1
|
Sannoh F, Fatmi Z, Carpenter DO, Santoso M, Siddique A, Khan K, Zeb J, Hussain MM, Khwaja HA. Air pollution we breathe: Assessing the air quality and human health impact in a megacity of Southeast Asia. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 942:173403. [PMID: 38844217 DOI: 10.1016/j.scitotenv.2024.173403] [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: 02/02/2024] [Revised: 05/01/2024] [Accepted: 05/19/2024] [Indexed: 06/14/2024]
Abstract
With 24 million inhabitants and 6.6 million vehicles on the roads, Karachi, Pakistan ranks among the world's most polluted cities due to high levels of fine particulate matter (PM2.5). This study aims to investigate PM2.5 mass, seasonal and temporal variability, chemical characterization, source apportionment, and health risk assessment at two urban sites in Karachi. Samples were analyzed using ion chromatography and dual-wavelength optical transmissometer for various inorganic components (anions, cations, and trace elements) and black carbon (BC). Several PM2.5 pollution episodes were frequently observed, with annual mean concentrations at Kemari (140 ± 179 μg/m3) and Malir (95 ± 40.9 μg/m3) being significantly above the World Health Organization's guidelines of 5 μg/m3. Chemical composition at both sites exhibited seasonal variability, with higher pollution levels in winter and fall and lower concentrations in summer. The annual average BC concentrations were 4.86 ± 5.29 μg/m3 and 4.52 ± 3.68 μg/m3, respectively. A Positive Matrix Factorization (PMF) analysis identified 5 factors, crustal, sea salt, vehicular exhaust, fossil-fuel combustion, and industrial emission. The health risk assessment indicated a higher number of deaths in colder seasons (fall and winter) at the Kemari (328,794 and 287,814) and Malir (228,406 and 165,737) sites and potential non-carcinogenic and carcinogenic risks to children from metals. The non-carcinogenic risk of PM2.5 bound Pb, Fe, Zn, Mn, Cr, Cu and Ni via inhalation exposure were within the acceptable level (<1) for adults. However, potential non-carcinogenic and carcinogenic health risk posed by Pb and Cr through inhalation were observed for children. The findings exhibit critical levels of air pollution that exceed the safe limits in Karachi, posing significant health risks to children and sensitive groups. Our study underscores the urgent need for effective emission control strategies and policy interventions to mitigate these air pollution risks.
Collapse
Affiliation(s)
- Fatim Sannoh
- Division of Environmental Health Sciences, Wadsworth Center, New York State Department of Health, Empire State Plaza, Albany, NY 12237, United States; Department of Environmental Health Sciences, School of Public Health, University at Albany, Albany, NY, United States
| | - Zafar Fatmi
- Department of Community Health Sciences, The Aga Khan University, Karachi, Pakistan
| | - David O Carpenter
- Institute for the Health and the Environment, University at Albany, Albany, NY, United States
| | | | - Azhar Siddique
- Qatar Environment and Energy Research Institute, Hamad Bin Khalifa University, Doha, Qatar
| | - Kamran Khan
- Chemistry Department, University of Karachi, Karachi, Pakistan
| | - Jahan Zeb
- Department of Environmental and Health Research, The Custodian of the Holy Two Mosques Institute for Hajj and Umra Research, Umm Al-Qura University, Mecca, Saudi Arabia
| | - Mirza M Hussain
- Division of Environmental Health Sciences, Wadsworth Center, New York State Department of Health, Empire State Plaza, Albany, NY 12237, United States; Department of Environmental Health Sciences, School of Public Health, University at Albany, Albany, NY, United States
| | - Haider A Khwaja
- Division of Environmental Health Sciences, Wadsworth Center, New York State Department of Health, Empire State Plaza, Albany, NY 12237, United States; Department of Environmental Health Sciences, School of Public Health, University at Albany, Albany, NY, United States.
| |
Collapse
|
2
|
Xia D, Lee C, Charpentier NM, Deng Y, Yan Q, Gabriel JCP. Drivers and Pathways for the Recovery of Critical Metals from Waste-Printed Circuit Boards. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024:e2309635. [PMID: 38837685 DOI: 10.1002/advs.202309635] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2023] [Revised: 04/15/2024] [Indexed: 06/07/2024]
Abstract
The ever-increasing importance of critical metals (CMs) in modern society underscores their resource security and circularity. Waste-printed circuit boards (WPCBs) are particularly attractive reservoirs of CMs due to their gamut CM embedding and ubiquitous presence. However, the recovery of most CMs is out of reach from current metal-centric recycling industries, resulting in a flood loss of refined CMs. Here, 41 types of such spent CMs are identified. To deliver a higher level of CM sustainability, this work provides an insightful overview of paradigm-shifting pathways for CM recovery from WPCBs that have been developed in recent years. As a crucial starting entropy-decreasing step, various strategies of metal enrichment are compared, and the deployment of artificial intelligence (AI) and hyperspectral sensing is highlighted. Then, tailored metal recycling schemes are presented for the platinum group, rare earth, and refractory metals, with emphasis on greener metallurgical methods contributing to transforming CMs into marketable products. In addition, due to the vital nexus of CMs between the environment and energy sectors, the upcycling of CMs into electro-/photo-chemical catalysts for green fuel synthesis is proposed to extend the recycling chain. Finally, the challenges and outlook on this all-round upgrading of WPCB recycling are outlined.
Collapse
Affiliation(s)
- Dong Xia
- SCARCE Laboratory, Energy Research Institute @ NTU, Nanyang Technological University, Singapore, 639798, Singapore
| | - Carmen Lee
- SCARCE Laboratory, Energy Research Institute @ NTU, Nanyang Technological University, Singapore, 639798, Singapore
- School of Material Science and Engineering, Nanyang Technological University, Singapore, 639798, Singapore
| | - Nicolas M Charpentier
- SCARCE Laboratory, Energy Research Institute @ NTU, Nanyang Technological University, Singapore, 639798, Singapore
- Université Paris-Saclay, CEA, CNRS, NIMBE, LICSEN, Gif-sur-Yvette, 91191, France
| | - Yuemin Deng
- Université Paris-Saclay, CEA, CNRS, NIMBE, LICSEN, Gif-sur-Yvette, 91191, France
- Ecologic France, 15 Avenue du Centre, Guyancour, 78280, France
| | - Qingyu Yan
- SCARCE Laboratory, Energy Research Institute @ NTU, Nanyang Technological University, Singapore, 639798, Singapore
- School of Material Science and Engineering, Nanyang Technological University, Singapore, 639798, Singapore
| | - Jean-Christophe P Gabriel
- SCARCE Laboratory, Energy Research Institute @ NTU, Nanyang Technological University, Singapore, 639798, Singapore
- Université Paris-Saclay, CEA, CNRS, NIMBE, LICSEN, Gif-sur-Yvette, 91191, France
| |
Collapse
|
3
|
Gómez M, Grimes S, Fowler G. Development of complete hydrometallurgical processes for gold recovery from ICs and CPUs using ionic liquids. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 362:121306. [PMID: 38833918 DOI: 10.1016/j.jenvman.2024.121306] [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: 01/03/2024] [Revised: 04/08/2024] [Accepted: 05/30/2024] [Indexed: 06/06/2024]
Abstract
Integrated circuits (ICs) and central processing units (CPUs), essential components of electrical and electronic equipment (EEE), are complex composite materials rich in recyclable high-value strategic and critical metals, with many in concentrations higher than in their natural ores. With gold the most valuable metal present, increase in demand for gold for EEE and its limited availability have led to a steep rise in the market price of gold, making gold recycling a high priority to meet demand. To overcome the limitations associated with conventional technologies for recycling e-waste, the use of greener technologies (ionic liquids (ILs) as leaching agents), offers greater potential for the recovery of gold from e-waste components. While previous studies have demonstrated the efficiency and feasibility of using ILs for gold recovery, these works predominantly concentrate on the extraction stage and often utilise simulated solutions, lacking the implementation of a complete process validated with real samples to effectively assess its overall effectiveness. In this work, a simulated Model Test System was used to determine the optimal leaching and extraction conditions before application to real samples. With copper being the most abundant metal in the e-waste fractions, to access the gold necessitated a two-stage pre-treatment (nitric acid leaching followed by aqua regia leaching) to ensure complete removal of copper and deliver a gold-enriched leach liquor. Gold extraction from the leach liquor was achieved by liquid-liquid extraction using Cyphos 101 (0.1 M in toluene with an O:A = 1:1, 20 °C, 150 rpm, and 15 min) and as a second process by sorption extraction with loaded resins (Amberlite XAD-7 with 300 mg of Cyphos 101/g of resins at 20 °C, 150 rpm and 3 h). In both processes, complete stripping and desorption of gold was achieved (0.5 M thiourea in 0.5 M HCl) and gold recovered, as nanoparticles of purity ≥95%, via a reduction step using a sodium borohydride solution (0.1 M NaBH4 in 0.1 M NaOH). These two hydrometallurgical processes developed can achieve overall efficiencies of ≥95% for gold recovery from real e-waste components, permit the reuse of the IL and resins up to five consecutive times, and offer a promising approach for recovery from any e-waste stream rich in gold.
Collapse
Affiliation(s)
- Moisés Gómez
- Department of Civil and Environmental Engineering, Imperial College London, South Kensington Campus, London, SW7 2AZ, United Kingdom.
| | - Sue Grimes
- Department of Civil and Environmental Engineering, Imperial College London, South Kensington Campus, London, SW7 2AZ, United Kingdom
| | - Geoff Fowler
- Department of Civil and Environmental Engineering, Imperial College London, South Kensington Campus, London, SW7 2AZ, United Kingdom
| |
Collapse
|
4
|
Andrianisa HA, Sossou SK, Zorom M, Nare L, Ahossouhe MS, Sanou A. An alternative classification approach for waste electronic and electrical equipment (WEEE) recovery in low-income countries: case study in Burkina Faso. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:39318-39330. [PMID: 38814561 DOI: 10.1007/s11356-024-33796-8] [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: 09/04/2023] [Accepted: 05/20/2024] [Indexed: 05/31/2024]
Abstract
Waste electrical and electronic equipment (WEEE) is defined as "urban mines" due to the various recoverable minerals they contain. However, current WEEE classification methods are mostly limited to their physical characteristics, focusing on collection, transport, and treatment purposes rather than on valorization. In the present study, our aim is to propose an alternative classification approach adapted for low-income countries for WEEE recovery that highlights their content of precious and valuable metals. A typology of WEEE was created based on WEEE generated in Ouagadougou (Burkina Faso). Principal component analysis (PCA) and the moving center technique (K-means) were used for the classification method. Ultimately, we have found that to improve the recovery of WEEE, they can be classified into three main groups: (i) a group of WEEE-containing batteries, (ii) a group of WEEE-containing valuable and precious metals, and finally, (iii) a group of WEEE made up of cathode ray tube televisions (CRT-TV) waste. The WEEE belonging to the second group are the ones that could generate higher economical values. This alternative classification approach will help investors and operators to better orient their valorization activities towards WEEE types that present the best precious metals recovery potential, maximizing their profits. On the other hand, decision-makers will find this classification useful for reorganizing the WEEE value chain.
Collapse
Affiliation(s)
- Harinaivo Anderson Andrianisa
- Laboratoire Eau, Hydro-Systèmes Et Agriculture (LEHSA), Institut International d'Ingénierie de L'Eau Et de L'Environnement (2iE), 01 BP 594, Ouagadougou, Burkina Faso
| | - Seyram Kossi Sossou
- Laboratoire Eau, Hydro-Systèmes Et Agriculture (LEHSA), Institut International d'Ingénierie de L'Eau Et de L'Environnement (2iE), 01 BP 594, Ouagadougou, Burkina Faso.
| | - Malicki Zorom
- Laboratoire Eau, Hydro-Systèmes Et Agriculture (LEHSA), Institut International d'Ingénierie de L'Eau Et de L'Environnement (2iE), 01 BP 594, Ouagadougou, Burkina Faso
| | - Landrine Nare
- Laboratoire Eau, Hydro-Systèmes Et Agriculture (LEHSA), Institut International d'Ingénierie de L'Eau Et de L'Environnement (2iE), 01 BP 594, Ouagadougou, Burkina Faso
| | - Mahugnon Samuel Ahossouhe
- Laboratoire Eau, Hydro-Systèmes Et Agriculture (LEHSA), Institut International d'Ingénierie de L'Eau Et de L'Environnement (2iE), 01 BP 594, Ouagadougou, Burkina Faso
| | - Alassane Sanou
- Association Burkinabe Pour La Promotion de L'Emploi Vert (ABPEV), Ouagadougou, Burkina Faso
| |
Collapse
|
5
|
Martins TAG, de Moraes VT, Espinosa DCR. Copper recovery by solvent extraction for nanoparticle synthesis from waste motherboards. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:39690-39703. [PMID: 38829502 DOI: 10.1007/s11356-024-33797-7] [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: 02/20/2024] [Accepted: 05/20/2024] [Indexed: 06/05/2024]
Abstract
Printed circuit boards, which make up part of waste from electrical and electronic equipment, contain elements that can be economically reused, such as copper, silver, gold, and nickel, as well as metals that are harmful to the environment and health, such as lead, mercury, and cadmium. Thus, through recycling this scrap, materials that would otherwise be discarded can be reinserted as secondary raw materials to produce new consumer goods through urban mining. In this context, the synthesis of nanoparticles shows promise as it allows the reinsertion of these materials in the manufacture of new products. Therefore, this study used obsolete computer motherboards as a secondary material to obtain copper to produce nanoparticles of this metal. From a solution based on the leach liquor of this scrap, a purification route using solvent extraction was defined and applied to the real leach liquor. Applying the hydroxyoxime extractant at a dilution of 20% (v/v) in kerosene, A/O of 1/1, 298 K, and 0.25 h of contact during extraction, and stripping in H2SO4 (2 M), 298 K, 0.25 h, W/O ratio of 3/1, and two theoretical countercurrent stages, a solution containing more than 95% of the copper in the leach liquor could be obtained with less than 1% of contaminants. From this purified liquor, nanoparticles containing copper and metallic copper oxides and hydroxides were produced, with an average size of 84 nm, at pH 11, 3 h of hot stirring, volume of 0.015 L of ascorbic acid (0.50 M) and 0.015 L of precursor solution (0.03 M Cu), and temperature (343 K).
