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Zupanc A, Install J, Weckman T, Melander MM, Heikkilä MJ, Kemell M, Honkala K, Repo T. Sequential Selective Dissolution of Coinage Metals in Recyclable Ionic Media. Angew Chem Int Ed Engl 2024; 63:e202407147. [PMID: 38742485 DOI: 10.1002/anie.202407147] [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: 04/15/2024] [Revised: 05/13/2024] [Accepted: 05/14/2024] [Indexed: 05/16/2024]
Abstract
Coinage metals Cu, Ag, and Au are essential for modern electronics and their recycling from waste materials is becoming increasingly important to guarantee the security of their supply. Designing new sustainable and selective procedures that would substitute currently used processes is crucial. Here, we describe an unprecedented approach for the sequential dissolution of single metals from Cu, Ag, and Au mixtures using biomass-derived ionic solvents and green oxidants. First, Cu can be selectively dissolved in the presence of Ag and Au with a choline chloride/urea/H2O2 mixture, followed by the dissolution of Ag in lactic acid/H2O2. Finally, the metallic Au, which is not soluble in either solution above, is dissolved in choline chloride/urea/Oxone. Subsequently, the metals were simply and quantitatively recovered from dissolutions, and the solvents were recycled and reused. The applicability of the developed approach was demonstrated by recovering metals from electronic waste substrates such as printed circuit boards, gold fingers, and solar panels. The dissolution reactions and selectivity were explored with different analytical techniques and DFT calculations. We anticipate our approach will pave a new way for the contemporary and sustainable recycling of multi-metal waste substrates.
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Affiliation(s)
- Anže Zupanc
- Department of Chemistry, Faculty of Science, University of Helsinki, A. I. Virtasen aukio 1, 00014, Helsinki, Finland
| | - Joseph Install
- Department of Chemistry, Faculty of Science, University of Helsinki, A. I. Virtasen aukio 1, 00014, Helsinki, Finland
| | - Timo Weckman
- Department of Chemistry, Nanoscience Center, University of Jyväskylä, P.O. Box 35, FI-40014, Jyväskylä, Finland
| | - Marko M Melander
- Department of Chemistry, Nanoscience Center, University of Jyväskylä, P.O. Box 35, FI-40014, Jyväskylä, Finland
| | - Mikko J Heikkilä
- Department of Chemistry, Faculty of Science, University of Helsinki, A. I. Virtasen aukio 1, 00014, Helsinki, Finland
| | - Marianna Kemell
- Department of Chemistry, Faculty of Science, University of Helsinki, A. I. Virtasen aukio 1, 00014, Helsinki, Finland
| | - Karoliina Honkala
- Department of Chemistry, Nanoscience Center, University of Jyväskylä, P.O. Box 35, FI-40014, Jyväskylä, Finland
| | - Timo Repo
- Department of Chemistry, Faculty of Science, University of Helsinki, A. I. Virtasen aukio 1, 00014, Helsinki, Finland
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Abdel-Rahim RD, Thabet M, Abdellah AR, Saleh MO, Fadl AMM, Nagiub AM, Gomaa H. pH-Dependent selective extraction of gold(iii) from synthetic solution and computer motherboard leachate using a hybrid nanocomposite. RSC Adv 2024; 14:22569-22581. [PMID: 39021457 PMCID: PMC11252653 DOI: 10.1039/d4ra04476b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2024] [Accepted: 07/10/2024] [Indexed: 07/20/2024] Open
Abstract
Recycling gold from electronic waste offers significant benefits for both environmental protection and resource sustainability. However, this process presents considerable challenges due to high costs, prolonged processing times, and interference from coexisting metals. In this study, we synthesized a hybrid mesoporous nanocomposite comprising platelets-like CoNi2S4 incorporated with g-C3N4 nanosheets (CoNi2S4@g-C3N4) for the selective recovery of gold (Au(iii)) ions from spent computer motherboards. Comprehensive characterization of the CoNi2S4@g-C3N4 nanocomposite was conducted, including its physicochemical properties, textural and structural characteristics, morphology, and elemental composition. The CoNi2S4@g-C3N4 extractor demonstrated an exceptional adsorption capacity of 200.6 mg g-1, with high selectivity at pH 2, rapid equilibrium time of 60 minutes, and satisfactory reusability for over ten cycles. Adsorption isotherm and kinetic studies revealed that the CoNi2S4@g-C3N4 nanocomposite adheres to the Langmuir adsorption model and the pseudo-second-order kinetic model for Au(iii) ion adsorption. Overall, this study introduces a viable adsorbent that shows considerable promise for industrial-scale Au(iii) extraction from e-waste.
