural Development and Technology, IIT Delhi, 110016, India
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Lahtela V, Mielonen K, Parkar P, Kärki T. The Effects of Bromine Additives on the Recyclability of Injection Molded Electronic Waste Polymers. GLOBAL CHALLENGES (HOBOKEN, NJ) 2023; 7:2300157. [PMID: 37970537 PMCID: PMC10632664 DOI: 10.1002/gch2.202300157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Revised: 08/31/2023] [Indexed: 11/17/2023]
Abstract
Excessive waste amounts, such as waste electrical and electronic equipment (WEEE) and plastic waste, have increased simultaneously with the development of society. Despite the increased material amounts, the recycling rates are too low and those have a great potential to contribute actions toward a circular economy. A certain restricted factor for recycling is the heterogenous nature of materials, such as WEEE-included additives. This study investigates the effects of a WEEE polymer including bromine on recycling ability, analyzing its physical and mechanical features. The study demonstrates that polymer sorting is profitable for WEEE polymers from the material qualitative perspective, because various processability and material features are achieved in the study between material categories, and especially unidentified polymers have the weakest features in the studied tests. The separation of bromine concentration is also recommended because bromine-free materials have more advanced features that can be confirmed by statistical analyses. The achieved results support the idea that novel circular economy actions have the potential for effective, efficient WEEE polymer recycling processes with technological innovations, especially when all variables (e.g., recycling cycles and process parameters) are observed and it enables an option to reduce the need for virgin plastic.
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Affiliation(s)
- Ville Lahtela
- SCI‐MAT Research Platform & Fiber Composite LaboratorySchool of Energy SystemsLappeenranta‐Lahti University of TechnologyYliopistonkatu 34LappeenrantaFI‐53851Finland
- Fiber Composite LaboratorySchool of Energy SystemsLappeenranta‐Lahti University of TechnologyYliopistonkatu 34LappeenrantaFI‐53851Finland
| | - Katriina Mielonen
- Fiber Composite LaboratorySchool of Energy SystemsLappeenranta‐Lahti University of TechnologyYliopistonkatu 34LappeenrantaFI‐53851Finland
| | - Prashant Parkar
- Fiber Composite LaboratorySchool of Energy SystemsLappeenranta‐Lahti University of TechnologyYliopistonkatu 34LappeenrantaFI‐53851Finland
| | - Timo Kärki
- Fiber Composite LaboratorySchool of Energy SystemsLappeenranta‐Lahti University of TechnologyYliopistonkatu 34LappeenrantaFI‐53851Finland
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Haghi M, Fotovat F, Yaghmaei S. Co-pyrolysis of paper-laminated phenolic printed circuit boards and calcium-based additives in fixed and fluidized bed reactors. WASTE MANAGEMENT (NEW YORK, N.Y.) 2023; 171:532-544. [PMID: 37806161 DOI: 10.1016/j.wasman.2023.09.041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 09/27/2023] [Accepted: 09/30/2023] [Indexed: 10/10/2023]
Abstract
This study compares the impact of the calcium-based additives and the pyrolyzer on the recovery and the halide content of the oil produced from the pyrolysis of paper-laminated phenolic resin printed circuit boards (FR2-PCB). The preliminary experiments showed that the maximum liquid recovery (40.6%) was achieved in a fluidized bed pyrolyzer containing a 50:50 mixture of CaO and Ca(OH)2 operating at T = 620 °C and PCB-to-additive ratio (FR2/A) = 5.4 g/g for 22 min. Extra tests were then carried out under these conditions in fixed and fluidized bed pyrolyzers to separately explore the impact of CaO, Ca(OH)2, and CaO + Ca(OH)2 on the liquid recovery (LR) and the halogen content of the non-solid products. In the fluidized bed, LR in the presence of CaO, Ca(OH)2, and CaO + Ca(OH)2 was 34.5%, 41.2%, and 38.9 wt%, respectively. The fraction of phenolic compounds in the pyrolysis oil ranged from 86% to 93%, about 1-3% higher than the corresponding values in the fixed bed. Using additives led to lower halide content in the pyrolysis oil of the fluidized bed than that of the fixed bed. However, the opposite trend was observed in the absence of additives. Regardless of the type of pyrolyzer, Ca(OH)2 was more successful than CaO in increasing LR, whereas CaO was more effective than Ca(OH)2 in pyrolysis oil dechlorination. Co-pyrolysis of FR2-PCB and CaO + Ca(OH)2 in a fluidized bed reactor was identified as a practical approach to enhance the recovery of pyrolysis oil comprising only 5% of the original halogen content of the feedstock.
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Affiliation(s)
- Mahdi Haghi
- Department of Chemical and Petroleum Engineering, Sharif University of Technology, Tehran, Iran
| | - Farzam Fotovat
- Department of Chemical and Petroleum Engineering, Sharif University of Technology, Tehran, Iran.
| | - Soheila Yaghmaei
- Department of Chemical and Petroleum Engineering, Sharif University of Technology, Tehran, Iran
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10
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Cueto J, Pérez-Martin G, Amodio L, Paniagua M, Morales G, Melero JA, Serrano DP. Upgrading of solid recovered fuel (SRF) by dechlorination and catalytic pyrolysis over nanocrystalline ZSM-5 zeolite. CHEMOSPHERE 2023; 339:139784. [PMID: 37567278 DOI: 10.1016/j.chemosphere.2023.139784] [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: 04/28/2023] [Revised: 07/20/2023] [Accepted: 08/08/2023] [Indexed: 08/13/2023]
Abstract
Globally increasing concern related to municipal solid waste generation is encouraging research efforts on developing alternative routes to valorize mixed refused wastes. In this way, catalytic pyrolysis is emerging as an interesting and efficient technology due to its great flexibility in terms of feedstock. In the current work, upgrading of a Solid Recovered Fuel (SRF) has been investigated by catalytic pyrolysis over nanocrystalline ZSM-5 zeolite (n-ZSM-5), paying special attention to dechlorination effects due to the high Cl content of the raw waste. Thus, pretreatment of the SRF by water washing and mild thermal processing allows for a significant reduction of the Cl concentration. Regarding the catalytic pyrolysis step, the best conditions correspond with a temperature of 400 °C in the catalyst bed and 0.50 catalyst/SRF mass ratio, which lead to ca. 30 wt% oil yield (rich in aromatic hydrocarbons) together with about 40 wt% gas yield (rich in C3-C4 olefins). Accordingly, these products could find use as raw chemicals or for the production of advanced fuels. In addition, zeolite reutilization has been tested for several cycles, denoting a progressive modification of the products distribution because of coke deposition. However, an almost total recovery of the n-ZSM-5 zeolite catalytic performance is achieved after regeneration by air calcination, affording the production of an oil fraction with a Cl content as low as 40 ppm.
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Affiliation(s)
- J Cueto
- Thermochemical Processes Unit, IMDEA Energy Institute, Avda. Ramón de La Sagra, 3, 28935, Móstoles, Madrid, Spain
| | - G Pérez-Martin
- Thermochemical Processes Unit, IMDEA Energy Institute, Avda. Ramón de La Sagra, 3, 28935, Móstoles, Madrid, Spain
| | - L Amodio
- Thermochemical Processes Unit, IMDEA Energy Institute, Avda. Ramón de La Sagra, 3, 28935, Móstoles, Madrid, Spain; Chemical and Environmental Engineering Group, Universidad Rey Juan Carlos, Tulipán s/n, 28933, Móstoles, Madrid, Spain
| | - M Paniagua
- Chemical and Environmental Engineering Group, Universidad Rey Juan Carlos, Tulipán s/n, 28933, Móstoles, Madrid, Spain
| | - G Morales
- Chemical and Environmental Engineering Group, Universidad Rey Juan Carlos, Tulipán s/n, 28933, Móstoles, Madrid, Spain
| | - J A Melero
- Chemical and Environmental Engineering Group, Universidad Rey Juan Carlos, Tulipán s/n, 28933, Móstoles, Madrid, Spain
| | - D P Serrano
- Thermochemical Processes Unit, IMDEA Energy Institute, Avda. Ramón de La Sagra, 3, 28935, Móstoles, Madrid, Spain; Chemical and Environmental Engineering Group, Universidad Rey Juan Carlos, Tulipán s/n, 28933, Móstoles, Madrid, Spain.
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11
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Asueta A, Fulgencio-Medrano L, Miguel-Fernández R, Leivar J, Amundarain I, Iruskieta A, Arnaiz S, Gutiérrez-Ortiz JI, Lopez-Urionabarrenechea A. A Preliminary Study on the Use of Highly Aromatic Pyrolysis Oils Coming from Plastic Waste as Alternative Liquid Fuels. MATERIALS (BASEL, SWITZERLAND) 2023; 16:6306. [PMID: 37763583 PMCID: PMC10532589 DOI: 10.3390/ma16186306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 09/14/2023] [Accepted: 09/15/2023] [Indexed: 09/29/2023]
Abstract
In this work, the low-temperature pyrolysis of a real plastic mixture sample collected at a WEEE-authorised recycling facility has been investigated. The sample was pyrolysed in a batch reactor in different temperature and residence time conditions and auto-generated pressure by following a factorial design, with the objective of maximising the liquid (oil) fraction. Furthermore, the main polymers constituting the real sample were also pyrolysed in order to understand their role in the generation of oil. The pyrolysis oils were characterised and compared with commercial fuel oil number 6. The results showed that in comparison to commercial fuel oil, pyrolysis oils coming from WEEE plastic waste had similar heating values, were lighter and less viscous and presented similar toxicity profiles in fumes of combustion.
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Affiliation(s)
- Asier Asueta
- GAIKER Technology Centre, Basque Research and Technology Alliance (BRTA), Parque Tecnológico de Bizkaia, Edificio 202, 48170 Zamudio, Spain; (A.A.)
| | - Laura Fulgencio-Medrano
- GAIKER Technology Centre, Basque Research and Technology Alliance (BRTA), Parque Tecnológico de Bizkaia, Edificio 202, 48170 Zamudio, Spain; (A.A.)
| | - Rafael Miguel-Fernández
- GAIKER Technology Centre, Basque Research and Technology Alliance (BRTA), Parque Tecnológico de Bizkaia, Edificio 202, 48170 Zamudio, Spain; (A.A.)
| | - Jon Leivar
- GAIKER Technology Centre, Basque Research and Technology Alliance (BRTA), Parque Tecnológico de Bizkaia, Edificio 202, 48170 Zamudio, Spain; (A.A.)
| | - Izotz Amundarain
- GAIKER Technology Centre, Basque Research and Technology Alliance (BRTA), Parque Tecnológico de Bizkaia, Edificio 202, 48170 Zamudio, Spain; (A.A.)
| | - Ana Iruskieta
- GAIKER Technology Centre, Basque Research and Technology Alliance (BRTA), Parque Tecnológico de Bizkaia, Edificio 202, 48170 Zamudio, Spain; (A.A.)
| | - Sixto Arnaiz
- GAIKER Technology Centre, Basque Research and Technology Alliance (BRTA), Parque Tecnológico de Bizkaia, Edificio 202, 48170 Zamudio, Spain; (A.A.)