Collapse
Affiliation(s)
| | - Viviane Tavares de Moraes
- Maua Institute of Technology, Praça Maua, 1 - Maua, Sao Caetano do Sul, CEP 09580-900, Sao Paulo, Brazil
| | - Denise Crocce Romano Espinosa
- Department of Chemical Engineering, Polytechnic School of the University of Sao Paulo (USP), Lago St., No. 250, CEP 05508-080, Sao Paulo, SP, Brazil
| |
Collapse
|
6
|
Cseresznye A, Hardy EM, Ait Bamai Y, Cleys P, Poma G, Malarvannan G, Scheepers PTJ, Viegas S, Martins C, Porras SP, Santonen T, Godderis L, Verdonck J, Poels K, João Silva M, Louro H, Martinsone I, Akūlova L, van Dael M, van Nieuwenhuyse A, Mahiout S, Duca RC, Covaci A. HBM4EU E-waste study: Assessing persistent organic pollutants in blood, silicone wristbands, and settled dust among E-waste recycling workers in Europe. ENVIRONMENTAL RESEARCH 2024; 250:118537. [PMID: 38408627 DOI: 10.1016/j.envres.2024.118537] [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: 01/06/2024] [Revised: 02/17/2024] [Accepted: 02/20/2024] [Indexed: 02/28/2024]
Abstract
E-waste recycling is an increasingly important activity that contributes to reducing the burden of end-of-life electronic and electrical apparatus and allows for the EU's transition to a circular economy. This study investigated the exposure levels of selected persistent organic pollutants (POPs) in workers from e-waste recycling facilities across Europe. The concentrations of seven polychlorinated biphenyls (PCBs) and eight polybrominated diphenyl ethers (PBDEs) congeners were measured by GC-MS. Workers were categorized into five groups based on the type of e-waste handled and two control groups. Generalized linear models were used to assess the determinants of exposure levels among workers. POPs levels were also assessed in dust and silicone wristbands (SWB) and compared with serum. Four PCB congeners (CB 118, 138, 153, and 180) were frequently detected in serum regardless of worker's category. With the exception of CB 118, all tested PCBs were significantly higher in workers compared to the control group. Controls working in the same company as occupationally exposed (Within control group), also displayed higher levels of serum CB 180 than non-industrial controls with no known exposures to these chemicals (Outwith controls) (p < 0.05). BDE 209 was the most prevalent POP in settled dust (16 μg/g) and SWB (220 ng/WB). Spearman correlation revealed moderate to strong positive correlations between SWB and dust. Increased age and the number of years smoked cigarettes were key determinants for workers exposure. Estimated daily intake through dust ingestion revealed that ΣPCB was higher for both the 50th (0.03 ng/kg bw/day) and 95th (0.09 ng/kg bw/day) percentile exposure scenarios compared to values reported for the general population. This study is one of the first to address the occupational exposure to PCBs and PBDEs in Europe among e-waste workers through biomonitoring combined with analysis of settled dust and SWB. Our findings suggest that e-waste workers may face elevated PCB exposure and that appropriate exposure assessments are needed to establish effective mitigation strategies.
Collapse
Affiliation(s)
- Adam Cseresznye
- Toxicological Centre, Department of Pharmaceutical Sciences, University of Antwerp, Antwerp, Belgium
| | - Emilie M Hardy
- Environmental Hygiene and Human Biological Monitoring, Department of Health Protection, Laboratoire National de Santé (LNS), Luxembourg, Luxembourg
| | - Yu Ait Bamai
- Toxicological Centre, Department of Pharmaceutical Sciences, University of Antwerp, Antwerp, Belgium; Center for Environmental and Health Sciences, Hokkaido University, Sapporo, Japan
| | - Paulien Cleys
- Toxicological Centre, Department of Pharmaceutical Sciences, University of Antwerp, Antwerp, Belgium
| | - Giulia Poma
- Toxicological Centre, Department of Pharmaceutical Sciences, University of Antwerp, Antwerp, Belgium
| | - Govindan Malarvannan
- Toxicological Centre, Department of Pharmaceutical Sciences, University of Antwerp, Antwerp, Belgium
| | - Paul T J Scheepers
- Radboud Institute for Biological and Environmental Sciences, Radboud University, Nijmegen, the Netherlands
| | - Susana Viegas
- Comprehensive Health Research Center, NOVA National School of Public Health, Public Health Research Centre, NOVA University Lisbon, Lisbon, Portugal
| | - Carla Martins
- Comprehensive Health Research Center, NOVA National School of Public Health, Public Health Research Centre, NOVA University Lisbon, Lisbon, Portugal
| | - Simo P Porras
- Finnish Institute of Occupational Health, Helsinki, Finland
| | - Tiina Santonen
- Finnish Institute of Occupational Health, Helsinki, Finland
| | - Lode Godderis
- Environment and Health, Department of Public Health and Primary Care, KU Leuven, Leuven, Belgium; Idewe, External Service for Prevention and Protection at Work, Heverlee, Belgium
| | - Jelle Verdonck
- Environment and Health, Department of Public Health and Primary Care, KU Leuven, Leuven, Belgium
| | - Katrien Poels
- Environment and Health, Department of Public Health and Primary Care, KU Leuven, Leuven, Belgium
| | - Maria João Silva
- ToxOmics -Centre for Toxicogenomics and Human Health, Department of Human Genetics, National Institute of Health Dr. Ricardo Jorge (INSA), NOVA Medical School, Lisbon, Portugal
| | - Henriqueta Louro
- ToxOmics -Centre for Toxicogenomics and Human Health, Department of Human Genetics, National Institute of Health Dr. Ricardo Jorge (INSA), NOVA Medical School, Lisbon, Portugal
| | - Inese Martinsone
- Institute of Occupational Safety and Environmental Health, Rīgas Stradiņš University, Riga, Latvia
| | - Lāsma Akūlova
- Institute of Occupational Safety and Environmental Health, Rīgas Stradiņš University, Riga, Latvia
| | - Maurice van Dael
- Radboud Institute for Biological and Environmental Sciences, Radboud University, Nijmegen, the Netherlands
| | - An van Nieuwenhuyse
- Environmental Hygiene and Human Biological Monitoring, Department of Health Protection, Laboratoire National de Santé (LNS), Luxembourg, Luxembourg; Environment and Health, Department of Public Health and Primary Care, KU Leuven, Leuven, Belgium
| | - Selma Mahiout
- Finnish Institute of Occupational Health, Helsinki, Finland
| | - Radu Corneliu Duca
- Environmental Hygiene and Human Biological Monitoring, Department of Health Protection, Laboratoire National de Santé (LNS), Luxembourg, Luxembourg; Environment and Health, Department of Public Health and Primary Care, KU Leuven, Leuven, Belgium
| | - Adrian Covaci
- Toxicological Centre, Department of Pharmaceutical Sciences, University of Antwerp, Antwerp, Belgium.
| |
Collapse
|
7
|
Hasan MM, Mahmud TS, Assuah A, Ng KTW, Tasnim A, Abha AT. An investigation on the operational resilience of the Canadian electronic product stewardship program and the recycling business characteristics. WASTE MANAGEMENT (NEW YORK, N.Y.) 2024; 181:68-78. [PMID: 38593732 DOI: 10.1016/j.wasman.2024.04.002] [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: 10/26/2023] [Revised: 03/13/2024] [Accepted: 04/01/2024] [Indexed: 04/11/2024]
Abstract
Electronic waste recycling companies have proliferated in many countries due to valuable materials present in end-of-life electronic and electrical equipment. This article examined the business characteristics and management performance of Electronic Products Recycling Association (EPRA), a Canadian nationwide electronic product stewardship organization. The organization's annual performance reports, from 2012 to 2020, for nine Canadian provinces in which it currently operates were aggregated and analyzed. Temporal analysis using regression and Mann-Kendall tests were employed, and five characteristics of EPRA's business were analyzed, including e-waste products collected, number of drop-off locations, efforts to build public awareness, operating expenses, and growth of e-waste stewardship. Results show a decline in the amount of e-waste collected across the provinces, except in New Brunswick, which started its program in 2017. The Mann-Kendall test revealed declining temporal trends in most provinces. Although the collection/drop off sites and stewardship organizations increased astronomically over the study period in Canada, the amounts of e-waste collected decreased. We found that public awareness generally did not increase the amount of e-waste collected, and these campaigns only appeared to be effective in jurisdictions with good accessibility of e-waste recycling. Processing cost accounted for the majority of the e-waste management budget in Canada, and different factors affected the financial success of the stewards differently.
Collapse
Affiliation(s)
- Mohammad Mehedi Hasan
- Environmental Systems Engineering, 3737 Wascana Parkway, Regina, Saskatchewan S4S 0A2, Canada.
| | - Tanvir Shahrier Mahmud
- Environmental Systems Engineering, 3737 Wascana Parkway, Regina, Saskatchewan S4S 0A2, Canada.
| | - Anderson Assuah
- University College of the North, 7th Street East, The Pas, Manitoba R9A 1M7, Canada.
| | - Kelvin Tsun Wai Ng
- Environmental Systems Engineering, 3737 Wascana Parkway, Regina, Saskatchewan S4S 0A2, Canada.
| | - Anica Tasnim
- Environmental Systems Engineering, 3737 Wascana Parkway, Regina, Saskatchewan S4S 0A2, Canada.
| | - Anika Tahsin Abha
- Environmental Systems Engineering, 3737 Wascana Parkway, Regina, Saskatchewan S4S 0A2, Canada.
| |
Collapse
|
8
|
Vance SM, Mojsak M, Kinsman LMM, Rae R, Kirk C, Love JB, Morrison CA. Selective Gold Precipitation by a Tertiary Diamide Driven by Thermodynamic Control. Inorg Chem 2024; 63:9332-9345. [PMID: 38722710 PMCID: PMC11110006 DOI: 10.1021/acs.inorgchem.4c01279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2024] [Revised: 04/26/2024] [Accepted: 04/30/2024] [Indexed: 05/21/2024]
Abstract
The simple diamide ligand L was previously shown to selectively precipitate gold from acidic solutions typical of e-waste leach streams, with precipitation of gallium, iron, tin, and platinum possible under more forcing conditions. Herein, we report direct competition experiments to afford the order of selectivity. Thermal analysis indicates that the gold-, gallium-, and iron-containing precipitates present as the most thermodynamically stable structures at room temperature, while the tin-containing structure does not. Computational modeling established that the precipitation process is thermodynamically driven, with ion exchange calculations matching the observed experimental selectivity ordering. Calculations also show that the stretched ligand conformation seen in the X-ray crystal structure of the gold-containing precipitate is more strained than in the structures of the other metal precipitates, indicating that intermolecular interactions likely dictate the selectivity ordering. This was confirmed through a combination of Hirshfeld, noncovalent interaction (NCI), and quantum theory of atoms in molecules (QTAIM) analyses, which highlight favorable halogen···halogen contacts between metalates and pseudo-anagostic C-H···metal interactions in the crystal structure of the gold-containing precipitate.
Collapse
Affiliation(s)
- Susanna
S. M. Vance
- EaStCHEM School of Chemistry, University of Edinburgh, Edinburgh EH9 3FJ, United Kingdom
| | - Mateusz Mojsak
- EaStCHEM School of Chemistry, University of Edinburgh, Edinburgh EH9 3FJ, United Kingdom
| | - Luke M. M. Kinsman
- EaStCHEM School of Chemistry, University of Edinburgh, Edinburgh EH9 3FJ, United Kingdom
| | - Rebecca Rae
- EaStCHEM School of Chemistry, University of Edinburgh, Edinburgh EH9 3FJ, United Kingdom
| | - Caroline Kirk
- EaStCHEM School of Chemistry, University of Edinburgh, Edinburgh EH9 3FJ, United Kingdom
| | - Jason B. Love
- EaStCHEM School of Chemistry, University of Edinburgh, Edinburgh EH9 3FJ, United Kingdom
| | - Carole A. Morrison
- EaStCHEM School of Chemistry, University of Edinburgh, Edinburgh EH9 3FJ, United Kingdom
| |
Collapse
|
9
|
Vuppaladadiyam SSV, Thomas BS, Kundu C, Vuppaladadiyam AK, Duan H, Bhattacharya S. Can e-waste recycling provide a solution to the scarcity of rare earth metals? An overview of e-waste recycling methods. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 924:171453. [PMID: 38453089 DOI: 10.1016/j.scitotenv.2024.171453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 02/27/2024] [Accepted: 03/01/2024] [Indexed: 03/09/2024]
Abstract
Recycling e-waste is seen as a sustainable alternative to compensate for the limited natural rare earth elements (REEs) resources and the difficulty of accessing these resources. Recycling facilitates the recovery of valuable products and minimizes emissions during their transportation. Numerous studies have been reported on e-waste recycling using various techniques, including thermo-, hydro- and biometallurgical approaches. However, each approach still has technical, economic, social, or environmental limitations. This review highlights the potential of recycling e-waste, including outlining the current unutilized potential of REE recycling from different e-waste components. An in-depth analysis of e-waste generation on a global scale and Australian scenario, along with various hazardous impacts on ecosystem and human health, is reported. In addition, a comprehensive summary of various metal recovery processes and their merits and demerits is also presented. Lifecycle analysis for recovering REEs from e-waste indicate a positive environmental impact when compared to REEs produced from virgin sources. In addition, recovering REEs form secondary sources eliminated ca. 1.5 times radioactive waste, as seen in production from primary sources scenario. The review outcome demonstrates the increasing potential of REE recycling to overcome critical challenges, including issues over supply security and localized dependency.
Collapse
Affiliation(s)
| | - Bennet Sam Thomas
- Department of Chemical and Biological Engineering, Monash University, Australia
| | - Chandan Kundu
- Department of Chemical and Biological Engineering, Monash University, Australia
| | | | - Huabo Duan
- School of Environmental Science and Engineering, Huazhong University of Science and Technology (HUST), Wuhan 430074, China
| | - Sankar Bhattacharya
- Department of Chemical and Biological Engineering, Monash University, Australia.
| |
Collapse
|
10
|
Kaur A, Alarco J, Mullane APO. Investigating the Potential Use of Ni-Mn-Co (NMC) Battery Materials as Electrocatalysts for Electrochemical Water Splitting. Chemphyschem 2024:e202400124. [PMID: 38651214 DOI: 10.1002/cphc.202400124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2024] [Revised: 04/21/2024] [Accepted: 04/22/2024] [Indexed: 04/25/2024]
Abstract
The imminent generation of significant amounts of Li ion battery waste is of concern due to potential detrimental environmental impacts. However, this also poses an opportunity to recycle valuable battery materials for later use. One underexplored area is using commonly employed cathode materials such as nickel, manganese cobalt (NMC) oxide as an electrocatalyst for water splitting reactions. In this work we explore the possibility of using NMC materials of different metallic ratios (NMC 622 and 811) as oxygen evolution and hydrogen evolution catalysts under alkaline conditions. We show that both materials are excellent oxygen evolution reaction (OER) electrocatalysts but perform poorly for the hydrogen evolution reaction. NMC 622 demonstrates the better OER activity with an overpotential of only 280 mV to pass 100 mA cm-2 and a low tafel slope of 42 mV dec-1. The material can also pass high current densities of 150 mA cm-2 for 24 h while also being tolerant to extensive potential cycling indicating suitability for direct integration with renewable energy inputs. This work demonstrates that NMC cathode materials if recovered from Li ion batteries are suitable OER electrocatalysts.
Collapse
Affiliation(s)
- Arshdeep Kaur
- School of of Chemistry and Physics, Queensland University of Technology (QUT), Brisbane, QLD, 4001, Australia
- Centre for Materials Science, Queensland University of Technology (QUT), Brisbane, QLD, 4001, Australia
| | - Jose Alarco
- School of of Chemistry and Physics, Queensland University of Technology (QUT), Brisbane, QLD, 4001, Australia
- Centre for Materials Science, Queensland University of Technology (QUT), Brisbane, QLD, 4001, Australia
| | - Anthony P O' Mullane
- School of of Chemistry and Physics, Queensland University of Technology (QUT), Brisbane, QLD, 4001, Australia
- Centre for Materials Science, Queensland University of Technology (QUT), Brisbane, QLD, 4001, Australia
| |
Collapse
|
11
|
Koskinen J, Frimodig J, Samulinen M, Tiihonen A, Siljanto J, Haukka M, Väisänen A. Optimization of Selective Hydrometallurgical Tantalum Recovery from E-Waste Using Zeolites. ACS OMEGA 2024; 9:14947-14954. [PMID: 38585115 PMCID: PMC10993384 DOI: 10.1021/acsomega.3c08907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 02/20/2024] [Accepted: 03/08/2024] [Indexed: 04/09/2024]
Abstract
To protect future high-tech metal demand, a selective and efficient recovery method for tantalum from a tantalum-rich e-waste component sample was developed. Ultrasound-assisted digestion of the component sample was optimized, and the highest dissolution rate was achieved using a mixture of 8 mol/L H2SO4 and HF at a temperature of 60 °C. The determined amount of tantalum was as high as 11 000 ± 1000 mg/kg, which results in a high potential for recyclable tantalum. The other major elements of this complex e-waste fraction were silicon, iron, aluminum, and tin. Efficient recovery of tantalum from the leachate was performed using the zeolite material ZSM-5. Extremely high selectivity and a recovery rate of over 98% were obtained. In terms of adsorption efficiency, selectivity, and durability of the material, optimal adsorption was obtained using the diluted sample at 0.5 mol/L of H2SO4. The adsorption capacity of ZSM-5 for tantalum was determined to be 10.5 ± 0.6 mg/g, and tantalum was selectively eluted with 1:4 diluted ethanolamine with a yield of 87.2 ± 1.5%.
