1
|
Ding A, Li M, Liu C, Chee TS, Yan Q, Lei L, Xiao C. Recovering palladium and gold by peroxydisulfate-based advanced oxidation process. SCIENCE ADVANCES 2024; 10:eadm9311. [PMID: 38787950 DOI: 10.1126/sciadv.adm9311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Accepted: 04/22/2024] [Indexed: 05/26/2024]
Abstract
Palladium (Pd) and gold (Au) are the most often used precious metals (PMs) in industrial catalysis and electronics. Green recycling of Pd and Au is crucial and difficult. Here, we report a peroxydisulfate (PDS)-based advanced oxidation process (AOPs) for selectively recovering Pd and Au from spent catalysts. The PDS/NaCl photochemical system achieves complete dissolution of Pd and Au. By introducing Fe(II), the PDS/FeCl2·4H2O solution functioned as Fenton-like system, enhancing the leaching efficiency without xenon (Xe) lamp irradiation. Electron paramagnetic resonance (EPR), 18O isotope tracing experiments, and density functional theory calculations revealed that the reactive oxidation species of SO4·-, ·OH, and Fe(IV)═O were responsible for the oxidative dissolution process. Lixiviant leaching and one-step electrodeposition recovered high-purity Pd and Au. Strong acids, poisonous cyanide, and volatile organic solvents were not used during the whole recovery, which enables an efficient and sustainable precious metal recovery approach and encourage AOP technology for secondary resource recycling.
Collapse
Affiliation(s)
- Anting Ding
- College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310058, China
- Institute of Zhejiang University-Quzhou, Quzhou 324000, China
| | - Ming Li
- Institute of Zhejiang University-Quzhou, Quzhou 324000, China
| | - Chuanying Liu
- Institute of Zhejiang University-Quzhou, Quzhou 324000, China
| | - Tien-Shee Chee
- Department of Materials Science and Engineering, KAIST, Yuseong-gu, Daejeon 341, Republic of Korea
| | - Qibin Yan
- College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310058, China
| | - Lecheng Lei
- College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310058, China
- Institute of Zhejiang University-Quzhou, Quzhou 324000, China
| | - Chengliang Xiao
- College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310058, China
- Institute of Zhejiang University-Quzhou, Quzhou 324000, China
| |
Collapse
|
2
|
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: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.
Collapse
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
| |
Collapse
|
3
|
Nag A, Morrison CA, Love JB. Rapid Dissolution of Gold in Alcohols by In-Situ Generation of Halogens. CHEMSUSCHEM 2024:e202301695. [PMID: 38412014 DOI: 10.1002/cssc.202301695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Revised: 02/09/2024] [Accepted: 02/27/2024] [Indexed: 02/28/2024]
Abstract
The dissolution of elemental gold is a fundamental step in its recycling by hydrometallurgy but has a significant environmental impact due to the use of strong acids or highly toxic reagents. Herein, it is shown that mixtures of acetyl halides and hydrogen peroxide in alcohols promote the rapid room-temperature dissolution of gold by halogenation to form Au(III) metalates. After leaching, distillation of the alcohol and re-dissolution in dilute HCl, the gold was refined through its precipitation by a simple diamide ligand; this method was also applied to separate gold from a mixture of metals. The leaching process is rapid, avoids the use of highly toxic materials and corrosive acids, and can be integrated into selective separation processes, so has the potential to be used in the purification of gold from ores, spent catalysts, and electronic and nano-waste.