| | - Jose Ignacio Gutiérrez-Ortiz
- Chemical Engineering Department, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), 48940 Leioa, Spain
| | - Alexander Lopez-Urionabarrenechea
- Chemical and Environmental Engineering Department, Faculty of Engineering of Bilbao, University of the Basque Country (UPV/EHU), Plaza Ingeniero Torres Quevedo 1, 48013 Bilbao, Spain
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12
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Kuttiyathil MS, Ali L, Ahmed OH, Altarawneh M. Combating toxic emissions from thermal recycling of polymeric fractions laden with novel brominated flame retardants (NBFRs) in e-waste: an in-situ approach using Ca(OH) 2. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:98300-98313. [PMID: 37606772 DOI: 10.1007/s11356-023-29428-2] [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: 05/29/2023] [Accepted: 08/17/2023] [Indexed: 08/23/2023]
Abstract
Legacy brominated flame retardants (BFRs) in printed circuit boards are gradually being replaced by novel BFRs (NBFRs). Safe disposal and recycling of polymeric constituents in the polymeric fractions of e-waste necessitate the removal of their toxic and corrosive bromine content. This is currently acquired through thermal recycling operations involving the pyrolysis of BFRs-containing materials with metal oxides. Nonetheless, the debromination capacity toward NBFRs is yet to be established. Thus, this study aims to address these two crucial gaps in the current knowledge pertaining to the plausible formation of brominated toxicants from the thermal decomposition of NBFRs and their thermal recycling potential. Herein, we investigate the pyrolysis of a mixture of 2,4,6-tribromophenol (TBP), allyl 2,4,6-tribromophenyl ether (ATE) and Tetrabromobisphenol A-bis (2,3-dibromo propyl ether) (TBBPA-DBPE) in the presence of acrylonitrile butadiene styrene (ABS) polymers at various loads. To demonstrate a viable debromination route, pyrolysis of NBFRs-ABS mixture with Ca(OH)2 was also investigated. The latter is a potent debromination agent for legacy BFRs. Upon pyrolysis with Ca(OH)2, the bromine content in the collected oil was reduced up to 80.49% between 25-500 °C. Products of the co-pyrolysis process generally feature non-brominated aromatic and aliphatic compounds; a finding that indicates an effective thermal recycling approach. As evident by IC measurements, no HBr emission could be detected when Ca(OH)2 is added to the mixture. As XRD patterns show, Ca(OH)2 is partially converted into CaBr2. DFT calculations provide pathways for the observed surface debromination characterized by surface-assisted fission of aromatic C-Br bonds and the formation of CaBr sites. Outcomes reported herein are instrumental to designing and operating a thermal recycling facility of polymeric materials contaminated with high loads of bromine, i.e., most notably during scenarios encountered in the thermal recycling of e-waste.
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Affiliation(s)
- Mohamed Shafi Kuttiyathil
- Department of Chemical and Petroleum Engineering, United Arab Emirates University, Sheikh Khalifa Bin Zayed Street, 15551, Al-Ain, United Arab Emirates
| | - Labeeb Ali
- Department of Chemical and Petroleum Engineering, United Arab Emirates University, Sheikh Khalifa Bin Zayed Street, 15551, Al-Ain, United Arab Emirates
| | - Oday H Ahmed
- Department of Physics, College of Education, Al- Iraqia University, Baghdad, Iraq
| | - Mohammednoor Altarawneh
- Department of Chemical and Petroleum Engineering, United Arab Emirates University, Sheikh Khalifa Bin Zayed Street, 15551, Al-Ain, United Arab Emirates.
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13
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Debromination of Waste Circuit Boards by Reaction in Solid and Liquid Phases: Phenomenological Behavior and Kinetics. Polymers (Basel) 2023; 15:polym15061388. [PMID: 36987169 PMCID: PMC10052934 DOI: 10.3390/polym15061388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 03/01/2023] [Accepted: 03/08/2023] [Indexed: 03/12/2023] Open
Abstract
The debromination of waste circuit boards (WCBs) used in computer motherboards and components has been studied with two different pieces of equipment. Firstly, the reaction of small particles (around one millimeter in diameter) and larger pieces obtained from WCBs was carried out with several solutions of K2CO3 in small non-stirred batch reactors at 200–225 °C. The kinetics of this heterogeneous reaction has been studied considering both the mass transfer and chemical reaction steps, concluding that the chemical step is much slower than diffusion. Additionally, similar WCBs were debrominated using a planetary ball mill and solid reactants, namely calcined CaO, marble sludge, and calcined marble sludge. A kinetic model has been applied to this reaction, finding that an exponential model is able to explain the results quite satisfactorily. The activity of the marble sludge is about 13% of that of pure CaO and is increased to 29% when slightly calcinating its calcite at only 800 °C for 2 h.
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14
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Li C, Xia H, Liu C, Zeng K, Zhang L. Analysis of the effect of heating rate on pyrolysis kinetics and product composition of copper-containing waste circuit boards. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:33075-33089. [PMID: 36471150 DOI: 10.1007/s11356-022-24524-1] [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: 09/06/2022] [Accepted: 11/28/2022] [Indexed: 06/17/2023]
Abstract
Pyrolysis is a cost-effective and environmentally benign method for recycling organic waste, which can be converted into high-energy gases and oils. Pyrolysis technology was employed in this study to recycle copper-containing discarded circuit board material and recover copper, glass fibers, and gases and oils with high calorific values. Thermogravimetric analyses (TGA), Fourier transform infrared spectroscopy (FTIR), and gas chromatography-mass spectrometry (GC-MS) were used to evaluate pyrolyses of copper-containing waste circuit board materials conducted at different heating rates (5, 10, 20, and 40 °C/min), and the resulting volatiles were studied in detail. The effects of heating rate on the kinetics and activation energies for pyrolyses of copper-containing waste circuit boards were also investigated by using the Coats-Redfern (C-R) method. The TGA curves and FTIR spectra did not differ significantly for different heating rates, and the main functional groups identified with the FTIR results were O-H, C = C, aromatic benzene, substituted benzene, and C-Br. Additionally, GC-MS analyses showed that the heating rate had a great influence on the pyrolysis products formed; the phenol content decreased with increasing heating rate, and the highest content was realized at 5 ℃/min. Energy dispersive spectroscopy (EDS) analyses showed that bromine was removed from the solid phase products during pyrolysis, while copper was effectively enriched in the feedstock. This indicated that pyrolysis can be used to recover copper-containing waste circuit boards.
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Affiliation(s)
- Chunyu Li
- Faculty of Metallurgy and Energy Engineering, Kunming University of Science and Technology, Kunming, 650093, Yunnan, China
- Yunnan Provincial Key Laboratory of Intensification Metallurgy, Kunming University of Science and Technology, Kunming, 650093, Yunnan, China
- Key Laboratory of Unconventional Metallurgy, Ministry of Education, Kunming, 650093, Yunnan, China
- State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Kunming University of Science and Technology, Kunming, 650093, Yunnan, China
| | - Hongying Xia
- Faculty of Metallurgy and Energy Engineering, Kunming University of Science and Technology, Kunming, 650093, Yunnan, China.
- Yunnan Provincial Key Laboratory of Intensification Metallurgy, Kunming University of Science and Technology, Kunming, 650093, Yunnan, China.
- Key Laboratory of Unconventional Metallurgy, Ministry of Education, Kunming, 650093, Yunnan, China.
- State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Kunming University of Science and Technology, Kunming, 650093, Yunnan, China.
| | - Chengfei Liu
- Faculty of Metallurgy and Energy Engineering, Kunming University of Science and Technology, Kunming, 650093, Yunnan, China
- Yunnan Copper Co., Ltd, Kunming, 650000, China
| | - Kangqing Zeng
- Faculty of Metallurgy and Energy Engineering, Kunming University of Science and Technology, Kunming, 650093, Yunnan, China
- Yunnan Provincial Key Laboratory of Intensification Metallurgy, Kunming University of Science and Technology, Kunming, 650093, Yunnan, China
- Key Laboratory of Unconventional Metallurgy, Ministry of Education, Kunming, 650093, Yunnan, China
- State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Kunming University of Science and Technology, Kunming, 650093, Yunnan, China
| | - Libo Zhang
- Faculty of Metallurgy and Energy Engineering, Kunming University of Science and Technology, Kunming, 650093, Yunnan, China
- Yunnan Provincial Key Laboratory of Intensification Metallurgy, Kunming University of Science and Technology, Kunming, 650093, Yunnan, China
- Key Laboratory of Unconventional Metallurgy, Ministry of Education, Kunming, 650093, Yunnan, China
- State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Kunming University of Science and Technology, Kunming, 650093, Yunnan, China
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15
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Alaedini AH, Tourani HK, Saidi M. A review of waste-to-hydrogen conversion technologies for solid oxide fuel cell (SOFC) applications: Aspect of gasification process and catalyst development. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 329:117077. [PMID: 36565498 DOI: 10.1016/j.jenvman.2022.117077] [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: 10/06/2022] [Revised: 12/12/2022] [Accepted: 12/17/2022] [Indexed: 06/17/2023]
Abstract
In the twenty-first century, there has been an increase in energy demand and waste production, due to the rising population of the world. One good approach for satisfying the energy demand and overcoming the waste management issues is to convert waste to energy. Additionally, using waste biomass as the feedstock of waste-to-energy (WtE) conversion methods makes them renewable and green and also helps the environmental challenges and reduces the emission of greenhouse gases (GHGs). Gasification is a thermochemical WtE route, which can produce hydrogen-rich gaseous biofuel called synthetic gas (syngas), from wastes. In this paper, different aspects of gasification process are reviewed with greater focus on catalyst usage. Syngas processing steps, which increase the quality and H2 content of the syngas to form bio-hydrogen, are discussed. Solid oxide fuel cell (SOFC) technology is one of the most promising techniques of renewable energy production due to their environmental cleanness characteristics and high efficiencies. Thus, one of the best ways to exploit the energy content of the bio-hydrogen product of gasification is to employ it in a SOFC. Therefore, waste biomass gasification process can be integrated with SOFCs to build high efficiency systems for production of clean and renewable energy from waste, which are called integrated gasification fuel cell (IGFC) systems. These systems provide the opportunity of further upgrading of syngas inside the SOFC. In this paper, we are going to briefly discuss fuel cell technology (especially SOFCs) and review SOFC applications from the aspect of integration with gasification process (IGFC system). Finally, the impacts and issues of gasification process and SOFC technology are considered.
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Affiliation(s)
- Amir Hossein Alaedini
- School of Chemistry, College of Science, University of Tehran, 14155-6455, Tehran, Iran
| | | | - Majid Saidi
- School of Chemistry, College of Science, University of Tehran, 14155-6455, Tehran, Iran.
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16
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Removal of Bromine from Polymer Blends with a Composition Simulating That Found in Waste Electric and Electronic Equipment through a Facile and Environmentally Friendly Method. Polymers (Basel) 2023; 15:polym15030709. [PMID: 36772010 PMCID: PMC9919020 DOI: 10.3390/polym15030709] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 01/16/2023] [Accepted: 01/26/2023] [Indexed: 02/01/2023] Open
Abstract
The increasing volume of plastics from waste electric and electronic equipment (WEEE) nowadays is of major concern since the various toxic compounds that are formed during their handling enhance the difficulties in recycling them. To overcome these problems, this work examines solvent extraction as a pretreatment method, prior to thermochemical recycling by pyrolysis. The aim is to remove bromine from some polymeric blends, with a composition that simulates WEEE, in the presence of tetrabromobisphenol A (TBBPA). Various solvents-isopropanol, ethanol and butanol-as well as several extraction times, were investigated in order to find the optimal choice. Before and after the pretreatment, blends were analysed by X-ray fluorescence (XRF) to estimate the total bromine content. Blends were pyrolyzed before and after the soxhlet extraction in order to evaluate the derived products. FTIR measurements of the polymeric blends before and after the soxhlet extraction showed that their structure was maintained. From the results obtained, it was indicated that the reduction of bromine was achieved in all cases tested and it was ~34% for blend I and ~46% and 42% for blend II when applying a 6 h soxhlet with isopropanol and ethanol, respectively. When using butanol bromine was completely eliminated, since the reduction reached almost 100%. The latter finding is of great importance, since the complete removal of bromine enables the recycling of pure plastics. Therefore, the main contribution of this work to the advancement of knowledge lies in the use of a solvent (i.e., butanol) which is environmentally friendly and with a high dissolving capacity in brominated compounds, which can be used in a pretreatment stage of plastic wastes before it is recycled by pyrolysis.