Collapse
Affiliation(s)
- Jutta Koskinen
- Department
of Chemistry, University of Jyväskylä, P.O. Box 35, Jyväskylä FI-40014, Finland
| | - Janne Frimodig
- Department
of Chemistry, University of Jyväskylä, P.O. Box 35, Jyväskylä FI-40014, Finland
| | | | - Antti Tiihonen
- Department
of Chemistry, University of Jyväskylä, P.O. Box 35, Jyväskylä FI-40014, Finland
| | - Jimi Siljanto
- Department
of Chemistry, University of Jyväskylä, P.O. Box 35, Jyväskylä FI-40014, Finland
| | - Matti Haukka
- Department
of Chemistry, University of Jyväskylä, P.O. Box 35, Jyväskylä FI-40014, Finland
| | - Ari Väisänen
- Department
of Chemistry, University of Jyväskylä, P.O. Box 35, Jyväskylä FI-40014, Finland
| |
Collapse
|
12
|
Rahimi V, Inzulza-Moraga EA, Gómez-Díaz D, Freire MS, González-Álvarez J. Screening of variables affecting the selective leaching of valuable metals from waste motherboards' PCBs. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024:10.1007/s11356-024-32793-1. [PMID: 38460042 DOI: 10.1007/s11356-024-32793-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Accepted: 03/02/2024] [Indexed: 03/11/2024]
Abstract
The presence of valuable and hazardous metals in waste printed circuit boards, especially, motherboards, makes their recovery necessary as implies great economic and environmental advantages and develops urban mining processes. Hence, this research is focused on the selective leaching of Cu, Pb, and Sn as base metals using nitric acid and hydrochloric acid and Au, Ag, and Pd as precious metals using thiourea and sodium thiosulfate from waste motherboards' PCBs in a sequential eco-friendly two-stage process. Previously, thiourea and sodium thiosulfate were used as leaching agents to investigate their applicability for the leaching of metals from PCBs in a single-stage process. Screening experimental design was applied to screen the variables affecting the leaching process in order to evaluate their impact on the recovery of metals and select the significant factors. The results demonstrated that base and precious metals can be leached appropriately in two consecutive stages compared to a single-stage process. Nitric acid was found to be a much more efficient agent to leach Cu and Pb in comparison with hydrochloric acid which was more suitable for the leaching of Sn. In the case of precious metals, higher amounts of Au were leached using thiourea, whereas sodium thiosulfate was able to leach more Pd. Roughly similar results were obtained for the leaching of Ag using these leaching agents. Nitric acid concentration, average particle size, temperature, and leaching time were found to be significant to maximize the leaching of Cu and Pb and minimize that for Au, Ag, and Pd in the first stage. Initial pH was the only variable influencing the second stage, in particular, Au leaching by thiourea.
Collapse
Affiliation(s)
- Vahid Rahimi
- Department of Chemical Engineering, School of Engineering, Universidade de Santiago de Compostela, Rúa Lope Gómez de Marzoa s/n, 15782, Santiago de Compostela, Spain
| | - Emilio Antonio Inzulza-Moraga
- Department of Chemical Engineering, School of Engineering, Universidade de Santiago de Compostela, Rúa Lope Gómez de Marzoa s/n, 15782, Santiago de Compostela, Spain
| | - Diego Gómez-Díaz
- Department of Chemical Engineering, School of Engineering, Universidade de Santiago de Compostela, Rúa Lope Gómez de Marzoa s/n, 15782, Santiago de Compostela, Spain
| | - María Sonia Freire
- Department of Chemical Engineering, School of Engineering, Universidade de Santiago de Compostela, Rúa Lope Gómez de Marzoa s/n, 15782, Santiago de Compostela, Spain
| | - Julia González-Álvarez
- Department of Chemical Engineering, School of Engineering, Universidade de Santiago de Compostela, Rúa Lope Gómez de Marzoa s/n, 15782, Santiago de Compostela, Spain.
| |
Collapse
|
13
|
Chen C, Duan C, Zou F, Li J, Yan K. Multifunctionally Reusing Waste Solder to Prepare Highly Efficient Sn-Pb Perovskite Solar Cells. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024:e2312265. [PMID: 38415951 DOI: 10.1002/smll.202312265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Revised: 02/13/2024] [Indexed: 02/29/2024]
Abstract
The preparation of perovskite components (PbI2 and SnI2 ) using waste materials is of great significance for the commercialization of perovskite solar cells (PSCs). However, this goal is difficult to achieve due to the purity of the recovered products and the easy oxidation of Sn2+ . Here, a simple one-step synthetic process to convert waste Sn-Pb solder into SnI2 /PbI2 and then applied as-prepared SnI2 /PbI2 to PSCs for high additional value is adopted. During fabrication, Sn-Pb waste solder is also employed to serve as a reducing agent to reduce the Sn4+ in Sn-Pb mixed narrow perovskite precursor and hence remove the deep trap states in perovskite. The target PSCs achieved an efficiency of 21.04%, which is better than the efficiency of the device with commercial SnI2 /PbI2 (20.10%). Meanwhile, the target PSC maintained an initial efficiency of 80% even after 800 h under continuous illumination, which is significantly better than commercial devices. In addition, the method achieved a recovery rate of 90.12% for Sn-Pb waste solder, with a lab-grade purity (over 99.8%) for SnI2 /PbI2 , and the cost of perovskite active layer reduced to 39.81% through this recycling strategy through calculation.
Collapse
Affiliation(s)
- Chang Chen
- School of Environment and Energy, State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, South China University of Technology, Guangzhou, 510000, China
| | - Chenghao Duan
- School of Environment and Energy, State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, South China University of Technology, Guangzhou, 510000, China
| | - Feilin Zou
- School of Environment and Energy, State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, South China University of Technology, Guangzhou, 510000, China
| | - Jiong Li
- School of Environment and Energy, State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, South China University of Technology, Guangzhou, 510000, China
| | - Keyou Yan
- School of Environment and Energy, State Key Laboratory of Luminescent Materials and Devices, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, South China University of Technology, Guangzhou, 510000, China
| |
Collapse
|
14
|
Zhang R, Zhang X, Zhang Q, Li Y, Wang Y, Xu J, Cheng Z, Chen H, Yao Y, Sun H. Heterogeneous Photodegradation Behavior of Liquid Crystal Monomers in Dust: Quantitative Structure-Activity Relationship and Product Identification. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:3908-3918. [PMID: 38329000 DOI: 10.1021/acs.est.3c04753] [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: 02/09/2024]
Abstract
The heterogeneous photodegradation behavior of liquid crystal monomers (LCMs) in standard dust (standard reference material, SRM 2583) and environmental dust was investigated. The measured photodegradation ratios for 23 LCMs in SRM and environmental dust in 12 h were 11.1 ± 1.8 to 23.2 ± 1.1% and 8.7 ± 0.5 to 24.0 ± 2.8%, respectively. The degradation behavior of different LCM compounds varied depending on their structural properties. A quantitative structure-activity relationship model for predicting the degradation ratio of LCMs in SRM dust was established, which revealed that the molecular descriptors related to molecular polarizability, electronegativity, and molecular mass were closely associated with LCMs' photodegradation. The photodegradation products of the LCM compound 4'-propoxy-4-biphenylcarbonitrile (PBIPHCN) in dust, including •OH oxidation, C-O bond cleavage, and ring-opening products, were identified by nontarget analysis, and the corresponding degradation pathways were suggested. Some of the identified products, such as 4'-hydroxyethoxy-4-biphenylcarbonitrile, showed predicted toxicity (with an oral rat lethal dose of 50%) comparable to that of PBIPHCN. The half-lives of the studied LCMs in SRM dust were estimated at 32.2-82.5 h by fitting an exponential decay curve to the observed photodegradation data. The photodegradation mechanisms of LCMs in dust were revealed for the first time, enhancing the understanding of LCMs' environmental behavior and risks.
Collapse
Affiliation(s)
- Ruiqi Zhang
- School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, China
- MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, 38 Tongyan Road, Jinnan District, Tianjin 300350, China
| | - Xiao Zhang
- School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, China
| | - Qiuyue Zhang
- MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, 38 Tongyan Road, Jinnan District, Tianjin 300350, China
| | - Yongcheng Li
- MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, 38 Tongyan Road, Jinnan District, Tianjin 300350, China
| | - Yu Wang
- MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, 38 Tongyan Road, Jinnan District, Tianjin 300350, China
| | - Jiaping Xu
- MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, 38 Tongyan Road, Jinnan District, Tianjin 300350, China
| | - Zhipeng Cheng
- MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, 38 Tongyan Road, Jinnan District, Tianjin 300350, China
| | - Hao Chen
- MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, 38 Tongyan Road, Jinnan District, Tianjin 300350, China
| | - Yiming Yao
- MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, 38 Tongyan Road, Jinnan District, Tianjin 300350, China
| | - Hongwen Sun
- MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, 38 Tongyan Road, Jinnan District, Tianjin 300350, China
| |
Collapse
|
15
|
Razavian Tabari SR, Salahinejad E. Selective recovery of gold and silver from electronic wastes through a sequential process of Qalkari and room-temperature hydrometallurgy. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 351:119778. [PMID: 38086113 DOI: 10.1016/j.jenvman.2023.119778] [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: 08/01/2023] [Revised: 11/16/2023] [Accepted: 12/03/2023] [Indexed: 01/14/2024]
Abstract
This work was focused on the selective recovery of gold and silver from electronic wastes using a sequential process of pyrometallurgy (Qalkari) and room-temperature hydrometallurgy. In the first step, electronic wastes underwent Qalkari recycling, yielding tablets containing precious elements (Qalkari furnace product) and melting slag (Qalkari furnace waste). In the subsequent hydrometallurgy phase, the nitric acid concentration and the input solid amount were optimized for the effective room-temperature recovery of gold. Due to the successful separation of precision elements and disturbing substances in Qalkari, the gold recovery efficiency of 99.99% was obtained at the acid concentration of 50% (v/v) and the solid input of 15% (w/v). Afterwards, HCl, NH4Cl, and NaCl were used for silver recovery from the Qalkari-processed gold-recovered leaching solution, leading to the efficiency of 99.99%. But NH4Cl was recognized as the most effective precipitant as it promises the most enhanced potential for the possible subsequent recovery of palladium. In conclusion, this study draws the effectiveness of Qalkari in recycling electronic wastes, with a significant impact on the efficiency of succeeding room-temperature hydrometallurgical processes for gold and silver recovery within a reasonable leaching time.
Collapse
Affiliation(s)
| | - Erfan Salahinejad
- Faculty of Materials Science and Engineering, K. N. Toosi University of Technology, Tehran, Iran.
| |
Collapse
|
16
|
Wu Y, Qi H, Zhang Y, Xie H. 'Gold' lost in restoration: Evaluation of core morphology of custom metal posts and cores, and analysis of precious metal debris. Heliyon 2024; 10:e24946. [PMID: 38312696 PMCID: PMC10835304 DOI: 10.1016/j.heliyon.2024.e24946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 01/16/2024] [Accepted: 01/17/2024] [Indexed: 02/06/2024] Open
Abstract
1 Objectives To investigate the deviations between the morphological dimensions of finished cores and desired dimensions made by three available fabricating techniques. To assess the precious metal loss in custom precious metal post and core restorative treatment in the dental clinic. 2 Methods Titanium posts and cores were fabricated using three different techniques: digital scanning impression technology, digital scanning wax-pattern technology, and the traditional lost-wax casting method. Geomagic Studio was used to fit the scanned model data to the digital design data of the expected preparation and to analyze the 3D deviations between the two. Precious metal debris from the precious metal post and core was collected, processed, weighed and analyzed for precious metal elements by energy-dispersive X-ray spectroscopy layered images. 3 Results In all 48 pairs of models, there were positive and negative deviations, with the largest mean positive deviation of (0.752 ± 0.037 mm) for models made by the semi-digital scanning wax-pattern technique. A total of 7001.3 mg of metals was recovered from the waste streams collected, which contained precious metals-mainly gold, silver, and platinum. 4 Conclusions There were discrepancies between the custom core and the expected preparation regardless of the fabrication process used. The digital scanning impression technology showed better dimensional rationality of crown cores. Custom precious metal posts and cores can have an average precious metal loss of 129.7 mg per case in the dental clinic.
Collapse
Affiliation(s)
- Yumin Wu
- Department of Prosthodontics, The Affiliated Stomatological Hospital of Nanjing Medical University, Jiangsu Province Key Laboratory of Oral Diseases, Jiangsu Province Engineering Research Center of Stomatological Translational Medicine, Nanjing, 210029, China
| | - Haowen Qi
- Department of Prosthodontics, The Affiliated Stomatological Hospital of Nanjing Medical University, Jiangsu Province Key Laboratory of Oral Diseases, Jiangsu Province Engineering Research Center of Stomatological Translational Medicine, Nanjing, 210029, China
| | - Yuhang Zhang
- Digital Center, The Affiliated Stomatological Hospital of Nanjing Medical University, Jiangsu Province Key Laboratory of Oral Diseases, Jiangsu Province Engineering Research Center of Stomatological Translational Medicine, Nanjing, 210029, China
| | - Haifeng Xie
- Department of Prosthodontics, The Affiliated Stomatological Hospital of Nanjing Medical University, Jiangsu Province Key Laboratory of Oral Diseases, Jiangsu Province Engineering Research Center of Stomatological Translational Medicine, Nanjing, 210029, China
| |
Collapse
|
17
|
Mishra S, Hunter TN, Pant KK, Harbottle D. Green Deep Eutectic Solvents (DESs) for Sustainable Metal Recovery from Thermally Treated PCBs: A Greener Alternative to Conventional Methods. CHEMSUSCHEM 2024:e202301418. [PMID: 38189582 DOI: 10.1002/cssc.202301418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 12/26/2023] [Accepted: 01/05/2024] [Indexed: 01/09/2024]
Abstract
Waste PCBs the core of e-waste is rich in copper, tin, zinc, iron, and nickel. Leaching base metals from PCB used to be done in toxic, corrosive acidic/alkali mediums. In this work, an environmentally friendly method for leaching metals from thermally treated PCBs (TPCBs) of mobile phones was proposed using choline chloride based deep eutectic solvents (DES). DES selectivity and solubility of metals from metal oxides were the main screening criteria. FA-ChCl had the maximum solubility of Cu, Fe, and Ni, while Urea-ChCl had high Zn selectivity and solubility. Oxalic acid has high selectivity for Sn. FA-ChCl extracted Cu and Fe best at 16 h, 100 °C, and 1/30 g/mL. Urea-ChCl extracted Zn (90.4±2.9 %) from TPCBs at 100 °C, 21 h, 1/20 g/mL, and 400 rpm. Oxalic acid (1 M) removed 92.3±2.1 % Sn from TPCBs in 1 h at 80 °C and 1/20 g/mL. The shrinking core model-based kinetic investigation of FA-ChCl for Cu extraction showed a diffusion-controlled process. The proposed method is greener than mineral acids utilized for metal extraction.