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Affiliation(s)
- Rabeea D Abdel-Rahim
- Department of Chemistry, Faculty of Science, Al-Azhar University Assiut 71524 Egypt
| | - Mahmoud Thabet
- Department of Chemistry, Faculty of Science, Al-Azhar University Assiut 71524 Egypt
| | - Ahmed R Abdellah
- Department of Chemistry, Faculty of Science, Al-Azhar University Assiut 71524 Egypt
| | - Mohamed O Saleh
- Department of Chemistry, Faculty of Science, Al-Azhar University Assiut 71524 Egypt
| | - Ahmed M M Fadl
- Department of Chemistry, Faculty of Science, Al-Azhar University Assiut 71524 Egypt
| | - Adham M Nagiub
- Department of Chemistry, Faculty of Science, Al-Azhar University Assiut 71524 Egypt
| | - Hassanien Gomaa
- Department of Chemistry, Faculty of Science, Al-Azhar University Assiut 71524 Egypt
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Gautam P, De AK, Rao MD, Sinha I, Behera CK, Singh KK. Waste remediation: Low-temperature synthesis of hybrid Cu(OH) 2/CuO and CuO nanostructures from spent printed circuit boards and their dye degradation studies. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:41624-41637. [PMID: 37542015 DOI: 10.1007/s11356-023-29005-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Accepted: 07/22/2023] [Indexed: 08/06/2023]
Abstract
The demand for environmentally friendly and sustainable resource utilization techniques for recycling waste printed circuit boards is significant due to their status as valuable secondary resources, containing high-purity copper and precious metals. In this context, Cu(OH)2/CuO and CuO nanostructures were fabricated using alkaline precipitation and low-temperature aging methods using the strip solution originated from laboratory-scale spent mobile phone printed circuit board recovery process. XRD, FTIR, FESEM-EDX, and TEM were utilized to characterize the as-recovered nanoproducts. A hybrid structure of Cu(OH)2/CuO was formed at 70°, and monoclinic CuO phase was formed at 80 °C aging time. The results show that Cu(OH)2/CuO nanoflakes have an average crystallite size of 24.06 nm and a particle width of 22 ± 3 nm. Cu(OH)2/CuO nanoflakes formed at 70 °C aging temperature and 24-h residence time have finer crystallite and particle sizes than CuO-ridged nanospheres formed at 80 °C aging temperature. The optical band gap energy of Cu(OH)2/CuO and CuO nanostructures formed was found to be 2.28 eV and 2.22 eV, respectively. The hybrid Cu(OH)2/CuO nanostructure photocatalyzed the decomposed 97.28% rhodamine blue using a visible light source, whereas the CuO nanostructure degraded only 14.64% rhodamine blue dye under similar conditions. A surfactant-less hybrid structure is developed without the use of any chemical precursor. Thus, a high value-added product is produced using one waste material to remove another waste in wastewater treatment.
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Affiliation(s)
- Pushpa Gautam
- Department of Metallurgical Engineering, Indian Institute of Technology (Banaras Hindu University) Varanasi, Varanasi, 221005, India.
| | - Arup Kumar De
- Department of Metallurgical Engineering, Indian Institute of Technology (Banaras Hindu University) Varanasi, Varanasi, 221005, India
| | | | - Indrajit Sinha
- Department of Chemistry, Indian Institute of Technology (Banaras Hindu University) Varanasi, Varanasi, 221005, India
| | - Chhail Kumar Behera
- Department of Metallurgical Engineering, Indian Institute of Technology (Banaras Hindu University) Varanasi, Varanasi, 221005, India
| | - Kamalesh Kumar Singh
- Department of Metallurgical Engineering, Indian Institute of Technology (Banaras Hindu University) Varanasi, Varanasi, 221005, India
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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.
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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.
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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.
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Affiliation(s)
| | - Erfan Salahinejad
- Faculty of Materials Science and Engineering, K. N. Toosi University of Technology, Tehran, Iran.
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Javed A, Singh J. Process intensification for sustainable extraction of metals from e-waste: challenges and opportunities. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:9886-9919. [PMID: 36995505 DOI: 10.1007/s11356-023-26433-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Accepted: 03/09/2023] [Indexed: 06/19/2023]
Abstract
The electrical and electronic waste is expected to increase up to 74.7 million metric tons by 2030 due to the unparalleled replacement rate of electronic devices, depleting the conventional sources of valuable metals such as rare earth elements, platinum group metals, Co, Sb, Mo, Li, Ni, Cu, Ag, Sn, Au, and Cr. Most of the current techniques for recycling, recovering, and disposing of e-waste are inappropriate and therefore contaminate the land, air, and water due to the release of hazardous compounds into the environment. Hydrometallurgy and pyrometallurgy are two such conventional methods used extensively for metal recovery from waste electrical and electronic equipment (WEEE). However, environmental repercussions and higher energy requirements are the key drawbacks that prevent their widespread application. Thus, to ensure the environment and elemental sustainability, novel processes and technologies must be developed for e-waste management with enhanced recovery and reuse of the valued elements. Therefore, the goal of the current work is to examine the batch and continuous processes of metal extraction from e-waste. In addition to the conventional devices, microfluidic devices have been also analyzed for microflow metal extraction. In microfluidic devices, it has been observed that the large specific surface area and short diffusion distance of microfluidic devices are advantageous for the efficient extraction of metals. Additionally, cutting-edge technologies have been proposed to enhance the recovery, reusability, and recycling of e-waste. The current study may support decision-making by researchers in deciding the direction of future research and moving toward sustainable development.