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17
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Wang Y, Huang J, Wang H, Lan L, Mu X, Xu W, Lv S, Li X. Theoretical study on pyrolysis mechanism of decabromodiphenyl ether (BDE-209) using DFT method. CHEMOSPHERE 2023; 310:136904. [PMID: 36265714 DOI: 10.1016/j.chemosphere.2022.136904] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Revised: 10/12/2022] [Accepted: 10/13/2022] [Indexed: 06/16/2023]
Abstract
Decabromodiphenyl ether (BDE-209), as a brominated flame retardant (BFR), is widely applied to various consumer products due to its superior performance and affordable pricing to improve the flame resistance of materials. To better comprehend the pyrolysis behavior of BDE-209 and the evolution process of main pyrolysis products, the thermal degradation mechanism of BDE-209 was studied using density functional theory (DFT) method at the theoretical level of M06/cc-pVDZ, and thermodynamic parameters were calculated in this paper. Unimolecular degradation was dominated by cleavage of the ether linkage, which results in a high yield of hexabromobenzene, and fission of the ortho-position C-Br bond is the main competitive reaction channel. In the system of BDE-209 + H, the pyrolysis reaction is majorly characterized by debromination, leading to the formation of considerable HBr and low-brominated diphenyl ethers. Additionally, the hydrogen-derived splitting of the ether bond acts as a mainly competitive channel, which is the source of polybromophenols and polybromobenzenes. The formation of polybrominated dibenzofuran (PBDF) derives from the cyclization reaction of ortho-phenyl-type radicals, which are readily generated through the ortho-position Br atom abstraction by H radical. The formation of polybrominated dibenzo-p-dioxin (PBDD) involves the ortho-C-O coupling reaction of polybromophenoxy radicals, debromination reaction, and cyclization reaction. And the total yield of PBDD/Fs was significantly increased when H was involved. Results presented in this work will provide the helpful information for the treatment and reuse of BDE-209-containing waste plastics through using pyrolysis technology.
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Affiliation(s)
- Yao Wang
- School of Mechatronics Engineering, Guizhou Minzu University, Guiyang, 550025, China
| | - Jinbao Huang
- School of Mechatronics Engineering, Guizhou Minzu University, Guiyang, 550025, China.
| | - Hong Wang
- School of Mechatronics Engineering, Guizhou Minzu University, Guiyang, 550025, China
| | - Lin Lan
- School of Mechatronics Engineering, Guizhou Minzu University, Guiyang, 550025, China
| | - Xin Mu
- School of Mechatronics Engineering, Guizhou Minzu University, Guiyang, 550025, China
| | - Weiwei Xu
- School of Mechatronics Engineering, Guizhou Minzu University, Guiyang, 550025, China
| | - Shanjin Lv
- School of Mechatronics Engineering, Guizhou Minzu University, Guiyang, 550025, China
| | - Xinsheng Li
- School of Resources, Environment and Materials, Guangxi University, Nanning, 530004, China.
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Wang Z, Praetorius A. Integrating a Chemicals Perspective into the Global Plastic Treaty. ENVIRONMENTAL SCIENCE & TECHNOLOGY LETTERS 2022; 9:1000-1006. [PMID: 36530847 PMCID: PMC9753957 DOI: 10.1021/acs.estlett.2c00763] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 11/11/2022] [Accepted: 11/15/2022] [Indexed: 06/01/2023]
Abstract
Driven by the growing concern about plastic pollution, countries have agreed to establish a global plastic treaty addressing the full life cycle of plastics. However, while plastics are complex materials consisting of mixtures of chemicals such as additives, processing aids, and nonintentionally added substances, it is at risk that the chemical aspects of plastics may be overlooked in the forthcoming treaty. This is highly concerning because a large variety of over 10,000 chemical substances may have been used in plastic production, and many of them are known to be hazardous to human health and the environment. In this Global Perspective, we further highlight an additional, generally overlooked, but critical aspect that many chemicals in plastics hamper the technological solutions envisioned to solve some of the major plastic issues: mechanical recycling, waste-to-energy, chemical recycling, biobased plastics, biodegradable plastics, and durable plastics. Building on existing success stories, we outline three concrete recommendations on how the chemical aspects can be integrated into the global plastic treaty to ensure its effectiveness: (1) reducing the complexity of chemicals in plastics, (2) ensuring the transparency of chemicals in plastics, and (3) aligning the right incentives for a systematic transition.
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Affiliation(s)
- Zhanyun Wang
- Empa
− Swiss Federal Laboratories for Materials Science and Technology,
Technology and Society Laboratory, 9014 St. Gallen, Switzerland
| | - Antonia Praetorius
- Institute
for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam 1090, GE, Netherlands
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Sikander A, Kelly S, Kuchta K, Sievers A, Willner T, Hursthouse AS. Chemical and Microbial Leaching of Valuable Metals from PCBs and Tantalum Capacitors of Spent Mobile Phones. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph191610006. [PMID: 36011640 PMCID: PMC9408593 DOI: 10.3390/ijerph191610006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 08/01/2022] [Accepted: 08/11/2022] [Indexed: 05/25/2023]
Abstract
We compared chemical and microbial leaching for multi-metal extraction from printed circuit boards (PCBs) and tantalum capacitor scrap. A mixed consortium of acidophiles and heterotrophic fungal strains were used in the experiments and compared to chemical leaching using specific acids (sulfuric, citric and oxalic acids). Under optimum conditions, 100% extraction efficiency of Cu, and nearly 85% of Zn, Fe, Al and Ni were achieved from PCB and tantalum capacitor scrap samples using sulfuric acid. The mixed consortium of acidophiles successfully mobilized, Ni and Cu (99% and 96%, respectively) while Fe, Zn, Al and Mn reached an extraction yield of 89, 77, 70 and 43%, respectively, from the PCB samples. For the tantalum capacitor samples, acidophiles mobilized 92% Cu, 88% Ni, 78% Fe, 77% Al, 70% Zn and 57% Mn. Metal mobilization from PCBs and tantalum capacitor scrap by A. niger filtrate showed efficient solubilization of Cu, Fe, Al, Mn, Ni, Pb and Zn at an efficiency of 52, 29, 75, 5, 61, 21 and 35% from PCB samples and 61, 25, 69, 23, 68, 15 and 45% from tantalum capacitor samples, respectively. Microbial leaching proved viable as a method to extract base metals but was less specific for tantalum and precious metals in electronic waste. The implications of these results for further processing of waste electronic and electrical equipment (WEEE) are considered in potential hybrid treatment strategies.
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Affiliation(s)
- Asma Sikander
- Department of Process Engineering, Hamburg University of Applied Sciences, Ulmenliet 20, 21033 Hamburg, Germany
- School of Computing, Engineering & Physical Sciences, University of the West of the Scotland, Scotland PA1 2BE, UK
| | - Steven Kelly
- School of Health Life Sciences, University of the West of Scotland, Scotland G72 0LH, UK
| | - Kerstin Kuchta
- Institute for Environmental Engineering and Energy Economics, TUHH—Hamburg University of Technology, 21079 Hamburg, Germany
| | - Anika Sievers
- Department of Process Engineering, Hamburg University of Applied Sciences, Ulmenliet 20, 21033 Hamburg, Germany
| | - Thomas Willner
- Department of Process Engineering, Hamburg University of Applied Sciences, Ulmenliet 20, 21033 Hamburg, Germany
| | - Andrew S. Hursthouse
- School of Computing, Engineering & Physical Sciences, University of the West of the Scotland, Scotland PA1 2BE, UK
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20
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Guo X, Peng S, Jiang L, Mo X, Zhu Y, Liu Y, Cai K, Song Q. Removal of polybrominated diphenyl ethers in high impact polystyrene (HIPS) from waste TV sets. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:59317-59327. [PMID: 35384541 DOI: 10.1007/s11356-022-20046-y] [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: 11/30/2021] [Accepted: 03/29/2022] [Indexed: 06/14/2023]
Abstract
Most studies have shown that improper disposal of e-waste can accelerate the release of high concentrations of polybrominated diphenyl ethers (PBDEs), and this situation causes environmental pollution and human health risks. The recycling technology of waste electronic plastics based on solvent processes can reduce environmental pollution and health risks from PBDEs. In this study, high impact polystyrene (HIPS) from waste TV sets was taken as the research object, and d-limonene and n-propanol were used as solvent and precipitant, respectively. We studied the relationship between the precipitation conditions and the size of precipitate particles, and the effect laws of precipitation conditions on the removal percentage of PBDEs were discussed. Transferring behavior of PBDEs during precipitation was investigated, and the parameters suitable for removing PBDEs from HIPS solution were confirmed. Results showed that lower HIPS concentration in d-limonene, lower precipitation temperature, higher mass ratio of n-propanol to HIPS solution, and greater stirring speed were conducive to form smaller and more uniform precipitate particles. All conditions (concentration, temperature, mass ratio, and stirring rate) that could increase the solubility of PBDEs in the mixed solvent of limonene and n-propanol or decrease the swelling degree of HIPS precipitate particles, or reduce the size of particles could improve the removal percentage of PBDEs. The investigated results indicated that insoluble PBDEs (e.g., decabromodiphenyl ether) transferred into the HIPS precipitate mainly through the generated crystals and then precipitated together with the HIPS particles, and soluble PBDEs (e.g., octabromodiphenyl ether) migrated into the precipitate by the solution entrained. The precipitate particles, which measured approximately 1.0 mm (on average), were obtained when the solution containing 10% of HIPS from waste TV shell was precipitated by adding n-propanol equivalent to twice the mass of the solution at 40 °C and 3000 r/min stirring speed. The total concentration of PBDEs in the precipitate particles (dried) was reduced to 2369 mg/kg, and 88.06% of the PBDEs in the original plastic solution was successfully removed by this process.
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Affiliation(s)
- Xinran Guo
- Guangdong Provincial Key Laboratory of Petrochemical Pollution Process and Control, Maoming, 525000, Guangdong, China
- School of Environmental Science and Engineering, Guangdong University of Petrochemical Technology, Maoming, 52500, China
| | - Shaohong Peng
- Guangdong Provincial Key Laboratory of Petrochemical Pollution Process and Control, Maoming, 525000, Guangdong, China.
- School of Material Science and Engineering, Guangdong University of Petrochemical Technology, Maoming, 525000, Guangdong, China.
| | - Liwang Jiang
- School of Material Science and Engineering, Guangdong University of Petrochemical Technology, Maoming, 525000, Guangdong, China
| | - Xiaoning Mo
- School of Environmental Science and Engineering, Guangdong University of Petrochemical Technology, Maoming, 52500, China
| | - Yunhong Zhu
- School of Environmental Science and Engineering, Guangdong University of Petrochemical Technology, Maoming, 52500, China
| | - Yang Liu
- School of Environmental Science and Engineering, Guangdong University of Petrochemical Technology, Maoming, 52500, China
| | - Kaihan Cai
- Macao Environmental Research Institute, Macau University of Science and Technology, Macao, 999078, China
| | - Qingbin Song
- Macao Environmental Research Institute, Macau University of Science and Technology, Macao, 999078, China
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21
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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: 12] [Impact Index Per Article: 6.0] [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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22
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Advancements in the field of electronic waste Recycling: Critical assessment of chemical route for generation of energy and valuable products coupled with metal recovery. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2022.120773] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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23
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Recent Advances in the Decontamination and Upgrading of Waste Plastic Pyrolysis Products: An Overview. Processes (Basel) 2022. [DOI: 10.3390/pr10040733] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Extensive research on the production of energy and valuable materials from plastic waste using pyrolysis has been widely conducted during recent years. Succeeding in demonstrating the sustainability of this technology economically and technologically at an industrial scale is a great challenge. In most cases, crude pyrolysis products cannot be used directly for several reasons, including the presence of contaminants. This is confirmed by recent studies, using advanced characterization techniques such as two-dimensional gas chromatography. Thus, to overcome these limitations, post-treatment methods, such as dechlorination, distillation, catalytic upgrading and hydroprocessing, are required. Moreover, the integration of pyrolysis units into conventional refineries is only possible if the waste plastic is pre-treated, which involves sorting, washing and dehalogenation. The different studies examined in this review showed that the distillation of plastic pyrolysis oil allows the control of the carbon distribution of different fractions. The hydroprocessing of pyrolytic oil gives promising results in terms of reducing contaminants, such as chlorine, by one order of magnitude. Recent developments in plastic waste and pyrolysis product characterization methods are also reported in this review. The application of pyrolysis for energy generation or added-value material production determines the economic sustainability of the process.