Collapse
Affiliation(s)
- Snigdha Mishra
- Green and Sustainable Engineering Lab, Department of Chemical Engineering, IIT Delhi, Hauz Khaz, Delhi, 110016, India
- School of Chemical and Process Engineering, University of Leeds, Leeds, LS29JT, United Kingdom
| | - T N Hunter
- School of Chemical and Process Engineering, University of Leeds, Leeds, LS29JT, United Kingdom
| | - K K Pant
- Green and Sustainable Engineering Lab, Department of Chemical Engineering, IIT Delhi, Hauz Khaz, Delhi, 110016, India
- Department of Chemical Engineering, IIT Roorkee, Roorkee, 247667, India
| | - David Harbottle
- School of Chemical and Process Engineering, University of Leeds, Leeds, LS29JT, United Kingdom
| |
Collapse
|
18
|
Todee B, Sanae P, Ruengsuk A, Janthakit P, Promarak V, Tantirungrotechai J, Sukwattanasinitt M, Limpanuparb T, Harding DJ, Bunchuay T. Switchable Metal-Ion Selectivity in Sulfur-Functionalised Pillar[5]arenes and Their Host-Guest Complexes. Chem Asian J 2024; 19:e202300913. [PMID: 37971488 DOI: 10.1002/asia.202300913] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2023] [Revised: 11/15/2023] [Accepted: 11/16/2023] [Indexed: 11/19/2023]
Abstract
Nucleophilic substitution of pertosylated pillar[5]arene (P-OTs) with commercially available sulfur containing nucleophiles (KSCN, KSAc, and thiophenol), yields a series of sulfur-functionalised pillar[5]arenes. DLS results and SEM images imply that these pillararene macrocycles self-assemble in acetonitrile solution, while X-ray crystallographic evidence suggests solvent-dependent assembly in the solid state. The nature of the sulfur substituents decorating the rim of the pillararene controls binding affinities towards organic guest encapsulations within the cavity and dictates metal-ion binding properties through the formation of favorable S-M2+ coordination bonds outside the cavity, as determined by 1 H NMR and fluorescence spectroscopic experiments. Addition of a dinitrile guest containing a bis-triazole benzene spacer (btn) induced formation of pseudorotaxane host-guest complexes. Fluorescence emission signals from these discrete macrocycles were significantly attenuated in the presence of either Hg2+ or Cu2+ in solution. Analogous titrations utilizing the corresponding pseudorotaxanes alter the binding selectivity and improve fluorescence sensing sensitivity. In addition, preliminary liquid-liquid extraction studies indicate that the macrocycles facilitate the transfer of Cu2+ from the aqueous to the organic phase in comparison to extraction without pillar[5]arene ligands.
Collapse
Affiliation(s)
- Bunyaporn Todee
- Department of Chemistry and Center of Excellence for Innovation in Chemistry (PERCH-CIC), Faculty of Sciense, Mahidol University, Bangkok, 10400, Thailand
| | - Patharaporn Sanae
- Department of Chemistry and Center of Excellence for Innovation in Chemistry (PERCH-CIC), Faculty of Sciense, Mahidol University, Bangkok, 10400, Thailand
| | - Araya Ruengsuk
- Department of Chemistry and Center of Excellence for Innovation in Chemistry (PERCH-CIC), Faculty of Sciense, Mahidol University, Bangkok, 10400, Thailand
| | - Pattarapapa Janthakit
- Department of Materials Science and Engineering, School of Molecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology (VISTEC), Rayong, 21210, Thailand
| | - Vinich Promarak
- Department of Materials Science and Engineering, School of Molecular Science and Engineering, Vidyasirimedhi Institute of Science and Technology (VISTEC), Rayong, 21210, Thailand
| | - Jonggol Tantirungrotechai
- Department of Chemistry and Center of Excellence for Innovation in Chemistry (PERCH-CIC), Faculty of Sciense, Mahidol University, Bangkok, 10400, Thailand
| | | | - Taweetham Limpanuparb
- Science Division, Mahidol University International College, Mahidol University, Salaya, 73170, Thailand
| | - David J Harding
- Department of Chemistry, Institute of Science, Suranaree University of Technology, Nakhon Ratchasima, 30000, Thailand
| | - Thanthapatra Bunchuay
- Department of Chemistry and Center of Excellence for Innovation in Chemistry (PERCH-CIC), Faculty of Sciense, Mahidol University, Bangkok, 10400, Thailand
| |
Collapse
|
19
|
Chen Z, Zhan L, Xu Z. Enhancing Debromination Efficiency through Introducing Water Vapor Atmosphere to Overcome Limitations of Conventional Pyrolysis. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:20941-20950. [PMID: 38032848 DOI: 10.1021/acs.est.3c06640] [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: 12/02/2023]
Abstract
Bromine removal is significant in the recycling of waste printed circuit boards (WPCBs). This study found that the critical factors limiting the debromination efficiency of conventional pyrolysis are the formation of coke impeding mass transfer and conversion of bromine into less volatile species, such as coking-Br and copper bromide. According to frontier molecular orbital analysis and thermodynamic equilibrium analysis, C-O bonds of resin are sites prone to electrophilic reactions and copper bromide in residue may undergo hydrolysis; therefore, introducing H2O during pyrolysis was a feasible method for thorough debromination. Through pyrolysis in a water vapor atmosphere, the diffusion limitation of debromination was overcome, and resin was converted into light components; thereby, rapid and deep removal of bromine was achieved. The result indicated that 99.7% of bromine was removed, and the residue could be used as a clean secondary resource. According to life-cycle assessment, pyrolysis of WPCBs in water vapor could be expected to reduce 77 Kt of CO2 emission and increase financial benefits by 60 million dollars, annually.
Collapse
Affiliation(s)
- Zhenyu Chen
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China
| | - Lu Zhan
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China
| | - Zhenming Xu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China
| |
Collapse
|
20
|
Zhan Y, Jin Q, Lin H, Tao D, Law LY, Sun J, He Y. Occurrence, behavior and fate of liquid crystal monomers in municipal wastewater. WATER RESEARCH 2023; 247:120784. [PMID: 37950950 DOI: 10.1016/j.watres.2023.120784] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2023] [Revised: 10/20/2023] [Accepted: 10/23/2023] [Indexed: 11/13/2023]
Abstract
Liquid crystal monomers (LCMs), the essential substances used in the display screen of electronic devices, have been proposed as a class of emerging chemicals of concern. Despite their detection in various environmental matrices, little is known about the presence of LCMs in municipal sewage systems. This study aimed to investigate the occurrence, distribution, and fate of 64 LCMs released into the aqueous environment from a municipal wastewater treatment plant (WWTP) in Hong Kong, China. In total 14 LCMs were detected in WWTP samples. Specifically, the Σ14LCMs concentrations in crude influent, final effluent, and final sludge were found to be 16.8 ± 0.3 ng/L, 2.71 ± 0.05 ng/L, and 19.2 ± 1.0 ng/g dry weight, respectively. Among them, 10 fluorinated LCMs (F-LCMs) were determined to be present at concentrations of 8.90 ± 0.10 ng/L, 1.69 ± 0.05 ng/L, and 9.94 ± 1.00 ng/g dry weight, respectively. The predominant non-fluorinated LCMs (NF-LCMs) detected in all samples were 3OCB and EPhEMOB, while 2OdF3B was the dominant F-LCM. The overall removal rate of total LCMs was 83.8 ± 0.3 %, with 25.4 ± 4.8 % being removed by biodegradation and UV treatment. Compared to NF-LCMs, F-LCMs were more resistant to biodegradation. Despite the significant removal of LCMs through WWTP, the remaining LCMs in final effluent could result in an annual emission of 3.04 kg of total LCMs from the population of Hong Kong. This study provides the first evidence of LCMs contamination in municipal wastewater, possibly arising from routine electronic devices usage. Further investigation is needed to elucidate the potential impact of LCMs emission via WWTP effluent on the aquatic receiving ecosystem.
Collapse
Affiliation(s)
- Yuting Zhan
- School of Energy and Environment and State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong, China
| | - Qianqian Jin
- School of Energy and Environment and State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong, China; Research Centre for the Oceans and Human Health, City University of Hong Kong Shenzhen Research Institute, Shenzhen 518057, China
| | - Huiju Lin
- School of Energy and Environment and State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong, China
| | - Danyang Tao
- State Key Laboratory of Marine Pollution and Department of Chemistry, City University of Hong Kong, Hong Kong, China
| | - Lok Yung Law
- School of Energy and Environment and State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong, China
| | - Jiaji Sun
- School of Energy and Environment and State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong, China
| | - Yuhe He
- School of Energy and Environment and State Key Laboratory of Marine Pollution, City University of Hong Kong, Hong Kong, China; Research Centre for the Oceans and Human Health, City University of Hong Kong Shenzhen Research Institute, Shenzhen 518057, China.
| |
Collapse
|
21
|
Jacobson B, Li S, Marin Rivera R, Daly P, Elgar CE, Mulvihill DM, Abbott AP, Feeney A, Prentice P. A mechanistic study identifying improved technology critical metal delamination from printed circuit boards at lower power sonications in a deep eutectic solvent. ULTRASONICS SONOCHEMISTRY 2023; 101:106701. [PMID: 38029568 PMCID: PMC10711237 DOI: 10.1016/j.ultsonch.2023.106701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 11/06/2023] [Accepted: 11/17/2023] [Indexed: 12/01/2023]
Abstract
Deep eutectic solvents (DESs) are an emerging class of ionic liquids that offer a solution to reclaiming technology critical metals (TCMs) from electronic waste, with potential for improved life cycle analysis. The high viscosities typical of DESs, however, impose mass transport limitations such that passive TCM removal generally requires immersion over extended durations, in some cases in the order of hours. It is postulated that, through the targeted application of power ultrasound, delamination of key structures in electronic components immersed in DESs can be significantly accelerated, thereby enabling rapid recovery of TCMs. In this paper, we fully characterise cavitation in a Choline Chloride-Ethylene Glycol DES as a function of sonotrode input power, by the acoustic detection of the bubble collapse shockwave content generated during sonications at more than 20 input powers over the available range. This justifies the selection of two powers for a detailed study of ultrasonically enhanced TCM-delamination from printed circuit boards (PCBs). Dual-perspective high-speed imaging is employed, which facilitates simultaneous observation of TCM removal, and the cavitation evolution and interaction with the PCB surface. Bubble jetting is identified as a key contributor to initial pitting of the TCM layers, exposing the larger underlying copper layer, with the contributions of additional inertial cavitation-mediated phenomena such as bubble-collapse shockwaves also demonstrated as important for delamination. Optimal cavitation activity throughout the sonication then promotes etching of the copper base layer of the PCB structure targeted by the DES, liberating the overlaying TCMs in sections as large as 0.79 mm2. We report a thirtyfold improvement in processing time compared to passive delamination, with sonications at the lower power outperforming those at the higher power. The results demonstrate the potential for industrially scalable recovery of TCMs from the growing quantities of global e-waste, using combined power ultrasonics and DESs.
Collapse
Affiliation(s)
- Ben Jacobson
- James Watt School of Engineering, University of Glasgow, Glasgow G12 8QQ, UK.
| | - Shida Li
- James Watt School of Engineering, University of Glasgow, Glasgow G12 8QQ, UK
| | | | - Paul Daly
- James Watt School of Engineering, University of Glasgow, Glasgow G12 8QQ, UK
| | | | - Daniel M Mulvihill
- James Watt School of Engineering, University of Glasgow, Glasgow G12 8QQ, UK
| | - Andrew P Abbott
- School of Chemistry, University of Leicester, Leicester LE1 7RH, UK
| | - Andrew Feeney
- James Watt School of Engineering, University of Glasgow, Glasgow G12 8QQ, UK
| | - Paul Prentice
- James Watt School of Engineering, University of Glasgow, Glasgow G12 8QQ, UK
| |
Collapse
|
22
|
Elumalai S, Prabhu K, Selvan GP, Ramasamy P. Review on heavy metal contaminants in freshwater fish in South India: current situation and future perspective. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:119594-119611. [PMID: 37945961 DOI: 10.1007/s11356-023-30659-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Accepted: 10/20/2023] [Indexed: 11/12/2023]
Abstract
The primary natural resource we use in our daily lives for a variety of activities is freshwater for drinking and various developmental goals. Furthermore, the pace of human population increase worldwide is rising rapidly and has a great impact on the Earth's natural resources. Natural water quality has diminished owing to various anthropogenic activities. Water is crucial to the life cycle. On the other hand, chemical and agricultural industries pollute heavy metals. Acute and chronic diseases caused by heavy metals, such as slow metabolism and damage to the gills and epithelial layer of fish species, are divided into two categories. Pollutants can also harm liver tissues and result in ulceration as well as diseases such as fin rot, tail rot, and gill disease. The most prevalent heavy metals are As, Cr, Pb, and Hg, which are systemic toxicants that affect human health. These metals are categorized as carcinogens by the US Environmental Protection Agency and the worldwide agency for cancer research because they cause organ damage even at low exposure levels. The focus of the current study is to review various freshwater sources of heavy metal pollution.
Collapse
Affiliation(s)
- Saranya Elumalai
- Department of Biotechnology, Vinayaka Missions Kirupananda Variyar Engineering College, Salem, Tamil Nadu, 636308, India
| | - Kolandhasamy Prabhu
- Department of Marine Science, Bharathidasan University, Tiruchirappalli, Tamil Nadu, 620024, India
| | - Gopi Palani Selvan
- Department of Oceanography & Coastal Area Studies, Alagappa University, Thondi Campus, Thondi, Tamil Nadu, 623409, India
| | - Pasiyappazham Ramasamy
- Department of Physiology, Basic Medical Sciences, Saveetha Dental College & Hospitals, Saveetha Institute of Medical and Technical Sciences (SIMATS), Saveetha University, Chennai, Tamil Nadu, 600077, India.
| |
Collapse
|
23
|
Mishra S, Ghosh S, van Hullebusch ED, Singh S, Das AP. A Critical Review on the Recovery of Base and Critical Elements from Electronic Waste-Contaminated Streams Using Microbial Biotechnology. Appl Biochem Biotechnol 2023; 195:7859-7888. [PMID: 36988841 DOI: 10.1007/s12010-023-04440-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/15/2023] [Indexed: 03/30/2023]
Abstract
Pollution by end-of-life electronics is a rapid ever-increasing threat and is a universal concern with production of million metric tons of these wastes per annum. Electronic wastes (E-waste) are rejected electric or electronic equipment which have no other applications. The aggrandized unproper land filling of E-waste may generate hazardous effects on living organisms and ecosystem. At present, millions of tons of E-waste await the advancement of more efficient and worthwhile recycling techniques. Recovery of base and critical elements from electronic scraps will not only reduce the mining of these elements from natural resources but also reduces the contamination caused by the hazardous chemicals (mostly organic micropollutants) released from these wastes when unproperly disposed of. Bioleaching is reported to be the most eco-friendly process for metal recycling from spent electronic goods. A detailed investigation of microbial biodiversity and a molecular understanding of the metabolic pathways of bioleaching microorganisms will play a vital function in extraction of valuable minerals from the end-of-life scraps. Bioleaching technique as an economic and green technology costs around 7 USD per kg for effective reusing of E-waste as compared to other physical and chemical techniques. This review provides a summary of worldwide scenario of electronic pollutants; generation, composition and hazardous components of electronic waste; recycling of valuable elements through bioleaching; mechanism of bioleaching; microorganisms involved in base and critical element recovery from E-waste; commercial bioleaching operations; and upcoming aspects of this eco-friendly technique.