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Affiliation(s)
- Aaliya Javed
- Department of Chemical Engineering, Sardar Vallabhbhai National Institute of Technology, Surat, Gujarat, 395007, India
| | - Jogender Singh
- Department of Chemical Engineering, Sardar Vallabhbhai National Institute of Technology, Surat, Gujarat, 395007, India.
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Lisińska M, Wojtal T, Saternus M, Willner J, Rzelewska-Piekut M, Nowacki K. Two-Stage Leaching of PCBs Using Sulfuric and Nitric Acid with the Addition of Hydrogen Peroxide and Ozone. MATERIALS (BASEL, SWITZERLAND) 2023; 17:219. [PMID: 38204071 PMCID: PMC10779704 DOI: 10.3390/ma17010219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Revised: 12/21/2023] [Accepted: 12/22/2023] [Indexed: 01/12/2024]
Abstract
The paper presents the possibility of recovering metals from printed circuit boards (PCBs) of spent mobile phones using the hydrometallurgical method. Two-stage leaching of Cu(II), Fe(III), Sn(IV), Zn(II), Ni(II) and Pb(II) with H2SO4 (2 and 5 M) and HNO3 (2 M) with the addition of H2O2 (10 and 30%) and O3 (9 or 15 g/h) was conducted at various process conditions (temperature-313, 333 and 353 K, time-60, 120, 240, 300 min, type and concentration of leaching agent, type and concentration of oxidant, solid-liquid ratio (S/L)), allowing for a high or total metals leaching rate. The use of two leaching stages allows for the preservation of selectivity, separation and recovery of metals: in the first stage of Fe(III), Sn(IV) and in the second stage of the remaining tested metal ions, i.e., Cu(II), Zn(II), Ni(II) and Pb(II). Removing Fe from the tested PCBs' material at the beginning of the process eliminates the need to use magnetic methods, the purpose of which is to separate magnetic metal particles (ferrous) from non-magnetic (non-ferrous) particles; these procedures involve high operating costs. Since the leaching of Cu(II) ions with sulfuric(VI) acid practically does not occur (less than 1%), this allows for almost complete transfer of these ions into the solution in the second stage of leaching. Moreover, to speed up the process and not generate too many waste solutions, oxidants in the form of hydrogen peroxide and ozone were used. The best degree of leaching of all tested metal ions was obtained when 2 M sulfuric(VI) acid at 353 K was used in the 1st research stage, and 2 M nitric(V) acid and 9 g/h O3 at 298 K in the 2nd stage of leaching, which allowed it to be totally leached 100% of Fe(III), Cu(II), Sn(IV), Zn(II), Ni(II) and 90% Pb(II).
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Affiliation(s)
- Magdalena Lisińska
- Zakłady Mechaniczne „WIROMET” S.A., ul. Wyzwolenia 27, 43-190 Mikołów, Poland;
| | - Tomasz Wojtal
- Faculty of Materials Engineering, Silesian University of Technology, ul. Krasińskiego 8, 40-019 Katowice, Poland; (T.W.); (J.W.); (K.N.)
| | - Mariola Saternus
- Faculty of Materials Engineering, Silesian University of Technology, ul. Krasińskiego 8, 40-019 Katowice, Poland; (T.W.); (J.W.); (K.N.)
| | - Joanna Willner
- Faculty of Materials Engineering, Silesian University of Technology, ul. Krasińskiego 8, 40-019 Katowice, Poland; (T.W.); (J.W.); (K.N.)
| | - Martyna Rzelewska-Piekut
- Institute of Chemical Technology and Engineering, Poznan University of Technology, ul. Berdychowo 4, 60-965 Poznan, Poland;
| | - Krzysztof Nowacki
- Faculty of Materials Engineering, Silesian University of Technology, ul. Krasińskiego 8, 40-019 Katowice, Poland; (T.W.); (J.W.); (K.N.)