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24
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Charitopoulou MA, Papadopoulou L, Achilias DS. Effect of brominated flame retardant on the pyrolysis products of polymers originating in WEEE. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:29570-29582. [PMID: 34312751 DOI: 10.1007/s11356-021-15489-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Accepted: 07/13/2021] [Indexed: 06/13/2023]
Abstract
Chemical recycling is an environmentally friendly method, which is often used for the recycling of plastics included in waste electric and electronic equipment (WEEE), since fuels and secondary valuable materials can be produced. Brominated flame retardants (BFRs) are usually added into these plastics to reduce their flammability; but they are toxic substances. The aim of this work is to examine the thermal behaviour and the products obtained after pyrolysis of polymer blends that consist of acrylonitrile-butadiene-styrene (ABS), high-impact polystyrene (HIPS), polycarbonate (PC) and polypropylene (PP) with composition that simulates real WEEE, in the absence and presence of a common BFR, tetrabromobisphenol A (TBBPA), in order to investigate its effect on pyrolysis products. Blends were prepared via the solvent casting method and the melt-mixing in an extruder; it was revealed that the latter method may be a better choice for blends preparation, since it did not affect the products obtained. The chemical structure of each polymeric blend was identified by Fourier transform infrared spectroscopy (FTIR). Thermal degradation of the blends was evaluated by thermogravimetric (TG) experiments performed using a thermal analyser (TGA) and a pyrolyser for evolved gas analysis (EGA). It was observed that blends had a similar behaviour during their thermal degradation; and in most cases, they followed a one-step mechanism. Pyrolysis products were identified by the pyrolyser combined with a gas chromatographer/mass spectrometer (GC/MS), and comprised various useful compounds, such as monomers, aromatic hydrocarbons and phenolic compounds that could be used as chemical feedstock. Furthermore, it was found that TBBPA affected products distribution by enhancing the formation of phenolic compounds and on the other hand by resulting in brominated compounds, such as dibromophenol.
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Affiliation(s)
- Maria Anna Charitopoulou
- Laboratory of Polymers and Dyes Chemistry and Technology, Department of Chemistry, Aristotle University of Thessaloniki, 541 24, Thessaloniki, Greece
| | - Lambrini Papadopoulou
- Department of Mineralogy-Petrology-Economic Geology, Aristotle University of Thessaloniki, GR-54 124, Thessaloniki, Greece
| | - Dimitriοs S Achilias
- Laboratory of Polymers and Dyes Chemistry and Technology, Department of Chemistry, Aristotle University of Thessaloniki, 541 24, Thessaloniki, Greece.
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25
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26
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Zhu P, Shen Y, Li X, Liu X, Qian G, Zhou J. Feeding preference of insect larvae to waste electrical and electronic equipment plastics. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 807:151037. [PMID: 34666086 DOI: 10.1016/j.scitotenv.2021.151037] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 09/27/2021] [Accepted: 10/13/2021] [Indexed: 06/13/2023]
Abstract
Waste electrical and electronic equipment (WEEE) plastics not only pollute the environment, but are challenging to treat in an environmentally friendly manner. Biodegradation by insect larvae is potentially an eco-friendly method to treat WEEE plastics, but information about the feeding preference of insect larvae to WEEE plastics is lacking. In this study, a total of nine WEEE and pristine plastics were chosen to feed larvae of the following two insect species, i.e. Galleria mellonella and Tenebrio molitor. G. mellonella larvae significantly favor corresponding pristine plastics compared to two types of WEEE plastics, waste rigid polyurethane (RPU) and waste polystyrene (PS). One possible explanation is the increased chlorine or metals in the WEEE plastics measured using X-ray fluorescence spectrometer analysis. Scanning electron microscopy and Fourier transform infrared spectroscopy show that the destruction of physical structures and changes in surface functional groups were found in the two types of WEEE plastics in the larval frass, implying that the larvae partly biodegraded the plastics. Meanwhile, the powdered waste high impact polystyrene plastics (WHIPS) were ingested, but not the lumpy ones, indicating that the consumption by G. mellonella larvae is improved by the WHIPS physical modification. In addition, G. mellonella larvae presented the following decreasing preference for pristine plastics under individual-plastic-fed mode: RPU > phenol-formaldehyde resin > polyethylene (PE) > polypropylene > PS ≈ polyvinyl chloride; this is possibly due to differences in physical properties and chemical structures of the plastics; feeding preference of the larvae under multiple-plastics-fed mode is relatively consistent to that under individual-plastic-fed mode. Interestingly, the consumption by G. mellonella larvae of PE is higher than that of PS, while T. molitor larvae showed the opposite trend, implying that insect larvae have different plastics preference. The findings provide insights into biodegradation of WEEE plastics by insect larvae.
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Affiliation(s)
- Ping Zhu
- School of Environmental and Chemical Engineering, Shanghai University, 99 Shangda Road, Shanghai 200444, People's Republic of China
| | - Yilin Shen
- School of Environmental and Chemical Engineering, Shanghai University, 99 Shangda Road, Shanghai 200444, People's Republic of China
| | - Xiaowei Li
- School of Environmental and Chemical Engineering, Shanghai University, 99 Shangda Road, Shanghai 200444, People's Republic of China.
| | - Xiankai Liu
- School of Environmental and Chemical Engineering, Shanghai University, 99 Shangda Road, Shanghai 200444, People's Republic of China
| | - Guangren Qian
- School of Environmental and Chemical Engineering, Shanghai University, 99 Shangda Road, Shanghai 200444, People's Republic of China
| | - John Zhou
- School of Civil and Environmental Engineering, University of Technology Sydney, 15 Broadway, Sydney, NSW 2007, Australia
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27
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Kusenberg M, Eschenbacher A, Djokic MR, Zayoud A, Ragaert K, De Meester S, Van Geem KM. Opportunities and challenges for the application of post-consumer plastic waste pyrolysis oils as steam cracker feedstocks: To decontaminate or not to decontaminate? WASTE MANAGEMENT (NEW YORK, N.Y.) 2022; 138:83-115. [PMID: 34871884 PMCID: PMC8769047 DOI: 10.1016/j.wasman.2021.11.009] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 10/11/2021] [Accepted: 11/07/2021] [Indexed: 05/15/2023]
Abstract
Thermochemical recycling of plastic waste to base chemicals via pyrolysis followed by a minimal amount of upgrading and steam cracking is expected to be the dominant chemical recycling technology in the coming decade. However, there are substantial safety and operational risks when using plastic waste pyrolysis oils instead of conventional fossil-based feedstocks. This is due to the fact that plastic waste pyrolysis oils contain a vast amount of contaminants which are the main drivers for corrosion, fouling and downstream catalyst poisoning in industrial steam cracking plants. Contaminants are therefore crucial to evaluate the steam cracking feasibility of these alternative feedstocks. Indeed, current plastic waste pyrolysis oils exceed typical feedstock specifications for numerous known contaminants, e.g. nitrogen (∼1650 vs. 100 ppm max.), oxygen (∼1250 vs. 100 ppm max.), chlorine (∼1460vs. 3 ppm max.), iron (∼33 vs. 0.001 ppm max.), sodium (∼0.8 vs. 0.125 ppm max.)and calcium (∼17vs. 0.5 ppm max.). Pyrolysis oils produced from post-consumer plastic waste can only meet the current specifications set for industrial steam cracker feedstocks if they are upgraded, with hydrogen based technologies being the most effective, in combination with an effective pre-treatment of the plastic waste such as dehalogenation. Moreover, steam crackers are reliant on a stable and predictable feedstock quality and quantity representing a challenge with plastic waste being largely influenced by consumer behavior, seasonal changes and local sorting efficiencies. Nevertheless, with standardization of sorting plants this is expected to become less problematic in the coming decade.
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Affiliation(s)
- Marvin Kusenberg
- Laboratory for Chemical Technology (LCT), Department of Materials, Textiles and Chemical Engineering, Faculty of Engineering & Architecture, Ghent University, B-9052 Zwijnaarde, Belgium
| | - Andreas Eschenbacher
- Laboratory for Chemical Technology (LCT), Department of Materials, Textiles and Chemical Engineering, Faculty of Engineering & Architecture, Ghent University, B-9052 Zwijnaarde, Belgium
| | - Marko R Djokic
- Laboratory for Chemical Technology (LCT), Department of Materials, Textiles and Chemical Engineering, Faculty of Engineering & Architecture, Ghent University, B-9052 Zwijnaarde, Belgium
| | - Azd Zayoud
- Laboratory for Chemical Technology (LCT), Department of Materials, Textiles and Chemical Engineering, Faculty of Engineering & Architecture, Ghent University, B-9052 Zwijnaarde, Belgium
| | - Kim Ragaert
- Center for Polymer and Material Technologies (CPMT), Department of Materials, Textiles and Chemical Engineering, Faculty of Engineering and Architecture, Ghent University, B-9052 Zwijnaarde, Belgium
| | - Steven De Meester
- Laboratory for Circular Process Engineering (LCPE), Department of Green Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University, B-8500 Kortrijk, Belgium
| | - Kevin M Van Geem
- Laboratory for Chemical Technology (LCT), Department of Materials, Textiles and Chemical Engineering, Faculty of Engineering & Architecture, Ghent University, B-9052 Zwijnaarde, Belgium
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28
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Pan J, Jiang H, Qing T, Zhang J, Tian K. Transformation and kinetics of chlorine-containing products during pyrolysis of plastic wastes. CHEMOSPHERE 2021; 284:131348. [PMID: 34214932 DOI: 10.1016/j.chemosphere.2021.131348] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 06/18/2021] [Accepted: 06/25/2021] [Indexed: 06/13/2023]
Abstract
Pyrolysis can not only effectively dispose of plastic wastes but also reclaim valuable chemicals and biochar. However, the production and release of second pollutants, particularly chlorine-containing products, have been neglected. The mechanism for the transformation of chlorine during the pyrolysis of plastic wastes remains unclear. Herein, a thermogravimetric Fourier transform infrared mass spectrometry technology was used to investigate the migration and transformation of substances during the pyrolysis of polyvinyl chloride (PVC) plastic from 200 °C to 900 °C with heating rates of 5, 50, 100, 150, and 200 K min-1. Results show the first stage of weight loss is at 200 °C-360 °C, where the dehydrochlorination of PVC mainly occurred, accompanied by the formation of conjugated double bonds and a small number of hydrocarbon compounds. The second stage of weight loss is at 360 °C-550 °C, where the breakage and rearrangement of the long polyethene chain may occur. Kinetics analysis shows the higher activation energy value is in the second stage, which indicates that the second stage reaction is less likely to occur and the Flynn-Wall-Ozawa method is more suitable for the study of plastic pyrolysis kinetics. This study suggests that second pollutants can be minimized during controllable pyrolysis.