Collapse
Affiliation(s)
- Sunanda Mishra
- Department of Botany, College of Basic Science and Humanities, Odisha University of Agriculture and Technology, Bhubaneswar, 751003, Odisha, India
| | | | - Eric D van Hullebusch
- Université Paris Cité, Institut de Physique du Globe de Paris, CNRS, 75005, Paris, France
| | - Shikha Singh
- Department of Life Sciences, Rama Devi Women's University, 751022, Bhubaneswar, Odisha, India
| | - Alok Prasad Das
- Department of Life Sciences, Rama Devi Women's University, 751022, Bhubaneswar, Odisha, India.
| |
Collapse
|
24
|
Gómez Duran JA, Arroyo ZG, Gómez Castro FI, Owen PQ, Sánchez Cadena LE, Ayala Gómez MV. Evaluation of the effect of physical and chemical factors in the recovery of Cu, Pb and Fe from waste PCB through acid leaching. Heliyon 2023; 9:e21348. [PMID: 38027605 PMCID: PMC10651467 DOI: 10.1016/j.heliyon.2023.e21348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 10/07/2023] [Accepted: 10/19/2023] [Indexed: 12/01/2023] Open
Abstract
Electronic waste recycling is a strategy that contributes to implement a circular economy model which include reuse, component and raw material recovery and minimum final deposition. Given the importance of reincorporating the components of electronic devices into the productive chain and a correct recovery for some hazardous metals such as lead contained in such residues. This study is focused on the effect of maximum available content (MAC) of metal, sulfuric acid initial concentration, agitation velocity, and oxidising agent on the recovery of copper, lead and iron from electronic waste through acid leaching. A solid-state characterization before and after treatment and electrochemical analysis was carried out to analyse MCA effects and surface chemistry. It was found that sub-millimetric particles show a better available extraction percentage in case of copper and iron, being opposite for lead. Presence of hydrogen peroxide enhance the extraction efficiency, however, this cause iron and lead precipitation, therefore it is inefficient for metals recovery as well as for reagent consumption. The presence of calcium salts reacts producing gypsum, which reduces the extraction yield of copper at particle size below 250 μm.
Collapse
Affiliation(s)
- Jaime A. Gómez Duran
- Departamento de Ingeniería Química, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Noria Alta S/N, Guanajuato, Gto., 36050, Mexico
| | - Zeferino Gamiño Arroyo
- Departamento de Ingeniería Química, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Noria Alta S/N, Guanajuato, Gto., 36050, Mexico
| | - Fernando Israel Gómez Castro
- Departamento de Ingeniería Química, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Noria Alta S/N, Guanajuato, Gto., 36050, Mexico
| | - Patricia Quintana Owen
- Departamento de Física Aplicada, CINVESTAV-IPN, A.P. 73, Cordemex, 97310, Mérida, Yucatán, Mexico
| | - Lorena Eugenia Sánchez Cadena
- Departamento de Ingeniería Civil, Campus Guanajuato, Universidad de Guanajuato, Calle Juárez 77, Col. Centro, Guanajuato, Gto, C.P, 36000 , Mexico
| | - Mónica V. Ayala Gómez
- Departamento de Química, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Noria Alta S/N, Guanajuato, Gto, 36050, Mexico
| |
Collapse
|
25
|
Kepper M, Karim MN, Baune M, Thöming J, Pesch GR. Influence of the filter grain morphology on separation efficiency in dielectrophoretic filtration. Electrophoresis 2023; 44:1645-1654. [PMID: 37380622 DOI: 10.1002/elps.202300075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 06/09/2023] [Accepted: 06/20/2023] [Indexed: 06/30/2023]
Abstract
Recovery of noble materials from waste is essential for industries around the globe. Dielectrophoretic (DEP) filtration, an electrically switchable particle separation technique, can be applied to tackle this challenge. It is highly selective regarding particle size, material or shape. Expanding the scope of DEP towards high throughput and improving the trapping efficiency are vital to make DEP a viable robust alternative to conventional separation methods. DEP filtration works by selective immobilisation of particles in a porous medium by the action of an inhomogeneous electric field. The field inhomogeneity comes from scattering an electric field at the phase boundary between the particle suspension and the filter surface. In this article, we show how the filter structure affects the DEP separation. We study fixed bed filters of three different grain types and find that the morphology of the grains highly influences the DEP filter efficiency. Specifically, grains with irregular surface structure and high perceived angularity show high separation efficiency. We believe these insights into the design of DEP filtration will pave the way towards its application in, for example, the recovery of valuable materials from electronic waste dust.
Collapse
Affiliation(s)
- Mariia Kepper
- Faculty of Production Engineering, Chemical Process Engineering (CVT), University of Bremen, Bremen, Germany
| | - Md Nurul Karim
- Faculty of Production Engineering, Advanced Ceramics, University of Bremen, Bremen, Germany
| | - Michael Baune
- Faculty of Production Engineering, Chemical Process Engineering (CVT), University of Bremen, Bremen, Germany
| | - Jorg Thöming
- Faculty of Production Engineering, Chemical Process Engineering (CVT), University of Bremen, Bremen, Germany
- MAPEX Center for Materials and Processes, University of Bremen, Bremen, Germany
| | - Georg R Pesch
- Faculty of Production Engineering, Chemical Process Engineering (CVT), University of Bremen, Bremen, Germany
- School of Chemical and Bioprocess Engineering, University College Dublin, Dublin, Ireland
| |
Collapse
|
26
|
Vlasopoulos D, Mendrinou P, Oustadakis P, Kousi P, Stergiou A, Karamoutsos SD, Hatzikioseyian A, Tsakiridis PE, Remoundaki E, Agatzini-Leonardou S. Hydrometallurgical recovery of silver and gold from waste printed circuit boards and treatment of the wastewater in a biofilm reactor: An integrated pilot application. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 344:118334. [PMID: 37354591 DOI: 10.1016/j.jenvman.2023.118334] [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: 01/31/2023] [Revised: 06/01/2023] [Accepted: 06/04/2023] [Indexed: 06/26/2023]
Abstract
A hydrometallurgical process for the recovery of gold and silver from waste printed circuit boards (PCBs) was experimentally verified and tested at pilot scale. The process comprises four sequential leaching stages; the first two based on HCl, correspond to base metals (e.g. Sn, Cu) removal, while the third is based on HNO3 for Ag leaching and the final on aqua regia for Au leaching. After base metals leaching, the solid residue, enriched in silver and gold about 5 times, contained silver almost quantitively as insoluble AgCl and significant losses (Ag loss <8%) were avoided. The necessary reduction of Ag in the solid phase was achieved with a solution of 0.5 M N2H4 and 3 M NaOH, at 80 °C and S/L ratio 10%. Leaching of silver by 4 M HNO3 was followed by its recovery from nitrate solution by 0.08 Μ N2H4 at ambient temperature with an efficiency of 83%. Gold was leached by aqua regia and quantitively recovered by 0.13 M N2H4 at ambient temperature. Wastewater resulting from the process, rich in nitrate (5 g/L) and chloride (50 g/L), was treated by an effective and novel biological denitrification system tolerating metals at ppm level, to comply with zero nitrate and residual metals discharge guidelines. The overall process requires low reagents and energy input and has zero discharge for liquid effluents. The scheme is appropriate to be applied at local small to medium industrial units, complying with decentralized circular economy principles for metal recovery from electronic waste.
Collapse
Affiliation(s)
- Dimitrios Vlasopoulos
- School of Mining and Metallurgical Engineering, National Technical University of Athens (NTUA), Heroon Polytechniou 9, 15780, Zografou, Greece
| | - Panagiota Mendrinou
- School of Mining and Metallurgical Engineering, National Technical University of Athens (NTUA), Heroon Polytechniou 9, 15780, Zografou, Greece
| | - Paschalis Oustadakis
- School of Mining and Metallurgical Engineering, National Technical University of Athens (NTUA), Heroon Polytechniou 9, 15780, Zografou, Greece
| | - Pavlina Kousi
- School of Mining and Metallurgical Engineering, National Technical University of Athens (NTUA), Heroon Polytechniou 9, 15780, Zografou, Greece
| | | | | | - Artin Hatzikioseyian
- School of Mining and Metallurgical Engineering, National Technical University of Athens (NTUA), Heroon Polytechniou 9, 15780, Zografou, Greece
| | - Petros E Tsakiridis
- School of Mining and Metallurgical Engineering, National Technical University of Athens (NTUA), Heroon Polytechniou 9, 15780, Zografou, Greece
| | - Emmanouella Remoundaki
- School of Mining and Metallurgical Engineering, National Technical University of Athens (NTUA), Heroon Polytechniou 9, 15780, Zografou, Greece.
| | - Styliani Agatzini-Leonardou
- School of Mining and Metallurgical Engineering, National Technical University of Athens (NTUA), Heroon Polytechniou 9, 15780, Zografou, Greece
| |
Collapse
|
27
|
Hernández-Fernández A, Iniesta-López E, Ginestá-Anzola A, Garrido Y, Pérez de los Ríos A, Quesada-Medina J, Hernández-Fernández FJ. Polymeric Inclusion Membranes Based on Ionic Liquids for Selective Separation of Metal Ions. MEMBRANES 2023; 13:795. [PMID: 37755217 PMCID: PMC10535514 DOI: 10.3390/membranes13090795] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 09/12/2023] [Accepted: 09/12/2023] [Indexed: 09/28/2023]
Abstract
In this work, poly(vinyl chloride)-based polymeric ionic liquid inclusion membranes were used in the selective separation of Fe(III), Zn(II), Cd(II), and Cu(II) from hydrochloride aqueous solutions. The ionic liquids under study were 1-octyl-3-methylimidazolium hexafluorophosphate, [omim+][PF6-] and methyl trioctyl ammonium chloride, [MTOA+][Cl-]. For this purpose, stability studies of different IL/base polymer compositions against aqueous phases were carried out. Among all polymer inclusion membranes studied, [omim+][PF6-]/PVC membranes at a ratio of 30/70 and [MTOA+][Cl-]/PVC membranes at a ratio of 70/30 were able to retain up to 82% and 48% of the weight of the initial ionic liquid, respectively, after being exposed to a solution of metal ions in 1 M HCl for 2048 h (85 days). It was found that polymer inclusion membranes based on the ionic liquid methyl trioctyl ammonium chloride allowed the selective separation of Zn(II)/Cu(II) and Zn(II)/Fe(III) mixtures with separation factors of 1996, 606 and, to a lesser extent but also satisfactorily, Cd(II)/Cu(II) mixtures, with a separation factor of 112. Therefore, selecting the appropriate ionic liquid/base polymer mixture makes it possible to create polymeric inclusion membranes capable of selectively separating target metal ions.
Collapse
Affiliation(s)
- Adrián Hernández-Fernández
- Department of Chemical Engineering, Faculty of Chemistry, University of Murcia (UMU), P.O. Box 4021, Campus de Espinardo, E-30100 Murcia, Spain; (A.H.-F.); (E.I.-L.); (Y.G.); (A.P.d.l.R.); (J.Q.-M.)
| | - Eduardo Iniesta-López
- Department of Chemical Engineering, Faculty of Chemistry, University of Murcia (UMU), P.O. Box 4021, Campus de Espinardo, E-30100 Murcia, Spain; (A.H.-F.); (E.I.-L.); (Y.G.); (A.P.d.l.R.); (J.Q.-M.)
| | | | - Yolanda Garrido
- Department of Chemical Engineering, Faculty of Chemistry, University of Murcia (UMU), P.O. Box 4021, Campus de Espinardo, E-30100 Murcia, Spain; (A.H.-F.); (E.I.-L.); (Y.G.); (A.P.d.l.R.); (J.Q.-M.)
| | - Antonia Pérez de los Ríos
- Department of Chemical Engineering, Faculty of Chemistry, University of Murcia (UMU), P.O. Box 4021, Campus de Espinardo, E-30100 Murcia, Spain; (A.H.-F.); (E.I.-L.); (Y.G.); (A.P.d.l.R.); (J.Q.-M.)
| | - Joaquín Quesada-Medina
- Department of Chemical Engineering, Faculty of Chemistry, University of Murcia (UMU), P.O. Box 4021, Campus de Espinardo, E-30100 Murcia, Spain; (A.H.-F.); (E.I.-L.); (Y.G.); (A.P.d.l.R.); (J.Q.-M.)
| | - Francisco José Hernández-Fernández
- Department of Chemical Engineering, Faculty of Chemistry, University of Murcia (UMU), P.O. Box 4021, Campus de Espinardo, E-30100 Murcia, Spain; (A.H.-F.); (E.I.-L.); (Y.G.); (A.P.d.l.R.); (J.Q.-M.)
| |
Collapse
|
28
|
Qiao Z, Luo K, Zhou S, Fu M, Shao X, Gong K, Peng C, Zhang W. Response mechanism of lettuce (Lactuca sativa L.) under combined stress of Cd and DBDPE: An integrated physiological and metabolomics analysis. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 887:164204. [PMID: 37196961 DOI: 10.1016/j.scitotenv.2023.164204] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 05/11/2023] [Accepted: 05/12/2023] [Indexed: 05/19/2023]
Abstract
DBDPE and Cd are representative contaminants commonly found in electronic waste (e-waste), which tend to be gradually discharged and accumulated in the environment during e-waste dismantling, resulting in frequent outbreaks and detection of these pollutants. The toxicity of both chemicals to vegetables after combined exposure has not been determined. The accumulation and mechanisms of phytotoxicity of the two compounds, alone and in combination, were studied using lettuce. The results showed that the enrichment ability of Cd and DBDPE in root was significantly higher than that in aerial part. Exposure to 1 mg/L Cd + DBDPE reduced the toxicity of Cd to lettuce, while exposure to 5 mg/L Cd + DBDPE increased the toxicity of Cd to lettuce. The absorption of Cd in the underground part of lettuce of 5 mg/L Cd + DBDPE was significantly increased by 108.75 % compared to 5 mg/L Cd. The significant enhancement of antioxidant system activity in lettuce under 5 mg/L Cd + DBDPE exposure, and the root activity and total chlorophyll content were decreased by 19.62 % and 33.13 %, respectively, compared to the control. At the same time, the organelles and cell membranes of lettuce root and leaf were significantly damaged, which was significantly worse than that of single Cd and DBDPE treatment. Combined exposure significantly affected the pathways related to amino acid metabolism, carbon metabolism and ABC transport in lettuce. This study filled the safety gap of DBDPE and Cd combined exposure on vegetables and would provide a theoretical basis for the environmental behavior and toxicological study of DBDPE and Cd.