Collapse
Affiliation(s)
- Abhijit Nag
- EaStCHEM School of Chemistry, University of Edinburgh, Edinburgh, EH9 3FJ, UK
| | - Carole A Morrison
- EaStCHEM School of Chemistry, University of Edinburgh, Edinburgh, EH9 3FJ, UK
| | - Jason B Love
- EaStCHEM School of Chemistry, University of Edinburgh, Edinburgh, EH9 3FJ, UK
| |
Collapse
|
4
|
Nag A, Singh MK, Morrison CA, Love JB. Efficient Recycling of Gold and Copper from Electronic Waste by Selective Precipitation. Angew Chem Int Ed Engl 2023; 62:e202308356. [PMID: 37594475 PMCID: PMC10952234 DOI: 10.1002/anie.202308356] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Revised: 08/18/2023] [Accepted: 08/18/2023] [Indexed: 08/19/2023]
Abstract
The recycling of metals from electronic waste (e-waste) using efficient, selective, and sustainable processes is integral to circular economy and net-zero aspirations. Herein, we report a new method for the selective precipitation of metals such as gold and copper that offsets the use of organic solvents that are traditionally employed in solvent extraction processes. We show that gold can be selectively precipitated from a mixture of metals in hydrochloric acid solution using triphenylphosphine oxide (TPPO), as the complex [(TPPO)4 (H5 O2 )][AuCl4 ]. By tuning the acid concentration, controlled precipitation of gold, zinc and iron can be achieved. We also show that copper can be selectively precipitated using 2,3-pyrazinedicarboxylic acid (2,3-PDCA), as the complex [Cu(2,3-PDCA-H)2 ]n ⋅ 2n(H2 O). The combination of these two precipitation methods resulted in the recovery of 99.5 % of the Au and 98.5 % of the Cu present in the connector pins of an end-of-life computer processing unit. The selectivity of these precipitation processes, combined with their straightforward operation and the ability to recycle and reuse the precipitants, suggests potential industrial uses in the purification of gold and copper from e-waste.
Collapse
Affiliation(s)
- Abhijit Nag
- EaStCHEM School of ChemistryUniversity of EdinburghEH9 3FJEdinburghUK
| | - Mukesh K. Singh
- EaStCHEM School of ChemistryUniversity of EdinburghEH9 3FJEdinburghUK
| | | | - Jason B. Love
- EaStCHEM School of ChemistryUniversity of EdinburghEH9 3FJEdinburghUK
| |
Collapse
|
5
|
Zupanc A, Install J, Jereb M, Repo T. Sustainable and Selective Modern Methods of Noble Metal Recycling. Angew Chem Int Ed Engl 2023; 62:e202214453. [PMID: 36409274 PMCID: PMC10107291 DOI: 10.1002/anie.202214453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 11/20/2022] [Accepted: 11/21/2022] [Indexed: 11/23/2022]
Abstract
Noble metals exhibit broad arrange of applications in industry and several aspects of human life which are becoming more and more prevalent in modern times. Due to their limited sources and constantly and consistently expanding demand, recycling of secondary and waste materials must accompany the traditional mineral extractions. This Minireview covers the most recent solvometallurgical developments in regeneration of Pd, Pt, Rh, Ru, Ir, Os, Ag and Au with emphasis on sustainability and selectivity. Processing-by selective oxidative dissolution, reductive precipitation, solvent extraction, co-precipitation, membrane transfer and trapping to solid media-of eligible multi-metal substrates for recycling from waste printed circuit boards to end-of-life automotive catalysts are discussed. Outlook for possible future direction for noble metal recycling is proposed with emphasis on sustainable approaches.
Collapse
Affiliation(s)
- Anže Zupanc
- Department of Chemistry, University of Helsinki, P.O. Box 55 (A. I. Virtasen aukio 1), 00014, Helsinki, Finland.,Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, 1000, Ljubljana, Slovenia
| | - Joseph Install
- Department of Chemistry, University of Helsinki, P.O. Box 55 (A. I. Virtasen aukio 1), 00014, Helsinki, Finland
| | - Marjan Jereb
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, 1000, Ljubljana, Slovenia
| | - Timo Repo
- Department of Chemistry, University of Helsinki, P.O. Box 55 (A. I. Virtasen aukio 1), 00014, Helsinki, Finland
| |
Collapse
|