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Affiliation(s)
- Jing Pan
- Xiangtan University School of Environment and Resources, Xiangtan University, Xiangtan, 411100, China
| | - Hong Jiang
- Key Laboratory of Urban Pollutant Conversion, Department of Applied Chemistry, University of Science and Technology of China, Hefei, 230026, China
| | - Taiping Qing
- Xiangtan University School of Environment and Resources, Xiangtan University, Xiangtan, 411100, China
| | - Junfeng Zhang
- Xiangtan University School of Environment and Resources, Xiangtan University, Xiangtan, 411100, China
| | - Ke Tian
- Xiangtan University School of Environment and Resources, Xiangtan University, Xiangtan, 411100, China.
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29
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Huang J, Mu X, Luo X, Meng H, Wang H, Jin L, Li X, Lai B. DFT studies on pyrolysis mechanisms of tetrabromobisphenol A (TBBPA). ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:68817-68833. [PMID: 34282544 DOI: 10.1007/s11356-021-15426-9] [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: 04/17/2021] [Accepted: 07/08/2021] [Indexed: 06/13/2023]
Abstract
Tetrabromobisphenol A (TBBPA) is the most widely used brominated flame retardant. In order to better understand the decomposition process of TBBPA and clarify the evolution process of the main pyrolysis products, the density functional theory (DFT) method PBE0/6-311G(d) has been used to investigate the pyrolysis mechanisms of TBBPA in this study. Seven possible pyrolysis reaction paths were proposed, and the kinetic parameters in all pyrolysis paths were calculated. The calculation results indicate that in initial degradation of TBBPA without the involvement of hydrogen radical, the demethylation reaction is the main pyrolysis reaction channel, and the keto-enol tautomerization reaction is the main competitive pyrolysis reaction channel. The brominated cyclohexadienone formed through the keto-enol tautomerization is prone to further debromination to generate Br radical. The involvement of hydrogen radical significantly lowers the energy barrier of TBBPA decomposition. When a hydrogen radical is involved in the pyrolysis process, the debromination reaction becomes the major pyrolysis reaction channel, and the homolytic cleavage of Caromatic-C bond becomes the major competitive pyrolysis reaction channel.
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Affiliation(s)
- Jinbao Huang
- School of Mechatronics Engineering, Guizhou Minzu University, Guiyang, 550025, China.
| | - Xin Mu
- School of Mechatronics Engineering, Guizhou Minzu University, Guiyang, 550025, China
| | - Xiaosong Luo
- School of Mechatronics Engineering, Guizhou Minzu University, Guiyang, 550025, China
| | - Hanxian Meng
- School of Mechatronics Engineering, Guizhou Minzu University, Guiyang, 550025, China
| | - Hong Wang
- School of Mechatronics Engineering, Guizhou Minzu University, Guiyang, 550025, China
| | - Li Jin
- School of Mechatronics Engineering, Guizhou Minzu University, Guiyang, 550025, China
| | - Xinsheng Li
- School of Resources, Environment and Materials, Guangxi University, Nanning, 530004, China.
| | - Baosheng Lai
- Ningbo Shuanglin Mould Auto Parts Co. Ltd., Ningbo, 315613, China.
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30
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Charitopoulou MA, Kalogiannis KG, Lappas AA, Achilias DS. Novel trends in the thermo-chemical recycling of plastics from WEEE containing brominated flame retardants. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:59190-59213. [PMID: 32638300 DOI: 10.1007/s11356-020-09932-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Accepted: 06/29/2020] [Indexed: 05/28/2023]
Abstract
The amount of plastics from waste electric and electronic equipment (WEEE) has enormously increased nowadays, due to the rapid expansion and consumption of electronic devices and their short lifespan. This, in combination with their non-biodegradability, led to the need to explore environmentally friendly solutions for their safe disposal. One main obstacle when recycling plastics from WEEE is that they usually comprise harmful additives such as brominated flame retardants (BFRs) that need to be removed before or during their recycling. This paper reviews existing techniques for the recycling of plastics from WEEE and focuses specifically on the advantages, disadvantages, and challenges of pyrolysis as an environmentally friendly method for the production of value-added materials (monomers, hydrocarbons, phenols, etc.). Current technological trends available for the recycling of plastics containing brominated flame retardants are reviewed in an attempt to provide insights for future research on the sustainable management of plastics from WEEE. Emphasis is given on conventional pyrolysis, where a pretreatment step for the debromination of products is applied. This is required since brominated compounds treated at high temperatures may result in the production of harmful to health compounds such as dioxins. All current pretreatment methods (solvent extraction, supercritical fluid technology, etc.) are presented and compared in detail. Co-pyrolysis is also investigated, as it seems to be a very interesting approach, since no catalysts or solvents are used, and at the same time, more plastic wastes can be consumed as feedstock. Furthermore, catalytic pyrolysis along with key parameters, such as the type of the catalyst or pyrolysis temperature, are fully analyzed. Catalysts affect the products' distribution and enhance the removal of bromine from pyrolysis oils. Finally, an emerging technique, that of microwave-assisted pyrolysis, is also highlighted, as it offers many advantages over conventional pyrolysis. Of course, there are some impediments, such as the operational costs or other difficulties as regards the industrial implementation of the mentioned techniques that need to be overcome through future works.
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Affiliation(s)
- Maria Anna Charitopoulou
- Laboratory of Polymers and Dyes Chemistry and Technology, Department of Chemistry, Aristotle University of Thessaloniki, 541 24, Thessaloniki, Greece
| | - Konstantinos G Kalogiannis
- Chemical Process and Energy Resources Institute, Centre for Research and Technology Hellas, 57001 Thermi, Thessaloniki, Greece
| | - Angelos A Lappas
- Chemical Process and Energy Resources Institute, Centre for Research and Technology Hellas, 57001 Thermi, Thessaloniki, Greece
| | - Dimitriοs S Achilias
- Laboratory of Polymers and Dyes Chemistry and Technology, Department of Chemistry, Aristotle University of Thessaloniki, 541 24, Thessaloniki, Greece.
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31
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Wu Y, Liu G, Pan D, Yuan H, Li B. A new mechanism and kinetic analysis for the efficient conversion of inorganic bromide in waste printed circuit board smelting ash via traditional sulfated roasting. JOURNAL OF HAZARDOUS MATERIALS 2021; 413:125394. [PMID: 33607586 DOI: 10.1016/j.jhazmat.2021.125394] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 12/21/2020] [Accepted: 02/09/2021] [Indexed: 06/12/2023]
Abstract
The waste printed circuit board smelting ash (WPCB-SA) produced in the waste printed circuit board smelting process is a hazardous material that not only contains valuable metals, but also contains a large amount of toxic and harmful inorganic bromides. The utilization of metals has received considerable attention in previous studies, but the recovery of hazardous bromides requires further study. In this article, a new idea of converting inorganic bromine in WPCB-SA by traditional sulfated roasting is proposed. Debromination kinetics under simulated experimental conditions are discussed, and kinetic equations are established. The kinetic results show that during low-temperature sulfated roasting, the conversion of Br in CuBr and PbBr2 conforms to the chemical reaction diffusion model and diffusion control the product layer model, respectively. A possible reaction mechanism is also proposed. Our research shows that the conversion of Br in CuBr is divided into three processes: covalent bond decomposition, hydrogen ion form acid, copper ion form salt, and HBr oxidation conversion, whereas the conversion of Br in PbBr2 is divided into two processes: sulfuric acid ionization, lead ion form salt and HBr oxidation conversion. This work provides the theoretical basis for the improvement and application of inorganic bromide recovery technology in WPCB-SA.
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Affiliation(s)
- Yufeng Wu
- Faculty of Materials and Manufacturing, Beijing University of Technology, Beijing 100124, PR China; Institute of Circular Economy, Beijing University of Technology, Beijing 100124, PR China.
| | - Gongqi Liu
- Faculty of Materials and Manufacturing, Beijing University of Technology, Beijing 100124, PR China; Institute of Circular Economy, Beijing University of Technology, Beijing 100124, PR China
| | - De'an Pan
- Faculty of Materials and Manufacturing, Beijing University of Technology, Beijing 100124, PR China; Institute of Circular Economy, Beijing University of Technology, Beijing 100124, PR China
| | - Haoran Yuan
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, PR China
| | - Bin Li
- Faculty of Materials and Manufacturing, Beijing University of Technology, Beijing 100124, PR China; Institute of Circular Economy, Beijing University of Technology, Beijing 100124, PR China
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32
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Thanh Truc NT, Le HA, Lee BK. Sono-oxidation treatment of hazardous ABS/PC surface for its selective separation from ESR styrene plastics. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:24771-24784. [PMID: 33244696 DOI: 10.1007/s11356-020-11796-8] [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: 04/16/2020] [Accepted: 11/23/2020] [Indexed: 06/11/2023]
Abstract
This study reports the selective hydrophilization of the ABS/PC blend surface using the peroxide-sonochemical system and then its selective separation by froth flotation technique from other ABS-based plastics (ABS, ABS/PMMA) and PS/HIPS in electronic shredder residue (ESR). FT-IR and XPS measurements confirm that the hydrophilic moiety development on the ABS/PC surface led to increasing the wettability of ABS/PC and then decreased its floatability. The confocal scanning results also support the enhancement of microscale roughness of the treated ABS/PC surface. The enhanced surface roughness is attributed to the oxidative process which degrades hydrophobic moieties and promotes hydrophilic functional groups on the ABS/PC surface using commercial oxidant peroxide and ultrasound. This study also investigated removal of Br-containing compounds on the ABS/PC surface. The optimum conditions for selectively ABS/PC separation are peroxide concentration 2%, power cycle 70%, treatment time 5 min, temperature 50 °C, floating agent concentration 0.4 mg/L, flotation time 2 min, and airflow rate 0.5 L/min. ABS/PC was selectively separated from ESR styrene plastics with high recovery and purity of 98.9% and 99.8%, respectively. Hence, the developed novel surface treatments having removal of hazardous Br chemicals and none-formation of secondary pollutants should be applied for upgrading plastic recycling quality.
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Affiliation(s)
- Nguyen Thi Thanh Truc
- Institute for the Environmental Science, Engineering and Management, Industrial University of Ho Chi Minh City, No.12, Nguyen Van Bao Street, Ward 4, Go Vap District, Ho Chi Minh City, 70000, Vietnam
| | - Hung Anh Le
- Institute for the Environmental Science, Engineering and Management, Industrial University of Ho Chi Minh City, No.12, Nguyen Van Bao Street, Ward 4, Go Vap District, Ho Chi Minh City, 70000, Vietnam
| | - Byeong-Kyu Lee
- Department of Civil and Environmental Engineering, University of Ulsan, Daehakro 93, Namgu, Ulsan, 44610, Republic of Korea.
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33
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Chemical Recycling of WEEE Plastics—Production of High Purity Monocyclic Aromatic Chemicals. Processes (Basel) 2021. [DOI: 10.3390/pr9030530] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
More than 200 kg real waste electrical and electronic equipment (WEEE) shredder residues from a German dismantling plant were treated at 650 °C in a demonstration scale thermochemical conversion plant. The focus within this work was the generation, purification, and analysis of pyrolysis oil. Subsequent filtration and fractional distillation were combined to yield basic chemicals in high purity. By means of fractional distillation, pure monocyclic aromatic fractions containing benzene, toluene, ethylbenzene, and xylene (BTEX aromatics) as well as styrene and α-methyl styrene were isolated for chemical recycling. Mass balances were determined, and gas chromatography–mass spectrometry (GC-MS) as well as energy dispersive X-ray fluorescence (EDXRF) measurements provided data on the purity and halogen content of each fraction. This work shows that thermochemical conversion and the subsequent refining by fractional distillation is capable of recycling WEEE shredder residues, producing pure BTEX and other monocyclic aromatic fractions. A significant decrease of halogen content (up to 99%) was achieved with the applied methods.