Collapse
Affiliation(s)
- Zhihua Qiao
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, School of Resource and Environmental Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Kailun Luo
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, School of Resource and Environmental Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Shanqi Zhou
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, School of Resource and Environmental Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Mengru Fu
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, School of Resource and Environmental Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Xuechun Shao
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, School of Resource and Environmental Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Kailin Gong
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, School of Resource and Environmental Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Cheng Peng
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, School of Resource and Environmental Engineering, East China University of Science and Technology, Shanghai 200237, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Wei Zhang
- State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, School of Resource and Environmental Engineering, East China University of Science and Technology, Shanghai 200237, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China.
| |
Collapse
|
29
|
Wang Y, Xu J, Liu G. Characteristics and health risk assessment of heavy metals in dust of a waste printed circuit board recycling workshop, China. RSC Adv 2023; 13:22216-22225. [PMID: 37492512 PMCID: PMC10363715 DOI: 10.1039/d3ra03164k] [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: 05/12/2023] [Accepted: 06/17/2023] [Indexed: 07/27/2023] Open
Abstract
Physical separation is the most widely used technology concerning waste printed circuit board (WPCB) recycling in practical terms. The dust generated from the process poses a significant environmental and human health risk. Amounts of heavy metals in dust present in each processing zone of the workshop showed differences. However, to date, few studies have reported this. The mean metal concentrations in workshop dust from different processing zones were investigated in this study and it was found that Zn, Pb, and Sn appeared in higher levels than other metals, followed by Mn > Cr > Ni > V > As > Cd. The enrichment factors (EFs) ranged from 1.15 to 207.4, and decreased in the order of Cu > Sn > Pb > Zn > Cd > Cr > Ni > V > As, which was exactly consistent with the geo-accumulation index values. The comparison of the EF values of workshop dust in and outside showed that the EFs in workshop dust were mostly smaller. Metals in the dust of the crushing zone (CrZ) showed significant and strong enrichment. The non-carcinogenic risk for different processing zones was all less than 1, which is recognized safety for people's health. The total carcinogenic risk from Cr, and Ni in all zones and As in the CrZ exposure was not negligible. The carcinogenic and non-carcinogenic risks in the CrZ were significantly higher than in the other zones. Masks to filter dust, a ventilation system, daily work hours reduction, and automation improvement was proposed for reducing workers' exposure to heavy metal.
Collapse
Affiliation(s)
- Ye Wang
- CAS Key Laboratory of Crust-Mantle Materials and Environment, School of Earth and Space Sciences, University of Science and Technology of China Hefei Anhui 230026 China +86-551-63621485 +86-551-63603714
- Solid Waste Management Center of Anhui Province Hefei Anhui 230061 China
| | - Jingru Xu
- CAS Key Laboratory of Crust-Mantle Materials and Environment, School of Earth and Space Sciences, University of Science and Technology of China Hefei Anhui 230026 China +86-551-63621485 +86-551-63603714
| | - Guijian Liu
- CAS Key Laboratory of Crust-Mantle Materials and Environment, School of Earth and Space Sciences, University of Science and Technology of China Hefei Anhui 230026 China +86-551-63621485 +86-551-63603714
| |
Collapse
|
30
|
Tushar Q, Salehi S, Santos J, Zhang G, Bhuiyan MA, Arashpour M, Giustozzi F. Application of recycled crushed glass in road pavements and pipeline bedding: An integrated environmental evaluation using LCA. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 881:163488. [PMID: 37068664 DOI: 10.1016/j.scitotenv.2023.163488] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2023] [Revised: 04/07/2023] [Accepted: 04/09/2023] [Indexed: 06/01/2023]
Abstract
The study aims to conduct a comprehensive life cycle assessment (LCA) of mixed glass waste (MGW) recycling processes to quantify the environmental impacts of crushed glass as a partial substitute for virgin aggregate. Upstream washing, crushing, and sorting conducted at material recycling facilities (MRF) are the prime activities to assess whether reprocessed MGW in pavement construction is an alternate feasible solution. None of the previous studies explicitly account for the relative uncertainties and optimization of waste glass upstream processes from an environmental perspective. The study calculates environmental impacts using the LCA tool SimaPro considering design factors attributed to transportation, electricity consumption, use of chemicals, and water for reprocessing glass waste. Relative uncertainties of design variables and the national transition policy (2021-2030) from non-renewable to renewable energy sources have been validated by performing detailed Monte Carlo simulations. The correlation coefficients (r = 0.64, 0.58, and 0.49) of successive variables explain how the higher environmental gains of the glass recycling process are outweighed by diesel, energy consumption, and transportation distances. Compared to natural quarry sand, the recycled glass aggregate produced through crushing and recycling of its by-products reduces CO2eq emissions by 16.2 % and 46.7 %, respectively. The need for a washing line at the plant, in addition to crushing, results in a higher environmental impact over natural sand by 90.1 % and emphasizes the benefits of collecting waste glass through a separate bin, hence avoiding contamination. The result indicates that the benefit of lowering emissions varies significantly when considering waste glass landfilling. Moreover, this study evaluates the potential impacts on asphalt and reinforced concrete pavements (RCP) with 5 %, 10 %, 15 %, and 20 % replacement of natural sand with recycled glass aggregate. The LCA emphasizes the limitations of energy-intensive waste glass reprocessing. The obtained results and uncertainty analysis based on primary MRF data and recycled product applications provide meaningful suggestions for a more fit-for-purpose waste management and natural resource conservation.
Collapse
Affiliation(s)
- Quddus Tushar
- Civil and Infrastructure Engineering, RMIT University, GPO Box 2476, Melbourne, VIC 3001, Australia
| | - Safoura Salehi
- Department of Civil Engineering, Monash University, Melbourne, VIC 3800, Australia
| | - Joao Santos
- Department of Construction Management and Engineering, University of Twente, Enschede, the Netherlands
| | - Guomin Zhang
- Civil and Infrastructure Engineering, RMIT University, GPO Box 2476, Melbourne, VIC 3001, Australia
| | - Muhammed A Bhuiyan
- Civil and Infrastructure Engineering, RMIT University, GPO Box 2476, Melbourne, VIC 3001, Australia
| | - Mehrdad Arashpour
- Department of Civil Engineering, Monash University, Melbourne, VIC 3800, Australia
| | - Filippo Giustozzi
- Civil and Infrastructure Engineering, RMIT University, GPO Box 2476, Melbourne, VIC 3001, Australia.
| |
Collapse
|
31
|
Andeobu L, Wibowo S, Grandhi S. Informal E-waste recycling practices and environmental pollution in Africa: What is the way forward? Int J Hyg Environ Health 2023; 252:114192. [PMID: 37348165 DOI: 10.1016/j.ijheh.2023.114192] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 05/21/2023] [Accepted: 05/22/2023] [Indexed: 06/24/2023]
Abstract
Globally, e-waste is the fastest growing and most valuable waste-stream. While countries worldwide are increasingly acknowledging the e-waste problem and introducing policies and regulations that deal with e-waste, large quantities of e-waste still go undocumented. Much of these global e-wastes are accumulating in open-dumpsites and landfills in African-countries where they are recycled informally resulting in significant environmental and public-health concerns. Although, there is a plethora of studies on e-waste management and disposal, only a few-studies have focused on African-countries who are major recipients of e-waste. Moreover, despite the attempts to mitigate the problem of e-waste in African-countries, e-waste has remained a major-concern and there are currently very limited workable solutions. This study examines informal e-waste recycling, environmental pollution and the extent of environmental and health impacts in major countries of concern including Ghana, Nigeria, Egypt, Kenya and South Africa. The global e-waste Waste Atlas Report, 2020 identified these countries as major recipients of e-waste. To achieve the aims of this research, previous studies from 2005 to 2022 are collected from various databases and analyzed. Accordingly, this study focuses on environmental pollution and public-health impacts resulting from e-waste dumping and informal recycling practices, illegal transboundary shipment of e-waste to the selected countries, and the interventions of governments and international organizations in reducing the impact of e-waste pollution and informal recycling practices in Africa. Based on the outcomes of this study, practical approaches on the way-forward are recommended. The findings of this study contribute to a growing-body of research on informal e-waste recycling practices in Africa to document that individuals working within e-waste sites and residents in nearby communities are exposed to a number of toxic-substances, some at potentially concerning levels.
Collapse
Affiliation(s)
- Lynda Andeobu
- Central Queensland University, 120 Spencer Street, Melbourne 3000, Australia.
| | - Santoso Wibowo
- Central Queensland University, 120 Spencer Street, Melbourne 3000, Australia.
| | | |
Collapse
|
32
|
Wang B, Ma Y, Xu W, Tang K. A novel S,N-rich MOF for efficient recovery of Au(III): Performance and mechanism. JOURNAL OF HAZARDOUS MATERIALS 2023; 451:131051. [PMID: 36933505 DOI: 10.1016/j.jhazmat.2023.131051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 02/17/2023] [Accepted: 02/19/2023] [Indexed: 06/18/2023]
Abstract
A novel S,N-rich MOF with adenine and 4,4'-thiodiphenol as organic ligands was synthesized via the one-step solvothermal method, and used for gold recovery. The pH impact, adsorption kinetics, isotherms, thermodynamics, selectivity, and reusability were investigated accordingly. The adsorption and desorption mechanism were also explored comprehensively. The electronic attraction, coordination, and in situ redox account for the Au(III) adsorption. The Au(III) adsorption is affected strongly by the pH of solutions, and best at pH of 2.57. The MOF exhibits exceptional adsorption capacity as high as 3680 mg/g at 55 °C, fast kinetics with 8 min for 9.6 mg/L Au(III), and excellent selectivity for gold ion in real e-waste leachates. The adsorption process of gold on the adsorbent is endothermic and spontaneous, and influenced visibly by temperature. The adsorption ratio still maintained 99% after seven adsorption-desorption cycles. The column adsorption experiments show that the MOF has outstanding selectivity for Au(III) with 100% of removal efficiency in a complex solution containing Au, Ni, Cu, Cd, Co, and Zn ions. A glorious adsorption with a breakthrough time of 532 mins was obtained for the breakthrough curve. This study not only provides an efficient adsorbent for gold recovery, but also guidance for designing new materials.
Collapse
Affiliation(s)
- Baihui Wang
- Department of Chemistry and Chemical Engineering, Hunan Institute of Science and Technology, Yueyang 414006, Hunan, China
| | - Yingnan Ma
- Department of Chemistry and Chemical Engineering, Hunan Institute of Science and Technology, Yueyang 414006, Hunan, China
| | - Weifeng Xu
- Department of Chemistry and Chemical Engineering, Hunan Institute of Science and Technology, Yueyang 414006, Hunan, China.
| | - Kewen Tang
- Department of Chemistry and Chemical Engineering, Hunan Institute of Science and Technology, Yueyang 414006, Hunan, China.
| |
Collapse
|
33
|
Bernardo M, Lapa N, Pinto F, Nogueira M, Matos I, Ventura M, Ferraria AM, do Rego AMB, Fonseca IM. Valorisation of spent tire rubber as carbon adsorbents for Pb(II) and W(VI) in the framework of a Circular Economy. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:74820-74837. [PMID: 37209332 PMCID: PMC10293437 DOI: 10.1007/s11356-023-27689-5] [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: 01/24/2023] [Accepted: 05/12/2023] [Indexed: 05/22/2023]
Abstract
Spent tire rubber-derived chars and their corresponding H3PO4 and CO2-activated chars were used as adsorbents in the recovery of Pb(II) ion and (W(VI)) oxyanion from synthetic solutions. The developed chars (both raw and activated) were thoroughly characterized to have insight about their textural and surface chemistry properties. H3PO4-activated chars presented lower surface areas than the raw chars and an acidic surface chemistry which affected the performance of these samples as they showed the lowest removals of the metallic ions. On the other hand, CO2-activated chars presented increased surface areas and increased mineral content compared to the raw chars, having presented higher uptake capacities for both Pb(II) (103-116 mg/g) and W(VI) (27-31 mg/g) ions. Cation exchange with Ca, Mg and Zn ions was appointed as a mechanism for Pb removal, as well as surface precipitation in the form of hydrocerussite (Pb3(CO3)2(OH)2). W(VI) adsorption might have been ruled by strong electrostatic attractions between the negatively charged tungstate species and the highly positively charged carbons' surface.The results shown in this work allow concluding that the valorisation of spent tire rubber through pyrolysis and the subsequent activation of the obtained chars is an alternative and a feasible option to generate adsorbent materials with a high uptake capacity of critical metallic elements.
Collapse
Affiliation(s)
- Maria Bernardo
- LAQV/REQUIMTE, Departamento de Química, Faculdade de Ciências E Tecnologia, Universidade Nova de Lisboa, 2829-516, Caparica, Portugal.
| | - Nuno Lapa
- LAQV/REQUIMTE, Departamento de Química, Faculdade de Ciências E Tecnologia, Universidade Nova de Lisboa, 2829-516, Caparica, Portugal
| | - Filomena Pinto
- Laboratório Nacional de Energia E Geologia (LNEG), Unidade de Bioenergia (UB), Estrada Do Paço Do Lumiar, Ed. J, 1649-038, Lisbon, Portugal
| | - Miguel Nogueira
- LAQV/REQUIMTE, Departamento de Química, Faculdade de Ciências E Tecnologia, Universidade Nova de Lisboa, 2829-516, Caparica, Portugal
| | - Inês Matos
- LAQV/REQUIMTE, Departamento de Química, Faculdade de Ciências E Tecnologia, Universidade Nova de Lisboa, 2829-516, Caparica, Portugal
| | - Márcia Ventura
- LAQV/REQUIMTE, Departamento de Química, Faculdade de Ciências E Tecnologia, Universidade Nova de Lisboa, 2829-516, Caparica, Portugal
| | - Ana Maria Ferraria
- Departamento de Engenharia Química, BSIRG, IBB - Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, 1049-001, Lisbon, Portugal
- Associate Laboratory i4HB-Institute for Health and Bioeconomy at Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001, Lisbon, Portugal
| | - Ana Maria Botelho do Rego
- Departamento de Engenharia Química, BSIRG, IBB - Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de Lisboa, 1049-001, Lisbon, Portugal
- Associate Laboratory i4HB-Institute for Health and Bioeconomy at Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001, Lisbon, Portugal
| | - Isabel Maria Fonseca
- LAQV/REQUIMTE, Departamento de Química, Faculdade de Ciências E Tecnologia, Universidade Nova de Lisboa, 2829-516, Caparica, Portugal
| |
Collapse
|
34
|
Gautam P, De AK, Sinha I, Behera CK, Singh KK. Genesis of copper oxide nanoparticles from waste printed circuit boards and evaluation of their photocatalytic activity. ENVIRONMENTAL RESEARCH 2023; 229:115951. [PMID: 37084944 DOI: 10.1016/j.envres.2023.115951] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 03/09/2023] [Accepted: 04/18/2023] [Indexed: 05/03/2023]
Abstract
Discarded Printed Circuit Boards (PCBs) are one of the secondary resources of high-purity copper, and precious materials, which if disposed off inappropriately may present several environmental risks. This study focuses on the production of copper oxide nanoparticles (CuO NPs) from reclaimed copper via a facile precipitation route to obtain a value-added nanoproduct. The synthesis involved the dissolution of downsized PCBs, leaching of Cu into the solution phase and the precipitation of nanoparticles (NPs) in an alkaline medium. XRD analysis confirmed the as-synthesized NPs were monoclinic CuO of size 19.23 nm without any impurity. HRTEM analysis confirmed that the NPs were nearly round spheres with average particle size of 19.973 ± 6.036 nm. The NPs have a specific surface area of 200 m2/g and mesoporous structure with mean pore diameter of 18.051 nm. The CuO NPs photocatalyzed the degradation of Congo Red under visible light irradiation. Hence, the PCB e-waste was utilized to produce nanomaterials with added-values, decreasing environmental problems.