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Rao MD, Meshram RB, Singh KK, Morrison CA, Love JB. Life cycle analysis on sequential recovery of copper and gold from waste printed circuit boards. WASTE MANAGEMENT (NEW YORK, N.Y.) 2023; 171:621-627. [PMID: 37837909 DOI: 10.1016/j.wasman.2023.10.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2023] [Revised: 09/21/2023] [Accepted: 10/05/2023] [Indexed: 10/16/2023]
Abstract
Informal recycling activities of waste printed circuit boards, such as pyrolysis and landfilling, cause severe environmental harm to society. Pyrolysis of resin and polymer fraction leads to the generation of toxic effluents, and landfilling causes the leaching of heavy metals into the groundwater. A sustainable and eco-friendly way to recover base and precious elements will be an economically attractive option. Current research studied the cradle-to-gate environmental impacts of the sequential recovery of copper and gold through delamination, leaching, solvent extraction, electrowinning and cementation from waste printed circuit boards with the help of life cycle assessment.GaBi software was utilized to assess environmental impacts such as global warming, abiotic depletion (fossil), acidification potential and human toxicity potential during the process. Inventory data was collected by conducting several experiments and from optimizing parameters for recycling and separating 4.53 g of copper and 2.25 mg of gold from 16 g of component-free waste printed circuit boards. Results indicate that the chemical pre-treatment or delamination process for separating metal clads from the non-metallic fraction is primarily involved in the impact category. The higher impact during delamination is due to electricity consumption. The proposed study also corroborates the industrial viability of recycling valuable metals from waste printed circuit boards to minimize the environmental impacts. The outcomes of this work could be beneficial in creating the environmental guiding principle for WPCBs recycling plants.
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Affiliation(s)
- Mudila Dhanunjaya Rao
- CSIR-National Metallurgical Laboratory, Jamshedpur 831007, India; Department of Metallurgical Engineering, Indian Institute of Technology (Banaras Hindu University), Varanasi 221005, India.
| | - Rohit B Meshram
- CSIR-National Metallurgical Laboratory, Jamshedpur 831007, India
| | - Kamalesh K Singh
- Department of Metallurgical Engineering, Indian Institute of Technology (Banaras Hindu University), Varanasi 221005, India.
| | - Carole A Morrison
- EaStCHEM School of Chemistry, University of Edinburgh, Joseph Black Building, The King's Buildings, David Brewster Road, Edinburgh EH9 3FJ, UK
| | - Jason B Love
- EaStCHEM School of Chemistry, University of Edinburgh, Joseph Black Building, The King's Buildings, David Brewster Road, Edinburgh EH9 3FJ, UK
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Cenci MP, Eidelwein EM, Veit HM. Composition and recycling of smartphones: A mini-review on gaps and opportunities. WASTE MANAGEMENT & RESEARCH : THE JOURNAL OF THE INTERNATIONAL SOLID WASTES AND PUBLIC CLEANSING ASSOCIATION, ISWA 2023; 41:1512-1528. [PMID: 37052313 DOI: 10.1177/0734242x231164324] [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: 06/19/2023]
Abstract
After more than a decade since smartphones became consolidated in the market, many recycling solutions have been proposed to deal with them. To continue developing useful solutions and enable adjustment of routes, this mini-review aims to analyse the current research scenario, presenting relevant gaps, trends and opportunities. From a structured searching and screening procedure, a vast source of data was arranged and is available to extract useful information (43 studies on composition and 93 studies on recycling). The study provides discussions about the history of smartphone development, constituent materials and recycling methods for different components, comparisons between feature phones and smartphones and others. Among some conclusions, the authors highlight the lack of studies on pre-extractive methods, green chemistry, recovery of critical and precious metals, determination of priority materials for recovery and solutions for entire devices. In the end, a list containing six research gaps for composition studies and seven research gaps for recycling studies is provided and may be seen as opportunities for future research.
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Affiliation(s)
- Marcelo Pilotto Cenci
- LACOR, Department of Materials Engineering, Federal University of Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
| | - Estela Moschetta Eidelwein
- LACOR, Department of Materials Engineering, Federal University of Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
| | - Hugo Marcelo Veit
- LACOR, Department of Materials Engineering, Federal University of Rio Grande do Sul (UFRGS), Porto Alegre, Brazil
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Shakil S, Arooj A, Fatima S, Sadef Y. Geochemical distribution and environmental risk assessment of trace metals in groundwater released from e-waste management activities in Lahore, Pakistan. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2023; 45:3699-3714. [PMID: 36482136 DOI: 10.1007/s10653-022-01431-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Accepted: 11/04/2022] [Indexed: 06/01/2023]
Abstract
Non-sustainable e-waste recycling and dumping activities release trace metals into the ambient environment where they may threaten the biological communities and human health. A total of 45 groundwater and 21 leachate samples were collected from seven recycling, seven dumping, and one reference site in Lahore, Pakistan, and analyzed for Cu, Pb, Zn, Cd, Mn, and Fe in atomic absorption spectrophotometer. Comparing the results with the World Health Organization (WHO) standards of drinking water, only the concentrations of Cu, Zn, Mn, and Fe at all sites were found to be within the permissible limits, i.e., 2, 3, 0.5, and 1 mg/L, respectively. In leachates, only Cd and Mn at one site (0.204 and 8.636 mg/L, respectively) exceeded the allowable limits of National Environmental Quality Standards of Municipal and Liquid industrial effluents. Geo-accumulation index, contamination factor, contamination degree, and pollution load index values showed no to moderate contamination. The ecological risk index did not exceed 150, depicting low risk to nearby biological communities. The non-carcinogenic health risk assessment showed a hazard index value greater than 1 at all sites for children (2.04) and adults (1.52), with Pb being the major contributor to adverse health impacts via ingestion and dermal route. Children (1.21 × 10-4) were at a more significant threat of carcinogenic risk from Pb and Cd as compared to adults (8.10 × 10-5). Therefore, there is a dire need to introduce sustainable e-waste recycling and managing techniques to reduce further groundwater contamination via the percolation of trace metals and to reduce the current contamination level.