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Schwarz AE, Ligthart TN, Godoi Bizarro D, De Wild P, Vreugdenhil B, van Harmelen T. Plastic recycling in a circular economy; determining environmental performance through an LCA matrix model approach. WASTE MANAGEMENT (NEW YORK, N.Y.) 2021; 121:331-342. [PMID: 33412464 DOI: 10.1016/j.wasman.2020.12.020] [Citation(s) in RCA: 54] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 12/09/2020] [Accepted: 12/12/2020] [Indexed: 05/24/2023]
Abstract
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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Affiliation(s)
- A E Schwarz
- Netherlands Organization for Applied Scientific Research (TNO), Princetonlaan 8, 3584 CB Utrecht, the Netherlands.
| | - T N Ligthart
- Netherlands Organization for Applied Scientific Research (TNO), Princetonlaan 8, 3584 CB Utrecht, the Netherlands
| | - D Godoi Bizarro
- Netherlands Organization for Applied Scientific Research (TNO), Princetonlaan 8, 3584 CB Utrecht, the Netherlands
| | - P De Wild
- Netherlands Organization for Applied Scientific Research (TNO), Westerduinweg 3, 1755 LE Petten, the Netherlands
| | - B Vreugdenhil
- Netherlands Organization for Applied Scientific Research (TNO), Westerduinweg 3, 1755 LE Petten, the Netherlands
| | - T van Harmelen
- Netherlands Organization for Applied Scientific Research (TNO), Princetonlaan 8, 3584 CB Utrecht, the Netherlands
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35
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Gao R, Liu B, Zhan L, Guo J, Zhang J, Xu Z. Catalytic effect and mechanism of coexisting copper on conversion of organics during pyrolysis of waste printed circuit boards. JOURNAL OF HAZARDOUS MATERIALS 2021; 403:123465. [PMID: 32846256 DOI: 10.1016/j.jhazmat.2020.123465] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 06/30/2020] [Accepted: 07/14/2020] [Indexed: 06/11/2023]
Abstract
Pyrolysis is a promising technology for recycling organic materials from waste printed circuit boards (WPCBs). Nevertheless, the generated organic bromides are toxic and urgently needed to be removed. The coexisting copper (Cu) of WPCBs has potential performance on debromination. However, the catalytic effect and mechanism of Cu on pyrolysis process and products were still unclear. To clarify the in-situ catalysis of Cu, the analysis on kinetics and pyrolysis products was performed. The results showed that Cu can change the mechanism function of pyrolysis, which reduced the apparent activation energy (Ea). The mechanism function of Cu-coated WPCBs was obtained by Šesták-Berggren model and expressed as: dαdt=1.65×107×1-α-1.30α6.09-ln1-α-6.03exp-202.45KJ/molRT. Product analysis suggested that Cu promoted the conversion of organic bromides to Br2 and HBr. During the process of pyrolysis, bromide atoms interacted with Cu to form coordination compound, which can weaken the strength of C-Br bond and generate bromide free radical (Br*). Besides, Cu can promote the conversion of aromatic-Br to Br2 as the catalyst for Ullmann cross-coupling reaction. Therefore, the presence of Cu was beneficial to pyrolysis. This work provided the theoretical basis for the improvement and application of pyrolysis technology.
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Affiliation(s)
- Ruitong Gao
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, PR China
| | - Binyang Liu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, PR China
| | - Lu Zhan
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, PR China
| | - Jie Guo
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, PR China
| | - Jie Zhang
- Instrumental Analysis Center, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, PR China
| | - Zhenming Xu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, PR China.
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36
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Zhang T, Mao X, Qu J, Liu Y, Siyal AA, Ao W, Fu J, Dai J, Jiang Z, Deng Z, Song Y, Wang D, Polina C. Microwave-assisted catalytic pyrolysis of waste printed circuit boards, and migration and distribution of bromine. JOURNAL OF HAZARDOUS MATERIALS 2021; 402:123749. [PMID: 33254771 DOI: 10.1016/j.jhazmat.2020.123749] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 08/18/2020] [Accepted: 08/19/2020] [Indexed: 06/12/2023]
Abstract
Microwave-assisted pyrolysis (MAP) of waste printed circuit boards (WPCB) was performed to investigate the characteristics of pyrolysis product and Br fixation. Pyrolysis conversion increased with increasing temperature, reaching 93.3 % at 650 °C. However, increasing heating time did not exhibit remarkable influence on pyrolysis conversion. At 350 °C, phenols were main compounds in the oil accounting for 91.15 %. As the temperature increased to 650 °C, polycyclic aromatic hydrocarbons and monocyclic aromatic hydrocarbons (except phenols) increased to 20.55 % and 19.03 %, respectively. Meanwhile, the total content of CO2, CO, CH4 and H2 in the non-condensable gases increased significantly. Addition of ZSM-5 and kaolin promoted the recombination reaction of pyrolysis products, increased the relative percentage of monocyclic aromatic hydrocarbons (except phenols) and C11-C20 compounds in the oil, and reduced non-condensable gases. The oxygen bomb-ion chromatography was used to evaluate the Br content of pyrolysis residues. Higher pyrolysis temperature enhanced transfer of Br to pyrolysis gas. K2CO3, Na2CO3 and NaOH reacted with hydrogen bromide to generate KBr and NaBr, which significantly improved the Br fixation efficiency of pyrolysis residues (i.e. from 29.11%-99.80%, 96.39 % and 86.69 %, respectively) and reduced Br content in pyrolysis gas.
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Affiliation(s)
- Tianhao Zhang
- State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, 15 Beisanhua East Road, Chaoyang District, Beijing, 100029, China; College of Chemical Engineering, Beijing University of Chemical Technology, 15 Beisanhua East Road, Chaoyang District, Beijing, 100029, China
| | - Xiao Mao
- State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, 15 Beisanhua East Road, Chaoyang District, Beijing, 100029, China; College of Chemical Engineering, Beijing University of Chemical Technology, 15 Beisanhua East Road, Chaoyang District, Beijing, 100029, China
| | - Juanshen Qu
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, 15 Beisanhua East Road, Chaoyang District, Beijing, 100029, China
| | - Yang Liu
- State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, 15 Beisanhua East Road, Chaoyang District, Beijing, 100029, China; College of Chemical Engineering, Beijing University of Chemical Technology, 15 Beisanhua East Road, Chaoyang District, Beijing, 100029, China; Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, 15 Beisanhua East Road, Chaoyang District, Beijing, 100029, China
| | - Asif Ali Siyal
- State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, 15 Beisanhua East Road, Chaoyang District, Beijing, 100029, China; College of Chemical Engineering, Beijing University of Chemical Technology, 15 Beisanhua East Road, Chaoyang District, Beijing, 100029, China
| | - Wenya Ao
- State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, 15 Beisanhua East Road, Chaoyang District, Beijing, 100029, China; College of Chemical Engineering, Beijing University of Chemical Technology, 15 Beisanhua East Road, Chaoyang District, Beijing, 100029, China; Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, 15 Beisanhua East Road, Chaoyang District, Beijing, 100029, China
| | - Jie Fu
- State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, 15 Beisanhua East Road, Chaoyang District, Beijing, 100029, China; College of Chemical Engineering, Beijing University of Chemical Technology, 15 Beisanhua East Road, Chaoyang District, Beijing, 100029, China
| | - Jianjun Dai
- State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, 15 Beisanhua East Road, Chaoyang District, Beijing, 100029, China; College of Chemical Engineering, Beijing University of Chemical Technology, 15 Beisanhua East Road, Chaoyang District, Beijing, 100029, China.
| | - Zhihui Jiang
- State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, 15 Beisanhua East Road, Chaoyang District, Beijing, 100029, China; College of Chemical Engineering, Beijing University of Chemical Technology, 15 Beisanhua East Road, Chaoyang District, Beijing, 100029, China
| | - Zeyu Deng
- State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, 15 Beisanhua East Road, Chaoyang District, Beijing, 100029, China; College of Chemical Engineering, Beijing University of Chemical Technology, 15 Beisanhua East Road, Chaoyang District, Beijing, 100029, China
| | - Yongmeng Song
- State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, 15 Beisanhua East Road, Chaoyang District, Beijing, 100029, China; College of Chemical Engineering, Beijing University of Chemical Technology, 15 Beisanhua East Road, Chaoyang District, Beijing, 100029, China
| | - Daiying Wang
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, 15 Beisanhua East Road, Chaoyang District, Beijing, 100029, China
| | - Chtaeva Polina
- State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, 15 Beisanhua East Road, Chaoyang District, Beijing, 100029, China; College of Chemical Engineering, Beijing University of Chemical Technology, 15 Beisanhua East Road, Chaoyang District, Beijing, 100029, China
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37
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Kan Y, Zheng F, Zhang R. Comparative study of pyrolytic carbons prepared from printed circuit boards by magnetic and electrostatic separation. RSC Adv 2021; 11:33490-33499. [PMID: 35497561 PMCID: PMC9042252 DOI: 10.1039/d1ra05287j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Accepted: 10/08/2021] [Indexed: 11/21/2022] Open
Abstract
To discover the influence of separation technologies for PCBs on the preparation, characterization and application of pyrolytic carbon, two kinds of nonmetal fraction from magnetic and electrostatic separation were chosen as the precursors.
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Affiliation(s)
- Yujiao Kan
- College of Safety and Environmental Engineering, Shandong University of Science and Technology, Qingdao 266590, China
| | - Fangyuan Zheng
- College of Safety and Environmental Engineering, Shandong University of Science and Technology, Qingdao 266590, China
| | - Ruxin Zhang
- College of Safety and Environmental Engineering, Shandong University of Science and Technology, Qingdao 266590, China
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38
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Hussain Z, Imtiaz M, Naz MY, Khan KM, AbdEl‐Salam NM, Ibrahim KA. Thermal and clinker‐catalyzed pyrolyses of polystyrene waste using the Portland cement solid‐base catalyst. ASIA-PAC J CHEM ENG 2021. [DOI: 10.1002/apj.2556] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Zahid Hussain
- Department of Chemistry Abdul Wali Khan University Mardan Pakistan
| | - Maria Imtiaz
- Department of Chemistry Abdul Wali Khan University Mardan Pakistan
| | - Muhammad Y. Naz
- Department of Physics University of Agriculture Faisalabad Pakistan
| | - Khalid M. Khan
- International Centre for Chemical and Biological Sciences University of Karachi Karachi Pakistan
| | | | - Khalid A. Ibrahim
- College of Engineering, Muzahimiyah Branch King Saud University Riyadh Saudi Arabia
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39
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Mark LO, Cendejas MC, Hermans I. The Use of Heterogeneous Catalysis in the Chemical Valorization of Plastic Waste. CHEMSUSCHEM 2020; 13:5808-5836. [PMID: 32997889 DOI: 10.1002/cssc.202001905] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2020] [Revised: 09/22/2020] [Indexed: 05/25/2023]
Abstract
Plastic solid waste (PSW) is an ever-growing environmental challenge for our society, as it not only ends up in landfills but also in waterways and oceans and is consequently entering the food chain. A key strategy to overcome this problem while also preserving carbon resources is to use PSW as a feedstock, evolving towards a circular economy. To implement this, mechanical as well as chemical recycling technologies must be developed. Indeed, owing to the high volume of PSW generated each year, mechanical recycling alone is not adequate for addressing this global challenge. Because of this, chemical recycling via thermal and heterogeneous catalytic conversion has received growing attention. This process has the potential to take PSW and convert it into usable monomers, fuels, synthesis gas, and adsorbents under more sustainable conditions than thermal degradation. This Review highlights the recent research advances in catalytic technologies for PSW conversion and valorization.