Collapse
Affiliation(s)
- Pushpa Gautam
- Department of Metallurgical Engineering, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India.
| | - Arup Kumar De
- Department of Metallurgical Engineering, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India
| | - Indrajit Sinha
- Department of Chemistry, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India
| | - Chhail Kumar Behera
- Department of Metallurgical Engineering, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India
| | - Kamalesh Kumar Singh
- Department of Metallurgical Engineering, Indian Institute of Technology (Banaras Hindu University), Varanasi, 221005, India
| |
Collapse
|
35
|
Zhang S, Cheng Z, Yang M, Guo Z, Zhao L, Baqar M, Lu Y, Wang L, Sun H. Percutaneous Penetration of Liquid Crystal Monomers (LCMs) by In Vitro Three-Dimensional Human Skin Equivalents: Possible Mechanisms and Implications for Human Dermal Exposure Risks. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:4454-4463. [PMID: 36867107 DOI: 10.1021/acs.est.2c07844] [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] [Indexed: 06/18/2023]
Abstract
Liquid crystal monomers (LCMs) are indispensable materials in liquid crystal displays, which have been recognized as emerging persistent, bioaccumulative, and toxic organic pollutants. Occupational and nonoccupational exposure risk assessment suggested that dermal exposure is the primary exposure route for LCMs. However, the bioavailability and possible mechanisms of dermal exposure to LCMs via skin absorption and penetration remain unclear. Herein, we used EpiKutis 3D-Human Skin Equivalents (3D-HSE) to quantitatively assess the percutaneous penetration of nine LCMs, which were detected in e-waste dismantling workers' hand wipes with high detection frequencies. LCMs with higher log Kow and greater molecular weight (MW) were more difficult to penetrate through the skin. Molecular docking results showed that ABCG2 (an efflux transporter) may be responsible for percutaneous penetration of LCMs. These results suggest that passive diffusion and active efflux transport may be involved in the penetration of LCMs across the skin barrier. Furthermore, the occupational dermal exposure risks evaluated based on the dermal absorption factor suggested the underestimation of the continuous LCMs' health risks via dermal previously.
Collapse
Affiliation(s)
- Shaohan Zhang
- MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
| | - Zhipeng Cheng
- MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
| | - Ming Yang
- MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
| | - Zijin Guo
- MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
| | - Leicheng Zhao
- MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
| | - Mujtaba Baqar
- MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
| | - Yuan Lu
- MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
| | - Lei Wang
- MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
| | - Hongwen Sun
- MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
| |
Collapse
|
36
|
Su Z, Hou W, Wang J, Zhang Y, Jiang T. One-step separation of tin from e-waste by a chemical vapor transport process (CVT): Preparation of nano-SnO 2. WASTE MANAGEMENT (NEW YORK, N.Y.) 2023; 157:330-338. [PMID: 36603447 DOI: 10.1016/j.wasman.2022.12.037] [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: 08/01/2022] [Revised: 12/19/2022] [Accepted: 12/29/2022] [Indexed: 06/17/2023]
Abstract
E-waste is a valuable resource for the recovery of secondary metals. However, traditional methods only focused on the extraction of Cu and noble metals (Au, Ag, etc.), and significant tin (Sn) loss occurred during the smelting or the leached. In this paper, a novel chemical vapor transport (CVT) process was proposed to separate and recycle Sn from e-waste to prepare nano-SnO2. The effect of roasting parameters on Sn volatilization and characterization of nano-SnO2 were investigated using thermodynamic analysis, XRD, SEM, TEM, etc. The results indicated that Sn volatilization of 92.8 % was obtained under optimal roasting parameters under CO-CO2-N2 atmosphere. In addition, nano-SnO2 with a crystallinity of 99.9 %, an average grain size of 24.8 nm and a specific surface area of 97.9 m2/g was synthesized successfully.
Collapse
Affiliation(s)
- Zijian Su
- School of Minerals Processing and Bioengineering, Central South University, Changsha, China
| | - Wei Hou
- School of Minerals Processing and Bioengineering, Central South University, Changsha, China
| | - Jia Wang
- School of Minerals Processing and Bioengineering, Central South University, Changsha, China
| | - Yuanbo Zhang
- School of Minerals Processing and Bioengineering, Central South University, Changsha, China.
| | - Tao Jiang
- School of Minerals Processing and Bioengineering, Central South University, Changsha, China
| |
Collapse
|
37
|
Dutta D, Rautela R, Gujjala LKS, Kundu D, Sharma P, Tembhare M, Kumar S. A review on recovery processes of metals from E-waste: A green perspective. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 859:160391. [PMID: 36423849 DOI: 10.1016/j.scitotenv.2022.160391] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 11/06/2022] [Accepted: 11/17/2022] [Indexed: 06/16/2023]
Abstract
E-waste management has become a global concern because of the enormous rise in the rate of end-of-life electrical and electronic equipment's (EEEs). Disposal of waste EEE directly into the environment leads to adverse effects on the environment as well as on human health. For the management of E-waste, numerous studies have been carried out for extracting metals (base, precious, and rare earth) following pyrometallurgy, hydrometallurgy, and biometallurgy. Irrespective of the advantages of these processes, certain limitations still exist with each of these options in terms of their adoption as treatment techniques. Several journal publications regarding the different processes have been made which aids in future research in the field of E-waste management. This review provides a comprehensive summary of the various metal recovery processes (pyrometallurgy, hydrometallurgy, and biometallurgy) from E-waste, along with their advantages and limitations. A bibliometric study based on the published articles using different keywords in Scopus has been provided for a complete idea about E-waste with green technology perspective like bioleaching, biosorption, etc. The present study also focussed on the circular economic approach towards sustainable E-waste management along with its socio-economic aspects and the economic growth of the country. The present study would provide valuable knowledge in understanding E-waste and its different treatment processes to the students, researchers, industrialists, and policymakers of the country.
Collapse
Affiliation(s)
- Deblina Dutta
- Department of Environmental Science, SRM University- AP, Amaravati, Andhra Pradesh 522 240
| | - Rahul Rautela
- CSIR-National Environmental Engineering Research Institute (CSIR-NEERI), Nehru Marg, Nagpur 440 020, Maharashtra, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201 002, Uttar Pradesh, India
| | - Lohit Kumar Srinivas Gujjala
- CSIR-National Environmental Engineering Research Institute (CSIR-NEERI), Nehru Marg, Nagpur 440 020, Maharashtra, India
| | - Debajyoti Kundu
- CSIR-National Environmental Engineering Research Institute (CSIR-NEERI), Nehru Marg, Nagpur 440 020, Maharashtra, India
| | - Pooja Sharma
- CSIR-National Environmental Engineering Research Institute (CSIR-NEERI), Nehru Marg, Nagpur 440 020, Maharashtra, India
| | - Mamta Tembhare
- CSIR-National Environmental Engineering Research Institute (CSIR-NEERI), Nehru Marg, Nagpur 440 020, Maharashtra, India
| | - Sunil Kumar
- CSIR-National Environmental Engineering Research Institute (CSIR-NEERI), Nehru Marg, Nagpur 440 020, Maharashtra, India.
| |
Collapse
|
38
|
Ge X, Gao Y, Yang Y, Chen G, Ma S, Hu B, Yu Y, An T. Mixed bromine/chlorine transformation products of tetrabromobisphenol A formed in the combustion of printed circuit boards: Emission characteristics and transformation pathways. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 859:160104. [PMID: 36372166 DOI: 10.1016/j.scitotenv.2022.160104] [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: 10/17/2022] [Revised: 11/06/2022] [Accepted: 11/06/2022] [Indexed: 06/16/2023]
Abstract
Recently, mixed bromine/chlorine transformation products of tetrabromobisphenol A (ClyBrxBPAs) were found to be possibly related to the thermal treatment processes of electronic wastes. To explore their emission characteristics and formation mechanism, printed circuit board scraps were combusted in a tube furnace, under the temperature from 25 °C to 600 °C. The emission factor of the debromination products of tetrabromobisphenol A (BrxBPAs) was the highest, whereas that of ClyBrxBPAs was the lowest. Among three phases, most of the target compounds were partitioned into the oil and particle phases, and only negligible gaseous 2-BrBPA and bisphenol A were detected. The emission rates of most compounds were fastest at 300 °C, although 2-BrBPA, 2,6-Br2BPA, and 2-Cl-6-BrBPA peaked at 350 °C. Among the chemicals in total emission, 2-BrBPA was the dominant congener in BrxBPAs, whereas 2-Cl-2',6,6'-Br3BPA, 2-Cl-2',6#-Br2BPA, and Σ2Cl1Br1BPAs shared similar proportions in ClyBrxBPAs. Meanwhile, the composition profiles at 300 °C showed that 2,2',6-Br3BPA and 2-Cl-2',6,6'-Br3BPA occupied the largest proportions in BrxBPAs and ClyBrxBPAs, respectively. To reveal the possible transformation pathways, the Gibbs free energy was calculated based on a radical substitution reaction. After "•Br" removal from tetrabromobisphenol A or other BrxBPAs, the intermediate was more easily combined with "•H" than with "•Cl." In addition, the ClyBrxBPA formation via "-•H + •Cl" by BrxBPAs is nonspontaneous, thus limiting the further generation of ClyBrxBPAs. This study not only provides ideas for the study of other mixed halogenated products, but also provides constructive suggestions for environmental source analysis by combining previous research on the occurrence of ClyBrxBPAs in various environmental matrices.
Collapse
Affiliation(s)
- Xiang Ge
- Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, PR China; Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control, Key Laboratory of City Cluster Environmental Safety and Green Development, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, PR China
| | - Yanpeng Gao
- Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, PR China; Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control, Key Laboratory of City Cluster Environmental Safety and Green Development, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, PR China
| | - Yan Yang
- Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, PR China; Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control, Key Laboratory of City Cluster Environmental Safety and Green Development, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, PR China.
| | - Guanhui Chen
- Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, PR China; Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control, Key Laboratory of City Cluster Environmental Safety and Green Development, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, PR China
| | - Shengtao Ma
- Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, PR China; Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control, Key Laboratory of City Cluster Environmental Safety and Green Development, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, PR China
| | - Beibei Hu
- Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, PR China; Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control, Key Laboratory of City Cluster Environmental Safety and Green Development, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, PR China
| | - Yingxin Yu
- Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, PR China; Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control, Key Laboratory of City Cluster Environmental Safety and Green Development, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, PR China
| | - Taicheng An
- Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, PR China; Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control, Key Laboratory of City Cluster Environmental Safety and Green Development, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, PR China
| |
Collapse
|
39
|
Tian H, Chen L, Wu J, Zheng D, Yang Q, Ji Z, Cai J, Chen Y, Li Z. Global research into the relationship between electronic waste and health over the last 10 years: A scientometric analysis. Front Public Health 2023; 10:1069172. [PMID: 36684976 PMCID: PMC9846604 DOI: 10.3389/fpubh.2022.1069172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Accepted: 11/25/2022] [Indexed: 01/06/2023] Open
Abstract
Introduction The aims of this research were to conduct the first holistic and deep scientometric analysis of electronic waste and health and provide with the prediction of research trends and hot topics. Method A comprehensive literature search was conducted via the Web of Science Core collection databases on 26 August 2022 to identify all articles related to electronic waste and health. A total of 652 records have been extracted from the Web of Science after applying inclusion and exclusion criteria and were analyzed using bibliometrix software of R-package, VOSviewer, and CiteSpace, visualized by tables and diagrams. Result The number of publications and total citations had shown a general growth trend from 2012 to 2021, with an average annual growth rate of 23.74%. Mainland China was the significant nation with the greatest number of publications, citations, and international links. The journal publishing the most was "Science of the Total Environment" (n = 56). Huo X and Hu XJ were the top two author contributing to this field with the highest h-index (23). Over time, the focus in this field shifted to exposure to heavy metal, polychlorinated biphenyls, polybrominated biphenyl ethers, and poly- and perfluorinated alkyl substances from electronic waste, and managements, such as hydrometallurgy. Discussion By this scientometric analysis, we found that the most active country, journal, organization and author contributing to this filed, as well as high impact documents and references and research hotspots. Also, we found that the hotspots might be exposure to toxic substances from electronic waste procession, its impact on human health and relevant managements. And evironmentally friendly materials to replace heavy metal mate rials, and environmentally friendly and effective recycling methods of electronic waste need to be further studied.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | - Zhiyang Li
- Department of Thyroid, Breast, and Hernia Surgery, General Surgery, The Second Affiliated Hospital of Shantou University Medical College, Shantou, China
| |
Collapse
|
40
|
Preetam A, Jadhao PR, Naik S, Pant K, Kumar V. Supercritical fluid technology - an eco-friendly approach for resource recovery from e-waste and plastic waste: A review. Sep Purif Technol 2023. [DOI: 10.1016/j.seppur.2022.122314] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
|
41
|
Naykodi A, Patankar SC, Thorat BN. Alkaliphiles for comprehensive utilization of red mud (bauxite residue)-an alkaline waste from the alumina refinery. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:9350-9368. [PMID: 36480139 DOI: 10.1007/s11356-022-24190-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Accepted: 11/09/2022] [Indexed: 06/17/2023]
Abstract
The mining industry has powered the human endeavor to make life more innovative, flexible, and comfortable. However, it has also led to concerns due to the increasing amount of mining and associated industrial waste. Special attention is highly desired for its proper management and safe disposal in the environment. The problem has only augmented with the increase in the mining costs because of the investments needed for ecological remediation after the mining operation. It is pertinent that the targeted technologies need to be developed to utilize mining and associated industrial waste as a secondary resource to ensure sustainable mining operations. Every perceived waste is a valuable resource that is needed to be utilized to create additional value. In this review, the case of alkaline bauxite residue (red mud)-alumina refinery waste has been discussed at length. The highlight of the proposed work is to understand the importance of alkaliphile-assisted biomining-a sustainable alternative to conventional metal recovery processes. Along with the recovery of metals, pH reduction of red mud is possible through biomining, which ultimately paves the way for its complete utilization. The unique adaptation strategies of alkaliphiles make them more suitable for biomining of red mud through bioleaching, biosorption, and bioaccumulation, which have been discussed here. Furthermore, we have focused on the potential of the indigenous microflora of red mud for metal recovery in addition to its neutralization. The study of indigenous alkaliphiles from red mud, including its isolation and propagation, is crucial for the industrial-scale application of alkaliphile-based technology and has been emphasized.
Collapse
Affiliation(s)
- Ankita Naykodi
- Department of Biotechnology, Institute of Chemical Technology-IndianOil Odisha Campus, Bhubaneswar, 751013, Odisha, India
| | - Saurabh C Patankar
- Department of Chemical Engineering, Institute of Chemical Technology-IndianOil Odisha Campus, Bhubaneswar, 751013, Odisha, India
| | - Bhaskar N Thorat
- Department of Chemical Engineering, Institute of Chemical Technology, Mumbai, 400019, India.
| |
Collapse
|
42
|
Khrustalev D, Tirzhanov A, Khrustaleva A, Mustafin M, Yedrissov A. A new approach to designing easily recyclable printed circuit boards. Sci Rep 2022; 12:22199. [PMID: 36564465 PMCID: PMC9789153 DOI: 10.1038/s41598-022-26677-y] [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: 09/09/2022] [Accepted: 12/19/2022] [Indexed: 12/24/2022] Open
Abstract
Due to the ever-increasing amount of electronic waste (e-waste) worldwide, the problem of the effective disposal of printed circuit board waste (WPCB), which are environmentally hazardous, difficult to recycle and economically valuable products, has become a major environmental challenge. Conventional WPCB recycling techniques have low efficiency and require tough processing, such as heat treatment and high pressure. This paper presents a new composite material for the manufacture of printed circuit boards (PCB) that can be easily recycled into their original components and reused. In addition, the most valuable PCB components (electronic components containing precious metals) can be easily separated from the printed circuit board and reused. This study demonstrates the benefit of using biodegradable polymers as binders for PCBs in terms of environmentally friendly and efficient recycling.