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Affiliation(s)
- Sidra Shakil
- College of Earth and Environmental Sciences, University of Punjab, Quaid-E-Azam Campus, Lahore, 54000, Pakistan.
| | - Aqsa Arooj
- College of Earth and Environmental Sciences, University of Punjab, Quaid-E-Azam Campus, Lahore, 54000, Pakistan
| | - Sidra Fatima
- College of Earth and Environmental Sciences, University of Punjab, Quaid-E-Azam Campus, Lahore, 54000, Pakistan
| | - Yumna Sadef
- College of Earth and Environmental Sciences, University of Punjab, Quaid-E-Azam Campus, Lahore, 54000, Pakistan
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Kahar INS, Othman N, Noah NFM, Suliman SS. Recovery of copper and silver from industrial e-waste leached solutions using sustainable liquid membrane technology: a review. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:66445-66472. [PMID: 37101217 DOI: 10.1007/s11356-023-26951-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Accepted: 04/06/2023] [Indexed: 05/25/2023]
Abstract
Waste electrical and electronic equipment or e-waste has recently emerged as a significant global concern. This waste contains various valuable metals, and via recycling, it could become a sustainable resource of metals (viz. copper, silver, gold, and others) while reducing reliance on virgin mining. Copper and silver with their superior electrical and thermal conductivity have been reviewed due to their high demand. Recovering these metals will be beneficial to attain the current needs. Liquid membrane technology has appeared as a viable option for treating e-waste from various industries as a simultaneous extraction and stripping process. It also includes extensive research on biotechnology, chemical and pharmaceutical, environmental engineering, pulp and paper, textile, food processing, and wastewater treatment. The success of this process depends more on the selection of organic and stripping phases. In this review, the use of liquid membrane technology in treating/recovering copper and silver from industrial e-waste leached solutions was highlighted. It also assembles critical information on the organic phase (carrier and diluent) and stripping phase in liquid membrane formulation for selective copper and silver. In addition, the utilization of green diluent, ionic liquids, and synergist carrier was also included since it gained prominence attention latterly. The future prospects and challenges of this technology were also discussed to ensure the industrialization of technology. Herein, a potential process flowchart for the valorization of e-waste is also proposed.
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Affiliation(s)
- Izzat Naim Shamsul Kahar
- School of Chemical and Energy Engineering, Faculty of Engineering, Universiti Teknologi Malaysia, 81310, Skudai, Johor, Malaysia
| | - Norasikin Othman
- School of Chemical and Energy Engineering, Faculty of Engineering, Universiti Teknologi Malaysia, 81310, Skudai, Johor, Malaysia.
- Centre of Lipids Engineering and Applied Research (CLEAR), Ibnu Sina Institute for Scientific and Industrial Research (ISI-SIR), Universiti Teknologi Malaysia, 81310, Skudai, Johor, Malaysia.
| | - Norul Fatiha Mohamed Noah
- School of Chemical and Energy Engineering, Faculty of Engineering, Universiti Teknologi Malaysia, 81310, Skudai, Johor, Malaysia
- Centre of Lipids Engineering and Applied Research (CLEAR), Ibnu Sina Institute for Scientific and Industrial Research (ISI-SIR), Universiti Teknologi Malaysia, 81310, Skudai, Johor, Malaysia
| | - Sazmin Sufi Suliman
- School of Chemical and Energy Engineering, Faculty of Engineering, Universiti Teknologi Malaysia, 81310, Skudai, Johor, Malaysia
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Nogueira AF, Carreira AR, Vargas SJ, Passos H, Schaeffer N, Coutinho JA. Simple gold recovery from e-waste leachate by selective precipitation using a quaternary ammonium salt. Sep Purif Technol 2023. [DOI: 10.1016/j.seppur.2023.123797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/09/2023]
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Xia Q, Song Q, Xu Z. Electrorefining and electrodeposition for metal separation and purification from polymetallic concentrates after waste printed circuit board smelting. WASTE MANAGEMENT (NEW YORK, N.Y.) 2023; 158:146-152. [PMID: 36709680 DOI: 10.1016/j.wasman.2023.01.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Revised: 01/01/2023] [Accepted: 01/13/2023] [Indexed: 06/18/2023]
Abstract
Multi metal recycling from waste printed circuit boards (WPCBs) is attractive for resource conservation and sustainability. While smelting is commonly adopted to produce polymetallic concentrates from WPCBs, current processes cost oxidation smelting and fire refining followed by electrorefining to deport co-existing base metals and recover copper, which can cause substantial metal losses, long steps, and lack of effective methods for subsequent base metal recycling. Here, direct electrorefining of polymetallic concentrates (Cu-Ni-Fe-Pb-sn-Au-Ag) combined with electrodeposition was investigated to realize multi metal separation and purification. It was found that direct electrorefining of concentrates in H2SO4/CuSO4 electrolyte at 0.4 V realized >98% base metal dissolution and copper production (∼99% purity), serving as a combined metal leaching and copper electrowinning procedure. PbSO4-SnO2-Cu5FeS4 precipitate was formed in anode slime, with Ag-Au enriched by 8.5-61 times. Analysis on subsequent selective metal electrodeposition revealed the blocking effect of Zn2+ and overlapped potential region of Fe2+-Ni2+, emphasizing the importance of Zn and Fe pre-separation during smelting and chemical precipitation. Electrodeposition experiments demonstrated high selectivity for Cu and Ni at 0.05 and -0.7 V, where Ni2+ shows complex electroreduction behaviors. The proposed process can serve as an alternative feasible route for multi metal recycling from WPCBs.