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Affiliation(s)
- Lesli O Mark
- Department of Chemistry, University of Wisconsin - Madison, 1101 University Avenue, Madison, WI, 53706, USA
| | - Melissa C Cendejas
- Department of Chemistry, University of Wisconsin - Madison, 1101 University Avenue, Madison, WI, 53706, USA
| | - Ive Hermans
- Department of Chemistry, University of Wisconsin - Madison, 1101 University Avenue, Madison, WI, 53706, USA
- Department of Chemical and Biological Engineering, University of Wisconsin - Madison, 1415 Engineering Drive, Madison, WI, 53706, USA
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40
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Energy Recovery via Thermal Gasification from Waste Insulation Electrical Cables (WIEC). APPLIED SCIENCES-BASEL 2020. [DOI: 10.3390/app10228253] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The recovery of noble metals from electrical wires and cables results in waste materials such as polyvinyl chloride (PVC) and polyethylene (PE), that is, waste insulation electrical cables (WIEC), which have been processed by gasification for energy recovery. This study focused on the effect of blending the ratio of WIEC on the gasification feedstock composition and the lower heating value (LHV) of produced syngas, through controlled tests and tests under different loads on the generator. The controlled gasification experiments were carried out at blending ratios between pine biomass and WIEC of 90:10, 80:20, and 70:30 and with pine biomass only (100%). For the loads gasification, the experiments were carried out at a blending ratio of 80:20. The controlled experimental results presented that the highest hydrogen content, approximated 17.7 vol.%, was observed at a blending ratio of 70:30 between pine biomass and WIEC and the highest LHV of syngas was observed at a blending ratio of 90:10, with 5.7 MJ/Nm3. For the load gasification experiments, the results showed that the highest hydrogen content was obtained with a load of 15 kW in the generator, approximately 18.48 vol.% of hydrogen content, and the highest LHV of synthesis gas was observed during the 5 kW test, with 5.22 MJ/Nm3. Overall, the new processing of waste insulation electrical cables using a downdraft gasification reactor demonstrates great promise for high quality syngas production.
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41
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Miao F, Liu Y, Gao M, Yu X, Xiao P, Wang M, Wang S, Wang X. Degradation of polyvinyl chloride microplastics via an electro-Fenton-like system with a TiO 2/graphite cathode. JOURNAL OF HAZARDOUS MATERIALS 2020; 399:123023. [PMID: 32535518 DOI: 10.1016/j.jhazmat.2020.123023] [Citation(s) in RCA: 103] [Impact Index Per Article: 25.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Revised: 05/20/2020] [Accepted: 05/21/2020] [Indexed: 05/26/2023]
Abstract
Nowadays, microplastic pollution has been brought into focus for its hazards to aquatic life. However, researches on the electrocatalytic treatment for efficient degradation of microplastics are still insufficient. Herein, an electro-Fenton like (EF-like) technology based on TiO2/graphite (TiO2/C) cathode was put forward to degrade polyvinyl chloride (PVC), a typical microplastic in water. It exhibited a remarkable performance on PVC degradation via cathodic reduction dechlorination and hydroxyl radical (OH) oxidation simultaneously. Besides, the effects of reaction temperature and initial PVC concentration were investigated. Under optimal conditions, the dechlorination efficiency of PVC reached 75 % after potentiostatic electrolysis at -0.7 V vs. Ag/AgCl for 6 h. The intermediate products were explored during the degradation of PVC microplastics. The surface morphologies and molecular weight of PVC changed accordingly. Based on these results, a possible degradation process for PVC was proposed. This work demonstrated that such a heterogeneous EF-like technology using TiO2/C cathode was hopefully to provide an eco-friendly method for microplastic wastewater treatment.
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Affiliation(s)
- Fei Miao
- Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao, 266200, China
| | - Yanfeng Liu
- Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao, 266200, China
| | - Mingming Gao
- Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao, 266200, China.
| | - Xin Yu
- Institute for Advanced Interdisciplinary Research (iAIR), University of Jinan, Jinan, 250022, China
| | - Pengwei Xiao
- Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao, 266200, China
| | - Mei Wang
- The Key Laboratory of Plant Development and Environment Adaptation Biology, Ministry of Education, School of Life Science, Shandong University, Qingdao, 266237, China
| | - Shuguang Wang
- Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao, 266200, China
| | - Xinhua Wang
- Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao, 266200, China
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42
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Khan MJ, Singh R, Shewani K, Shukla P, Bhaskar PV, Joshi KB, Vinayak V. Exopolysaccharides directed embellishment of diatoms triggered on plastics and other marine litter. Sci Rep 2020; 10:18448. [PMID: 33116244 PMCID: PMC7595185 DOI: 10.1038/s41598-020-74801-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Accepted: 10/06/2020] [Indexed: 12/22/2022] Open
Abstract
In the present study, embellishment or beautification of diatoms on substrates like plastics, polydimethylsiloxane, graphite, glass plate, and titanium dioxide, triggered by exopolysaccharides was examined under laboratory conditions. Exopolysaccharides are secreted mainly by primary colonisers, bacteria, which is succeeded by secondary colonisers i.e. diatoms. Both diatom (Nitzschia sp.4) and bacteria (Bacillus subtilis) were exposed with substrates separately for 30 days. Diatoms adhere on substrates strongly, not only because of surface roughness of different substrates but also the nanoporous architecture of diatoms which enhanced their embellishment. This study attempted to identify the substrates that adhere to diatoms strongly and was mainly analyzed by scanning electron microscope and further the observations are well supported by math work software (MATLAB). The variation of diatom's binding on different substrates is due to the influence of marine litters on diatom population in ocean beds where they undergo slow degradation releasing macro, micro and nanoparticles besides radicals and ions causing cell death. Therefore a proof-of-concept model is developed to successfully deliver a message concerning benefit of using different diatom species.
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Affiliation(s)
- Mohd Jahir Khan
- Diatom Nanoengineering and Metabolism Laboratory (DNM), School of Applied Sciences, Dr. Harisingh Gour Central University, Sagar, Madhya Pradesh, 470003, India
| | - Ramesh Singh
- Department of Chemistry, School of Chemical Science and Technology, Dr. Harisingh Gour Central University, Sagar, Madhya Pradesh, 470003, India
| | - Kunal Shewani
- Department of Physics, School of Physical and Mathematical Sciences, Dr. Harisingh Gour Central University, Sagar, Madhya Pradesh, 470003, India
| | - Prashant Shukla
- Department of Physics, School of Physical and Mathematical Sciences, Dr. Harisingh Gour Central University, Sagar, Madhya Pradesh, 470003, India
| | - P V Bhaskar
- National Centre for Polar and Oceanic Research, Vasco Da Gama, Goa, 403804, India
| | - Khashti Ballabh Joshi
- Department of Chemistry, School of Chemical Science and Technology, Dr. Harisingh Gour Central University, Sagar, Madhya Pradesh, 470003, India
| | - Vandana Vinayak
- Diatom Nanoengineering and Metabolism Laboratory (DNM), School of Applied Sciences, Dr. Harisingh Gour Central University, Sagar, Madhya Pradesh, 470003, India.
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43
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Process integration of E-waste carbonization and High-gravity rotating packed bed for optimal gold recovery and the fine particles reduction. Sep Purif Technol 2020. [DOI: 10.1016/j.seppur.2020.116686] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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Chen T, Yu J, Ma C, Bikane K, Sun L. Catalytic performance and debromination of Fe-Ni bimetallic MCM-41 catalyst for the two-stage pyrolysis of waste computer casing plastic. CHEMOSPHERE 2020; 248:125964. [PMID: 32004884 DOI: 10.1016/j.chemosphere.2020.125964] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Revised: 01/13/2020] [Accepted: 01/18/2020] [Indexed: 05/25/2023]
Abstract
A computer casing plastic waste containing brominated flame retardants (BFRs) was pyrolyzed in a two-stage vertical quartz tube reactor using iron and nickel metals modified MCM-41 catalysts. Various catalysts with different ratios of Fe and Ni were prepared and utilized to study their catalytic performance. At the presence of 20%Ni/MCM-41 catalyst, the pyrolytic yield of oil and gas reached maximum values of 49.9 wt% and 13.8 wt% respectively. The co-existence of Fe and Ni showed synergistic effect on oil composition by promoting the formation of valuable single ring hydrocarbons. With regard to the 15%Fe-5%Ni/MCM-41, 10%Fe-10%Ni/MCM-41 and 5%Fe-15%Ni/MCM-41 catalysts, the production of single ring hydrocarbons were 64.58%, 65.93% and 64.74% respectively. The bimetallic catalysts also exhibited remarkable effect on eliminating bromine from pyrolytic oil. At the presence of Fe-Ni/MCM-41, the bromine in pyrolytic oil was reduced to below 4 wt% compared with 10 wt% without catalyst. Higher amounts of Fe in the catalyst is beneficial for the debromination efficiency. The debromination process by the Fe-Ni/MCM-41 may be realized by these different mechanisms: catalytic cracking of organobromines, reaction of loaded metal oxides with HBr/SbBr3, and deposition of organobromines on the surface of catalyst.
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Affiliation(s)
- Tao Chen
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, 430074, Wuhan, China
| | - Jie Yu
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, 430074, Wuhan, China.
| | - Chuan Ma
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, 430074, Wuhan, China
| | - Kagiso Bikane
- Department of Chemical Engineering, Imperial College London, South Kensington Campus, London, SW7 2AZ, UK
| | - Lushi Sun
- State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, 430074, Wuhan, China.
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Jandric A, Part F, Fink N, Cocco V, Mouillard F, Huber-Humer M, Salhofer S, Zafiu C. Investigation of the heterogeneity of bromine in plastic components as an indicator for brominated flame retardants in waste electrical and electronic equipment with regard to recyclability. JOURNAL OF HAZARDOUS MATERIALS 2020; 390:121899. [PMID: 31879115 DOI: 10.1016/j.jhazmat.2019.121899] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Revised: 11/22/2019] [Accepted: 12/13/2019] [Indexed: 06/10/2023]
Abstract
Waste electrical and electronic equipment (WEEE) can contain brominated flame retardants (BFRs) that pose a threat to human health and the environment. In addition, Br-containing plastics reduce the recycling potential of WEEE. In order to gain a better insight into the distribution of Br in plastics from WEEE, the total concentration of Br was measured on the level of device types and plastic components using handheld X-ray fluorescence (hXRF). In 35 % of the sample size (882 components from 369 different devices, which originate from 6 device types) Br was detected, 5 % exceeded the RoHS limit. Only few and older devices contained high Br concentrations, while the majority were below the RoHS limit and could be recycled. In addition, 18 different plastic types were identified by infrared spectroscopy, with acrylonitrile butadiene styrene being the most abundant (44 % of all samples). Manual dismantling of devices into individual plastic components enabled us to examine Br hotspots and the variety of plastic types in WEEE. Based on this analytical procedure, WEEE recyclers could exclude certain equipment or plastic components (e.g. power supplies or PC housings) directly on-site prior to WEEE recycling and shredding in order to produce high-quality recycled products and avoid cross-contamination.