Collapse
Affiliation(s)
| | - Arman Tirzhanov
- grid.443542.00000 0004 0387 8281Karaganda Economic University of Kazpotrebsouz, 100000 Karaganda, Kazakhstan
| | | | - Marlen Mustafin
- Medical University of Karaganda, 100000 Karaganda, Kazakhstan
| | - Azamat Yedrissov
- grid.428191.70000 0004 0495 7803Nazarbayev University, 010000 Nur-Sultan, Kazakhstan
| |
Collapse
|
43
|
He H, Yang B, Wu D, Gao X, Fei X. Applications of crushing and grinding-based treatments for typical metal-containing solid wastes: Detoxification and resource recovery potentials. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 314:120034. [PMID: 36030964 DOI: 10.1016/j.envpol.2022.120034] [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: 04/21/2022] [Revised: 08/14/2022] [Accepted: 08/20/2022] [Indexed: 06/15/2023]
Abstract
Metal-containing solid wastes can induce serious environmental pollution if managed improperly, but contain considerable resources. The detoxification and resource recoveries of these wastes are of both environmental and economic significances, being indispensable for circular economy. In the past decades, attempts have been made worldwide to treat these wastes. Crushing and grinding-based treatments have been increasingly applied, the operating apparatus and parameters of which depend on the waste type and treatment purpose. Based on the relevant studies, the applications of crushing and grinding on four major types of solid wastes, namely spent lithium-ion batteries (LIBs) cathode, waste printed circuit boards (WPCBs), incineration bottom ash (IBA), and incineration fly ash (IFA) are here systematically reviewed. These types of solid wastes are generated in increasing amounts, and have the potentials to release various organic and inorganic pollutants. Despite of the widely different texture, composition, and other physicochemical properties of the solid wastes, crushing and grinding have been demonstrated to be universally applicable. For each of the four wastes, the technical route that involving crushing and grinding is described with the advantages highlighted. The crushing and grinding serve either mainstream or auxiliary role in the processing of the solid wastes. This review summarizes and highlights the developments and future directions of crushing and grinding-based treatments.
Collapse
Affiliation(s)
- Hongping He
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, PR China; School of Civil and Environmental Engineering, Nanyang Technological University, 639798, Singapore
| | - Bo Yang
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, PR China
| | - Deli Wu
- State Key Laboratory of Pollution Control and Resources Reuse, School of Environmental Science & Engineering, Tongji University, Shanghai, 200092, PR China; Shanghai Institute of Pollution Control Ecological Security, Shanghai, 200092, PR China
| | - Xiaofeng Gao
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, China
| | - Xunchang Fei
- School of Civil and Environmental Engineering, Nanyang Technological University, 639798, Singapore; Residues and Resource Reclamation Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, 637141, Singapore.
| |
Collapse
|
44
|
Ikram R, Jan BM, Ahmad W, Sidek A, Khan M, Kenanakis G. Rheological Investigation of Welding Waste-Derived Graphene Oxide in Water-Based Drilling Fluids. MATERIALS (BASEL, SWITZERLAND) 2022; 15:8266. [PMID: 36431754 PMCID: PMC9696946 DOI: 10.3390/ma15228266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 11/15/2022] [Accepted: 11/18/2022] [Indexed: 06/16/2023]
Abstract
Throughout the world, the construction industry produces significant amounts of by-products and hazardous waste materials. The steel-making industry generates welding waste and dusts that are toxic to the environment and pose many economic challenges. Water-based drilling fluids (WBDF) are able to remove the drill cuttings in a wellbore and maintain the stability of the wellbore to prevent formation damage. To the best of our knowledge, this is the first study that reports the application of welding waste and its derived graphene oxide (GO) as a fluid-loss additive in drilling fluids. In this research, GO was successfully synthesized from welding waste through chemical exfoliation. The examination was confirmed using XRD, FTIR, FESEM and EDX analyses. The synthesized welding waste-derived GO in WBDF is competent in improving rheological properties by increasing plastic viscosity (PV), yield point (YP) and gel strength (GS), while reducing filtrate loss (FL) and mud cake thickness (MCT). This study shows the effect of additives such as welding waste, welding waste-derived GO and commercial GO, and their amount, on the rheological properties of WBDF. Concentrations of these additives were used at 0.01 ppb, 0.1 ppb and 0.5 ppb. Based on the experiment results, raw welding waste and welding waste-derived GO showed better performance compared with commercial GO. Among filtration properties, FL and MCT were reduced by 33.3% and 39.7% with the addition of 0.5 ppb of raw welding-waste additive, while for 0.5 ppb of welding waste-derived GO additive, FL and MCT were reduced by 26.7% and 20.9%, respectively. By recycling industrial welding waste, this research conveys state-of-the-art and low-cost drilling fluids that aid in waste management, and reduce the adverse environmental and commercial ramifications of toxic wastes.
Collapse
Affiliation(s)
- Rabia Ikram
- Department of Chemical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur 50603, Malaysia
| | - Badrul Mohamed Jan
- Department of Chemical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur 50603, Malaysia
| | - Waqas Ahmad
- Institute of Chemical Sciences, University of Peshawar, Peshawar 25120, Khyber Pukhtunkhwa, Pakistan
| | - Akhmal Sidek
- Petroleum Engineering Department, School of Chemical and Energy Engineering, Faculty of Engineering, Universiti Teknologi Malaysia, Johor Bahru 81310, Malaysia
| | - Mudasar Khan
- Institute of Chemical Sciences, University of Peshawar, Peshawar 25120, Khyber Pukhtunkhwa, Pakistan
| | - George Kenanakis
- Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas, N. Plastira 100, Vasilika Vouton, GR-700 13 Heraklion, Crete, Greece
| |
Collapse
|
45
|
Nie CC, Shi SX, Zhu XN, Jiang SQ, Gao WH, Su HL, Li CM, Lyu XJ. Enhanced cleaner flotation behavior of non-metallic particles in waste printed circuit boards: From the perspective of particle size. WASTE MANAGEMENT (NEW YORK, N.Y.) 2022; 153:167-177. [PMID: 36099727 DOI: 10.1016/j.wasman.2022.08.028] [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: 05/17/2022] [Revised: 08/24/2022] [Accepted: 08/29/2022] [Indexed: 06/15/2023]
Abstract
Flotation is an attractive method for separating the different components of waste printed circuit boards (WPCBs) due to its cleanliness and efficiency. Non-metallic particles (NMPs) with good floatability usually need to be floated, however, it is difficult to achieve complete removal. The effect of particle size on the flotation behavior of NMPs, which is usually ignored in previous studies, is concerned in this paper. Flotation tests and kinetic analysis were carried out to reveal the effect of reagent dosage on flotation characteristics of particles in narrow size fractions. As the fineness decreases, the particles are more likely to be floated. Equally, the finer the particle size, the lower the reagent dosage required to achieve the maximum recovery. For 1-0.5 mm and -0.045 mm, the maximum recovery increased from 42.16% (1500 g/t MIBC) to 97.31% (100 g/t MIBC). Therefore, the feasibility of reducing particle size by grinding to improve floatability was verified. The results show that the reduction of particle size can significantly promote its efficiency of being floated. After grinding treatment, -0.045 mm yields in each size fraction (1-0.5, 0.5-0.25, 0.25-0.125, 0.125-0.074, 0.074-0.045 mm) increased by 22.10%, 28.42%, 30.90%, 64.56%, 89.32%, resulting in an increase of 37.71%, 13.12%, 2.82%, 7.82% and 2.00% in maximum recovery, respectively. It is also proved that the particle size, rather than the resin content, has a more significant effect on the floatability of NMPs.
Collapse
Affiliation(s)
- Chun-Chen Nie
- College of Chemical and Biological Engineering, Shandong University of Science and Technology, Qingdao, Shandong 266590, China
| | - Shun-Xiang Shi
- College of Chemical and Biological Engineering, Shandong University of Science and Technology, Qingdao, Shandong 266590, China
| | - Xiang-Nan Zhu
- College of Chemical and Biological Engineering, Shandong University of Science and Technology, Qingdao, Shandong 266590, China
| | - Si-Qi Jiang
- College of Chemical and Biological Engineering, Shandong University of Science and Technology, Qingdao, Shandong 266590, China
| | - Wen-Hao Gao
- College of Chemical and Biological Engineering, Shandong University of Science and Technology, Qingdao, Shandong 266590, China
| | - Hui-Li Su
- College of Chemical and Biological Engineering, Shandong University of Science and Technology, Qingdao, Shandong 266590, China
| | - Chuan-Ming Li
- College of Chemical and Biological Engineering, Shandong University of Science and Technology, Qingdao, Shandong 266590, China
| | - Xian-Jun Lyu
- College of Chemical and Biological Engineering, Shandong University of Science and Technology, Qingdao, Shandong 266590, China.
| |
Collapse
|
46
|
Kumari R, Samadder SR. A critical review of the pre-processing and metals recovery methods from e-wastes. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 320:115887. [PMID: 35933880 DOI: 10.1016/j.jenvman.2022.115887] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 07/24/2022] [Accepted: 07/25/2022] [Indexed: 06/15/2023]
Abstract
E-wastes being potential sources of numerous valuable metals are promoted to undergo recycling and recovery under the umbrella of urban mining and circular economy. Thus, the present study provides a critical review of the technological details of different metal recycling processes, pre-treatment methods, and the advancements made in these techniques. Critical evaluation of different metal recovery techniques has also been presented based on the available life cycle assessment (LCA), techno-economic, and industrial-scale studies. The study revealed that the integrated metal recovery techniques serve better in terms of recovery efficiency and environmental performance than any single recovery technique. Also, scaling up of biometallurgical, electrochemical, and super critical fluid extraction methods needs to be promoted due to their better environmental performances.
Collapse
Affiliation(s)
- Rima Kumari
- Department of Environmental Science & Engineering, Indian Institute of Technology (Indian School of Mines), Dhanbad, 826004, India.
| | - Sukha Ranjan Samadder
- Department of Environmental Science & Engineering, Indian Institute of Technology (Indian School of Mines), Dhanbad, 826004, India.
| |
Collapse
|
47
|
Vakilchap F, Mousavi SM. Structural study and metal speciation assessments of waste PCBs and environmental implications: Outlooks for choosing efficient recycling routes. WASTE MANAGEMENT (NEW YORK, N.Y.) 2022; 151:181-194. [PMID: 35963037 DOI: 10.1016/j.wasman.2022.07.036] [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: 05/10/2022] [Revised: 06/30/2022] [Accepted: 07/27/2022] [Indexed: 06/15/2023]
Abstract
Environmental protection from risks and disposal management of discarded mobile phone printed circuit boards (MPhPCBs) is a global issue. Although recycling is proposed as a solution, it is challenging to choose a sustainable method due to the insufficient recognition from extreme structural heterogeneity of these wastes based on their types. To this end, a thorough study on the structural characterization of PCBs using different analyses and metal speciation by sequential extraction procedure were performed. Understanding these information is an essential step in order to choose efficient methods to maximize selective recycling of metals and minimize environmental implications. PCBs were found to be potent metallic reservoirs after all metal content of PCBs were precisely measured. The structural analysis results of the sample included identification of different phases, functional groups, 45.1 % of the crystalline and 54.9 % of amorphous, the mesoporous nature (pore diameter mean ∼ 7.24 nm), hydrophobic property (contact angle ∼93.4°), the positive ζ-potential of particles at pH < (isoelectric point ∼5.4) and vice versa, and the particle size that were not oversized. The metal speciation outcome indicated over 80 % of the total content of elements such as Si, Sn, Ag, Au, Sr, Al, Cr, Nd, Ca, Ba, and P was in a solid crystal structure/residual fraction, which were hard recycled. The assessment of contamination levels of waste indicated the considerable contamination for the environment at global contamination factor ∼27.7, the moderate ecological risk at potential ecological risk assessment ∼82.9, and threats to public health. In addition, the metals of Pr, Mn, and Zn pose high risks because of their risk assessment code values of 42.7 %, 36.7 %, and 33.1 %, respectively. Leaching tests proved Waste Extraction Test was an aggressive method. ANC4 proposed high level of H+ consumption are required for metal leaching in future works.
Collapse
Affiliation(s)
- Farzane Vakilchap
- Biotechnology Group, Chemical Engineering Department, Tarbiat Modares University, Tehran, Iran
| | - Seyyed Mohammad Mousavi
- Biotechnology Group, Chemical Engineering Department, Tarbiat Modares University, Tehran, Iran; Modares Environmental Research Institute, Tarbiat Modares University, Tehran, Iran.
| |
Collapse
|
48
|
Effects of particle size on the separation efficiency in a rotary-drum eddy current separator. POWDER TECHNOL 2022. [DOI: 10.1016/j.powtec.2022.117870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
49
|
Faraji F, Golmohammadzadeh R, Pickles CA. Potential and current practices of recycling waste printed circuit boards: A review of the recent progress in pyrometallurgy. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 316:115242. [PMID: 35588669 DOI: 10.1016/j.jenvman.2022.115242] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 04/22/2022] [Accepted: 05/04/2022] [Indexed: 06/15/2023]
Abstract
Over the last few decades, a substantial amount of e-waste including waste printed circuit boards (WPCBs) has been produced and is accumulating worldwide. More recently, the rate of production has increased significantly, and this trend has raised some serious concerns regarding the need to develop viable recycling methods. The presence of other materials in the WPCBs, such as ceramics and polymers, and the multi-metal nature of WPCBs all contribute to the increased complexity of any recycling process. Among the viable techniques, pyrometallurgy, with the inherent ability to process the waste independent of its composition, is a promising candidate for both rapid and large-scale treatment. In the present study, firstly, the principles of the pyrometallurgical methods for WPCB recycling are discussed. Secondly, the different unit operations of thermochemical pretreatment including incineration, pyrolysis, and molten salt processing are reviewed. Thirdly, the smelting processes for the recovery of metals from WPCBs, as well as the issues surrounding slag formation and subsequent treatment are explained. Fourthly, alternative methods for the recovery of polymers and ceramics, in addition to metal recycling, are elucidated. Fifthly, emission control techniques and the potential for energy recovery are evaluated.
Collapse
Affiliation(s)
- Fariborz Faraji
- The Robert M. Buchan Department of Mining, Queen's University, Kingston, ON, K7L 3N6, Canada.
| | - Rabeeh Golmohammadzadeh
- Department of Chemical Engineering, Monash University, Clayton, Victoria, 3800, Australia; Institute for Frontier Materials, Deakin University, Geelong, Victoria 3200, Australia
| | - Christopher A Pickles
- The Robert M. Buchan Department of Mining, Queen's University, Kingston, ON, K7L 3N6, Canada.
| |
Collapse
|
50
|
Fedorova MI, Levina AV, Zakhodyaeva YA, Voshkin AA. Extracting Transition Metals from HCl Solutions by Means of Polypropylene Glycol 425. RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY A 2022. [DOI: 10.1134/s0036024422080106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|