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Affiliation(s)
- Qinyi Xia
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, People's Republic of China
| | - Qingming Song
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, People's Republic of China
| | - Zhenming Xu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, People's Republic of China.
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14
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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.
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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.
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15
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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]
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16
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Ruiu A, Bouilhac C, Gimello O, Seaudeau-Pirouley K, Senila M, Jänisch T, Lacroix-Desmazes P. Synthesis and Phase Behavior of a Platform of CO2-Soluble Functional Gradient Copolymers Bearing Metal-Complexing Units. Polymers (Basel) 2022; 14:polym14132698. [PMID: 35808744 PMCID: PMC9269141 DOI: 10.3390/polym14132698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 06/24/2022] [Accepted: 06/26/2022] [Indexed: 12/10/2022] Open
Abstract
The synthesis and characterization of a platform of novel functional fluorinated gradient copolymers soluble in liquid and supercritical CO2 is reported. These functional copolymers are bearing different types of complexing units (pyridine, triphenylphosphine, acetylacetate, thioacetate, and thiol) which are well-known ligands for various metals. They have been prepared by reversible addition–fragmentation chain-transfer (RAFT) polymerization in order to obtain well-defined gradient copolymers. The copolymers have been characterized by proton nuclear magnetic resonance (1H-NMR) spectroscopy, matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry, thermal gravimetric analysis (TGA), dynamical scanning calorimetry (DSC) and cloud point measurements in dense CO2. All the investigated metal-complexing copolymers are soluble in dense CO2 under mild conditions (pressure lower than 30 MPa up to 65 °C), confirming their potential applications in processes such as metal-catalyzed reactions in dense CO2, metal impregnation, (e.g., preparation of supported catalysts) or metal extraction from various substrates (solid or liquid effluents). Particularly, it opens the door to greener and less energy-demanding processes for the recovery of metals from spent catalysts compared to more conventional pyro- and hydro-metallurgical methods.
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Affiliation(s)
- Andrea Ruiu
- ICGM, Univ. Montpellier, CNRS, ENSCM, 34293 Montpellier, France; (A.R.); (O.G.)
| | - Cécile Bouilhac
- ICGM, Univ. Montpellier, CNRS, ENSCM, 34293 Montpellier, France; (A.R.); (O.G.)
- Correspondence: (C.B.); (P.L.-D.)
| | - Olinda Gimello
- ICGM, Univ. Montpellier, CNRS, ENSCM, 34293 Montpellier, France; (A.R.); (O.G.)
| | | | - Marin Senila
- INCDO INOE 2000, Research Institute for Analytical Instrumentation, ICIA, 400293 Cluj-Napoca, Romania;
| | - Thorsten Jänisch
- Fraunhofer Institute for Chemical Technology, 76327 Pfinztal, Germany;
| | - Patrick Lacroix-Desmazes
- ICGM, Univ. Montpellier, CNRS, ENSCM, 34293 Montpellier, France; (A.R.); (O.G.)
- Correspondence: (C.B.); (P.L.-D.)