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Affiliation(s)
- A Jandric
- Department of Water-Atmosphere-Environment, Institute of Waste Management, University of Natural Resources and Life Sciences, Muthgasse 107, 1190 Vienna, Austria
| | - F Part
- Department of Water-Atmosphere-Environment, Institute of Waste Management, University of Natural Resources and Life Sciences, Muthgasse 107, 1190 Vienna, Austria; Department of Nanobiotechnology, Institute for Synthetic Bioarchitectures, University of Natural Resources and Life Sciences, Muthgasse 11/II, 1190 Vienna, Austria.
| | - N Fink
- Department of Water-Atmosphere-Environment, Institute of Waste Management, University of Natural Resources and Life Sciences, Muthgasse 107, 1190 Vienna, Austria
| | - V Cocco
- Department of Civil and Environmental Engineering and Architecture, University of Cagliari, Via Marengo 2, 09123 Cagliari, Italy
| | - F Mouillard
- Department of Water-Atmosphere-Environment, Institute of Waste Management, University of Natural Resources and Life Sciences, Muthgasse 107, 1190 Vienna, Austria
| | - M Huber-Humer
- Department of Water-Atmosphere-Environment, Institute of Waste Management, University of Natural Resources and Life Sciences, Muthgasse 107, 1190 Vienna, Austria
| | - S Salhofer
- Department of Water-Atmosphere-Environment, Institute of Waste Management, University of Natural Resources and Life Sciences, Muthgasse 107, 1190 Vienna, Austria
| | - C Zafiu
- Department of Water-Atmosphere-Environment, Institute of Waste Management, University of Natural Resources and Life Sciences, Muthgasse 107, 1190 Vienna, Austria
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Chen B, He J, Sun X, Zhao J, Jiang H, Zhang L. Separating and recycling metal mixture of pyrolyzed waste printed circuit boards by a combined method. WASTE MANAGEMENT (NEW YORK, N.Y.) 2020; 107:113-120. [PMID: 32278216 DOI: 10.1016/j.wasman.2020.04.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2020] [Revised: 04/02/2020] [Accepted: 04/04/2020] [Indexed: 06/11/2023]
Abstract
Waste printed circuit boards (WPCBs) contain a variety of valuable and hazardous materials. Recycling WPCBs is an important subject not only for environmental protection but also for sustainable development of resources. In this work, a new method combined low-temperature alkaline smelting with liquid-liquid phase separation is proposed to separate and recycle metal mixture in pyrolysis residue of WPCBs of mobile phones. During the low-temperature alkaline smelting process, amphoteric metals Al, Pb, Si, Sn, and Zn are firstly separated and recycled from the metal mixture with the separation rates of 99.5%, 81.6%, 97.8%, 88.4% and 95.7%, respectively. To separate the remaining metal mixture mainly containing elements Cu, Fe, Cr, Ni, Au and Ag, a liquid-liquid phase separation system is designed. As a result, the noble metals Au and Ag are concentrated in the copper-rich substance to form a high-value group, while the elements Ni and Cr distribute in the iron-rich substance. The iron-rich substance can be reused in the liquid-liquid phase separation process. In the super-gravity field, the recycling rates of the metals Au, Ag, Cr and Ni reach 98.1%, 99.8%, 95.6% and 75.4%, respectively. Furthermore, the iron-rich substance can be reused back to the liquid-liquid separation system. The copper-rich substance enriched by the noble metals can be efficiently recovered with low energy consumption and less pollution. This work provides an environmentally friendly and efficient route for separating and recycling the metal mixture in WPCBs.
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Affiliation(s)
- Bin Chen
- Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China; School of Materials Science and Engineering, University of Science and Technology of China, Shenyang 110016, China
| | - Jie He
- Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China; School of Materials Science and Engineering, University of Science and Technology of China, Shenyang 110016, China.
| | - Xiaojun Sun
- Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China; School of Materials Science and Engineering, University of Science and Technology of China, Shenyang 110016, China
| | - Jiuzhou Zhao
- Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China; School of Materials Science and Engineering, University of Science and Technology of China, Shenyang 110016, China
| | - Hongxiang Jiang
- Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China
| | - Lili Zhang
- Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China
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Zhan L, Zhao X, Ahmad Z, Xu Z. Leaching behavior of Sb and Br from E-waste flame retardant plastics. CHEMOSPHERE 2020; 245:125684. [PMID: 31875573 DOI: 10.1016/j.chemosphere.2019.125684] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Revised: 11/29/2019] [Accepted: 12/16/2019] [Indexed: 06/10/2023]
Abstract
The improper disposal of E-waste flame retardant plastics laden with antimony (Sb) and bromine (Br) has brought enormous environmental hazards, however, rare information on the effective removal of Sb and Br is available. In this study, through building an alkaline sulfide system under hydrothermal conditions, Sb and Br were simultaneously extracted from flame retardant plastic with high efficiency of 85.60% and 90.13%, respectively. Sulfur ion through mass transfer reacted with encapsulated Sb2O3 to form safe and non-toxic SbS33-. Alkaline solution trapped the Br through substitution or neutralization reaction to inhibit the formation of brominated organic compounds. The results showed that the optimum temperature, residence time, Na2S and NaOH concentration for hydrothermal removal of Sb and Br were 220 °C, 2 h, 50 g/L and 20 g/L. The results also revealed that both Na2S and NaOH played an interrelated role in the process of Sb removal. However, NaOH was the only factor controlling the process of debromination. Moreover, the FTIR structure of plastic after alkaline sulfide hydrothermal treatment remained unchanged, which implies that the treated plastic can be reused, and is an added advantage of this technology. The TG-DTG analysis proved the effectiveness of alkaline sulfide hydrothermal treatment in removing Sb and Br.
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Affiliation(s)
- Lu Zhan
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China; Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Science, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China; Shanghai Institute of Pollution Control and Ecological Security, 1515 North Zhongshan Road, Shanghai, 200092, China.
| | - Xuyuan Zhao
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Science, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China
| | - Zahoor Ahmad
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Science, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, China; Department of Soil Science, University of Haripur, Haripur, Khyber Pakhtunkhwa, Pakistan
| | - Zhenming Xu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China; Shanghai Institute of Pollution Control and Ecological Security, 1515 North Zhongshan Road, Shanghai, 200092, China
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48
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Gao R, Zhan L, Guo J, Xu Z. Research of the thermal decomposition mechanism and pyrolysis pathways from macromonomer to small molecule of waste printed circuit board. JOURNAL OF HAZARDOUS MATERIALS 2020; 383:121234. [PMID: 31563045 DOI: 10.1016/j.jhazmat.2019.121234] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Revised: 09/05/2019] [Accepted: 09/13/2019] [Indexed: 06/10/2023]
Abstract
Pyrolysis is an important pre-treatment technology for pyrometallurgy, which could reduce pollution and recover materials from waste printed circuit boards (WPCBs). However, present studies on mechanism of pyrolysis were insufficient, which results in the unclear of controlling reaction rate and inhibiting side reaction. To further develop pyrolysis technology, the in-depth research on the pyrolysis mechanism is necessary. In this study, we investigated the thermal decomposition process and pyrolysis pathways from macromonomers to products of WPCBs. The results showed that HBr was produced at the initial stage of pyrolysis. Then, the resin body depolymerized into macromonomers, followed by random rupture and free radical reactions to form pyrolysis products. Besides, possible mechanism for bisphenol A thermal decomposing was analyzed by bond energy. The results suggested that methyl groups in bisphenol A would be preferentially removed because of low bond energy. The six possible pathways may occur simultaneously when energy sufficient. Moreover, the mechanism function was determined by Škvára-Šesták method as: G(α)=-ln 1-α2, which indicated pyrolysis reaction agreed with the model of random nucleation followed by random growth. This study provided the theoretical basis for pollution control, process optimization and reactor design of WPCBs pyrolysis.
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Affiliation(s)
- Ruitong Gao
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, PR China
| | - Lu Zhan
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China
| | - Jie Guo
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, PR China
| | - Zhenming Xu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China.
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Chen TL, Huang TH, Hsu CH, Chen YH, Pan SY, Chiang PC. Removal of fine particles from IC chip carbonization process in a rotating packed bed: Modeling and assessment. CHEMOSPHERE 2020; 238:124600. [PMID: 31446277 DOI: 10.1016/j.chemosphere.2019.124600] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2019] [Revised: 08/11/2019] [Accepted: 08/15/2019] [Indexed: 06/10/2023]
Abstract
A high-gravity rotating packed bed (HiGee RPB) is very efficient at removing pollution because it exerts a strong high centrifugal and allows tiny droplets to form, which allows the control of gaseous and particulate air pollution. In this study, fine particles that are removed from integrated circuit (IC) chip carbonization process using a RPB are evaluated under different high gravity factors and liquid-to-gas ratios. The greatest number of particles captured per energy consumption is 17.77 mg kWh-1 in a RPB. This allow greater energy efficiency for the HiGee technology prevents an air-energy nexus. The maximum available particle removal efficiency for a RPB is determined using a response surface model (RSM). 99.5% of particles are removed at a high gravity factor of 262 and a liquid-to-gas ratio of 0.24. A semi-theoretical model is developed to determine the particle removal efficiency individually in packing and cavity zones of the RPB. More particles are removed in a cavity zone than in the packing zone as the high gravity factor increases. An empirical model shows that the particle removal efficiency depends on the operating factors. Finally, a comparison analysis of particulate matter treatment in various types of RPB is used to validate the performance in terms of particle removal using high-gravity technology for different industries.
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Affiliation(s)
- Tse-Lun Chen
- Graduate Institute of Environmental Engineering, National Taiwan University, No. 71, Chou-Shan Road, Taipei City, 10673, Taiwan
| | - Tzu-Hao Huang
- Graduate Institute of Environmental Engineering, National Taiwan University, No. 71, Chou-Shan Road, Taipei City, 10673, Taiwan
| | - Ching-Hsiang Hsu
- UWin Nanotech Company Limited. No. 3, Ln. 12, Yazhou Rd., Tucheng Dist., New Taipei City, 236, Taiwan
| | - Yi-Hung Chen
- Department of Chemical Engineering and Biotechnology, National Taipei University of Technology, No. 1, Section 3, Zhongxiao E. Road, Taipei City, Taiwan, 10608, Taiwan
| | - Shu-Yuan Pan
- Department of Bioenvironmental Systems Engineering, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei City, 10617, Taiwan
| | - Pen-Chi Chiang
- Graduate Institute of Environmental Engineering, National Taiwan University, No. 71, Chou-Shan Road, Taipei City, 10673, Taiwan; Carbon Cycle Research Center, National Taiwan University, No. 71, Fang-Lan Road, Taipei City, 10674, Taiwan.
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50
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Tian S, Luo Y, Ma Y, He H, Jia D, Zhang L, Chen Y. Effects of decoppering pretreatment on accelerated weathering behaviors of waste printed circuit boards powders reinforced polypropylene composites. J Appl Polym Sci 2019. [DOI: 10.1002/app.48224] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Shenghui Tian
- Chongqing Key Laboratory of Nano‐Micro Composite Materials and Devices, School of Metallurgy and Materials EngineeringChongqing University of Science and Technology Chongqing 401331 China
- School of Materials Science and Engineering, Key Lab of Guangdong Province for High Property and Functional Macromolecular MaterialsSouth China University of Technology Guangzhou 510640 People's Republic of China
| | - Yuanfang Luo
- School of Materials Science and Engineering, Key Lab of Guangdong Province for High Property and Functional Macromolecular MaterialsSouth China University of Technology Guangzhou 510640 People's Republic of China
| | - Yuanbin Ma
- School of Materials Science and Engineering, Key Lab of Guangdong Province for High Property and Functional Macromolecular MaterialsSouth China University of Technology Guangzhou 510640 People's Republic of China
| | - Hui He
- School of Materials Science and Engineering, Key Lab of Guangdong Province for High Property and Functional Macromolecular MaterialsSouth China University of Technology Guangzhou 510640 People's Republic of China
| | - Demin Jia
- School of Materials Science and Engineering, Key Lab of Guangdong Province for High Property and Functional Macromolecular MaterialsSouth China University of Technology Guangzhou 510640 People's Republic of China
| | - Ling Zhang
- Chongqing Key Laboratory of Nano‐Micro Composite Materials and Devices, School of Metallurgy and Materials EngineeringChongqing University of Science and Technology Chongqing 401331 China
| | - Yong Chen
- Chongqing Key Laboratory of Nano‐Micro Composite Materials and Devices, School of Metallurgy and Materials EngineeringChongqing University of Science and Technology Chongqing 401331 China
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