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17
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Advancements in the field of electronic waste Recycling: Critical assessment of chemical route for generation of energy and valuable products coupled with metal recovery. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2022.120773] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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18
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Abidli A, Huang Y, Ben Rejeb Z, Zaoui A, Park CB. Sustainable and efficient technologies for removal and recovery of toxic and valuable metals from wastewater: Recent progress, challenges, and future perspectives. CHEMOSPHERE 2022; 292:133102. [PMID: 34914948 DOI: 10.1016/j.chemosphere.2021.133102] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2021] [Revised: 11/08/2021] [Accepted: 11/25/2021] [Indexed: 06/14/2023]
Abstract
Due to their numerous effects on human health and the natural environment, water contamination with heavy metals and metalloids, caused by their extensive use in various technologies and industrial applications, continues to be a huge ecological issue that needs to be urgently tackled. Additionally, within the circular economy management framework, the recovery and recycling of metals-based waste as high value-added products (VAPs) is of great interest, owing to their high cost and the continuous depletion of their reserves and natural sources. This paper reviews the state-of-the-art technologies developed for the removal and recovery of metal pollutants from wastewater by providing an in-depth understanding of their remediation mechanisms, while analyzing and critically discussing the recent key advances regarding these treatment methods, their practical implementation and integration, as well as evaluating their advantages and remaining limitations. Herein, various treatment techniques are covered, including adsorption, reduction/oxidation, ion exchange, membrane separation technologies, solvents extraction, chemical precipitation/co-precipitation, coagulation-flocculation, flotation, and bioremediation. A particular emphasis is placed on full recovery of the captured metal pollutants in various reusable forms as metal-based VAPs, mainly as solid precipitates, which is a powerful tool that offers substantial enhancement of the remediation processes' sustainability and cost-effectiveness. At the end, we have identified some prospective research directions for future work on this topic, while presenting some recommendations that can promote sustainability and economic feasibility of the existing treatment technologies.
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Affiliation(s)
- Abdelnasser Abidli
- Microcellular Plastics Manufacturing Laboratory (MPML), Department of Mechanical and Industrial Engineering, Faculty of Applied Science and Engineering, University of Toronto, 5 King's College Road, Toronto, Ontario, M5S 3G8, Canada; Institute for Water Innovation (IWI), Faculty of Applied Science and Engineering, University of Toronto, 55 St. George Street, Toronto, Ontario, M5S 1A4, Canada.
| | - Yifeng Huang
- Microcellular Plastics Manufacturing Laboratory (MPML), Department of Mechanical and Industrial Engineering, Faculty of Applied Science and Engineering, University of Toronto, 5 King's College Road, Toronto, Ontario, M5S 3G8, Canada; Institute for Water Innovation (IWI), Faculty of Applied Science and Engineering, University of Toronto, 55 St. George Street, Toronto, Ontario, M5S 1A4, Canada; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, Heilongjiang, China
| | - Zeineb Ben Rejeb
- Microcellular Plastics Manufacturing Laboratory (MPML), Department of Mechanical and Industrial Engineering, Faculty of Applied Science and Engineering, University of Toronto, 5 King's College Road, Toronto, Ontario, M5S 3G8, Canada
| | - Aniss Zaoui
- Microcellular Plastics Manufacturing Laboratory (MPML), Department of Mechanical and Industrial Engineering, Faculty of Applied Science and Engineering, University of Toronto, 5 King's College Road, Toronto, Ontario, M5S 3G8, Canada
| | - Chul B Park
- Microcellular Plastics Manufacturing Laboratory (MPML), Department of Mechanical and Industrial Engineering, Faculty of Applied Science and Engineering, University of Toronto, 5 King's College Road, Toronto, Ontario, M5S 3G8, Canada; Institute for Water Innovation (IWI), Faculty of Applied Science and Engineering, University of Toronto, 55 St. George Street, Toronto, Ontario, M5S 1A4, Canada.
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19
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Wu T, Lin Z, Wu H, Zhu C, Komiyama T, Shi J, Liang R. Selective and sensitive adsorption of Au(III) by poly-N-phenylglycine. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2022.120604] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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20
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Separation of palladium and silver from E-waste leachate: effect of nitric acid concentration on adsorption to Thiol scavenger. CHEMICAL ENGINEERING JOURNAL ADVANCES 2022. [DOI: 10.1016/j.ceja.2022.100280] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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21
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Liu X, Wu Y, Wang Y, Wei H, Guo J, Yang Y. Extraction of Au( iii) from hydrochloric acid media using a novel amide-based ionic liquid. NEW J CHEM 2022. [DOI: 10.1039/d2nj04437d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
A study on the performance of selective extraction of Au(iii) using a novel amide-based IL.
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Affiliation(s)
- Xiaoxia Liu
- Key Laboratory for Special Functional Aggregate Materials of Education Miniatry, School of Chemistry and Chemical Engineering, Shandong University, Jinan, 250100, P. R. China
| | - Yang Wu
- Key Laboratory for Special Functional Aggregate Materials of Education Miniatry, School of Chemistry and Chemical Engineering, Shandong University, Jinan, 250100, P. R. China
| | - Yangyang Wang
- Key Laboratory for Special Functional Aggregate Materials of Education Miniatry, School of Chemistry and Chemical Engineering, Shandong University, Jinan, 250100, P. R. China
| | - Huiying Wei
- Key Laboratory for Special Functional Aggregate Materials of Education Miniatry, School of Chemistry and Chemical Engineering, Shandong University, Jinan, 250100, P. R. China
| | - Jinxin Guo
- Key Laboratory for Special Functional Aggregate Materials of Education Miniatry, School of Chemistry and Chemical Engineering, Shandong University, Jinan, 250100, P. R. China
| | - Yanzhao Yang
- Key Laboratory for Special Functional Aggregate Materials of Education Miniatry, School of Chemistry and Chemical Engineering, Shandong University, Jinan, 250100, P. R. China
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22
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Islam A, Roy S, Teo SH, Khandaker S, Taufiq-Yap YH, Aziz AA, Monir MU, Rashid U, Vo DVN, Ibrahim ML, Znad H, Awual MR. Functional novel ligand based palladium(II) separation and recovery from e-waste using solvent-ligand approach. Colloids Surf A Physicochem Eng Asp 2022. [DOI: 10.1016/j.colsurfa.2021.127767] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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23
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Radzyminska-Lenarcik E, Pyszka I, Kosciuszko A. Separation and Recovery of Gold(III), Palladium(II) and Platinum(IV) by Solvent Extraction Using a New β-Diketone Derivative from Acidic Solutions. MATERIALS 2021; 14:ma14164436. [PMID: 34442959 PMCID: PMC8399779 DOI: 10.3390/ma14164436] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 08/04/2021] [Accepted: 08/06/2021] [Indexed: 12/02/2022]
Abstract
This study indicates that a new amine derivative of β-diketone (EDAB-acac) can be successfully used in an acidic medium (HCl) to separate a mixture containing Au(III), Pd(II), and Pt(IV) ions using solvent extraction. The study was conducted in single and ternary model solutions. The impact of acid concentration and the type of solvent (toluene, chloroform, methylene chloride, 2-ethylhexanol) on separation efficiency was discussed. It has been shown that increasing the HCl concentration in the aqueous phase does not favor extraction. In contrast, solvents with high donor numbers (methylene chloride, 2-ethylhexanol) increase both the extraction percentage of Pd and Au as well as the separation coefficients of Pd in relation to Au and Pt. The palladium(II) and gold(III) (which form 4-coordinated planar [MCl4]2− complexes) are extracted most efficiently, Pd(II) (87–93%) and Au(III) (56–62%). The stripping of Au(III), Pd(II), and Pt(IV) ions from the EDAB-acac-methylene chloride phase was also investigated using 0.5 M ammonia aq., mineral acid (5 M HCl, 5 M HNO3), 0.1 M thiourea in HCl and 0.5 M ammonium thiocyanate. A 3-step stripping process was proposed for the recovery of Pd(II), Au(III), and Pt(IV) from the Pd-Au-Pt mixture in the EDAB-acac-methylene chloride system. In the first stage, the aqueous phase is treated with 5 M HNO3 (Pt separation), followed by the application of 0.5 M ammonia (Pd separation) and, finally, 0.1 M thiourea in HCl (Au separation). The solvent extraction with EDAB-acac in acidic medium (HCl) can be used for separation of Pd(II) and Au(III) ions from e-waste leach solutions.
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Affiliation(s)
- Elzbieta Radzyminska-Lenarcik
- Faculty of Chemical Technology and Engineering, UTP University of Science and Technology, Seminaryjna 3, 85-326 Bydgoszcz, Poland;
- Correspondence: ; Tel.: +48-52-374-9065
| | - Ilona Pyszka
- Faculty of Chemical Technology and Engineering, UTP University of Science and Technology, Seminaryjna 3, 85-326 Bydgoszcz, Poland;
| | - Artur Kosciuszko
- Faculty of Mechanical Engineering, UTP University of Science and Technology, Al. Prof. S. Kaliskiego 7, 85-796 Bydgoszcz, Poland;
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24
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Hydrometallurgical Recycling Process for Mobile Phone Printed Circuit Boards Using Ozone. METALS 2021. [DOI: 10.3390/met11050820] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Printed circuit boards (PCBs) can be an important source of non-ferrous metals (Al, Sn, Zn, and Ni) and precious metals (Au, Ag, Cu, and Pd). With the continuous increase in demand for metals due to the depletion of ores, recycling of this waste is becoming an attractive alternative. The printed circuits also contain hazardous metals, such as Pb, Hg, As, and Cd. Due to the huge increase in the amount of e-waste, the processing of printed circuit boards for metal recovery and proper handling of hazardous substances has a positive effect on the environment. Pyrometallurgical and hydrometallurgical methods are used for the treatment of this waste. Various oxidizing agents are used in the hydrometallurgical processes, including ozone. PCBs from mobile phones were assessed for the recovery of Cu, Sn, and precious metals. The ground and sieved materials were leached in nitric acid, hydrochloric acid, and sulfuric acid at various process parameters, such as leaching time, leaching agent, and temperature. It was found that the best result was obtained using hydrochloric acid with the addition of ozone at 353 K for a period of 4 h to obtain 68.45 g/dm3 of copper. Preliminary results of electrolysis and cementation are also presented.
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