Journal of Environmental Chemical Engineering
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2025
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IF 7.2
Feng Feng,Jiaying Zhang,Lu Yu,Haixin Wang,Heda Ding,Jifan Cheng,Miaolan Wang,Fangfang Chen,Jiahui Zhang,Lingling Guo,Chunshan Lu,Qunfeng Zhang,Xiaonian Li
In order to develop an efficient and environmentally friendly method for the recovery of precious metals, a functionalized ionic liquid containing free radicals (1-methyl-3-(2-oxo-2-(2,2,6,6-tetramethyl-1-oxo-4-piperidinoxy) butyl) imidazole trichloro-1-bromoaluminium salt) was designed and synthesized. This was achieved by combining 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO), which possesses oxidizing properties, with halide ions that exhibit complexing abilities. Notably, under optimal conditions, a maximum gold dissolution rate of 100 % was attained. X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and Raman spectroscopy analyses were conducted to elucidate the dissolution mechanism. Ultimately, these functionalized ionic liquids can be utilized for the dissolution of precious metals in CPU pins and waste catalysts. This study presents an effective approach for the recovery of precious metals.
研究领域:
化学
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材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
Heliyon
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2022
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IF 3.776
Xiang Liu,Yongliang Wang,Li Xiao,Licheng Ma,Peiwei Han,Shufeng Ye
Gold is a valued, critical element whose chemical activation or extraction is challenging. Non-cyanide extraction of gold is now the focus, and N-bromosuccinimide(NBS) is attracting attention. Herein, new insights into the possible mechanism are deeply revealed through comprehensive analysis and detection of the reaction by using elementary gold and gold bearing ore. Experiments on gold foil indicate that Au can be activated in NBS solution to perform a satisfactory dissolution. Application of NBS in gold extraction from ore show a high yield of 86.24% under optimal conditions of NBS dosage 0.05 M, liquid-solid ratio 4:1, stirring speed 400 rpm, pH 8, 25 °C and leaching for 20 h, while yields of other coexisting metals are nearly negligible. The process leads to direct, efficient, one-pot conversion of gold, into simple water-soluble salts. Characterizations show that the framework of NBS are not destroyed, only bromine separates from the framework. The oxidation of neutral gold atom to trivalent Au (III) occurs in a mild, clean and room-temperature chemistry, which converts gold to [AuBr 4 ] - , and the framework to succinimide. The active bromine and radical Br (Br•) generated from in-situ autocatalysis of NBS are responsible for this. The systematic results herald a green procedure for preparation of gold derivatives and gold extraction industry.
研究领域:
化学工程
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环境科学
✓ 已验证
DOI
PubMed
高影响因子
Journal of Water Process Engineering
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2024
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IF 6.3
Rencong Yang,Xianzhi Hu,Futing Zi,Xinrong Li,Shuliang Chen,Li Zhao,Wanting Li,Yongmao Zeng
Thiosulfate (S 2 O 3 2− )-based gold extraction—an environment-friendly alternative to cyanide-based gold extraction—has notable potential for application in industries. However, resolving the detrimental impacts of arsenopyrite on gold ore leaching remains a challenge for various leaching methods. This study investigated the effects of arsenopyrite oxidation on gold dissolution in a copper(II) (Cu 2+ )–ethylenediamine (en)–S 2 O 3 2− gold-leaching system. During gold leaching, arsenopyrite oxidation considerably influences the properties of the leaching system, thereby increasing the rate of gold dissolution. Moreover, the effects of solution pH, system composition, and dissolved oxygen on gold dissolution were evaluated during the surface oxidation of arsenopyrite. Further, 48 h after arsenopyrite addition, FeOOH and NaAsO 3 were added to the gold foil surface in the leaching system to investigate the effects of excessive arsenopyrite oxidation on gold leaching. Electrochemical tests demonstrate that the surface oxidation of arsenopyrite increases the potential of gold in the leaching system. In addition, X-ray photoelectron spectroscopy results show that the chemical states of arsenopyrite surface elements primarily change from As( I)–S to As(V)–O, Fe(II)–AsS to Fe(III)–AsS, and S 2 2− to S 2− . These results are important for the green hydrometallurgy of refractory gold ores.
研究领域:
冶金学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
MINERALS ENGINEERING
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2023
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IF 4.8
Lei Hou,Alejandro López Valdivieso,Peng Chen,Guowei Zhang,Qi Zhang,Yu Chen,Shaoxian Song,Feifei Jia
Ammonia-free thiosulfate systems are known for their non-toxicity, low reagent consumption, and excellent leaching efficiency in gold extraction studies. This study proposes a novel and environmentally friendly glycine-thiosulfate system and comprehensively investigates the dissolution behavior of gold through the application of electrochemical methods. Electrochemical quartz crystal microbalance (EQCM) has demonstrated that the anodic dissolution of gold is predominantly influenced by the forms of copper(II)-glycine complexes as catalysts, and the presence of Cu(C 2 H 4 NO 2 ) 3 − complex in strong alkaline has enhanced dissolution rate of gold, in contrast to Cu(C 2 H 4 NO 2 ) 2 0 complex in near-nurture condition. Such excellent catalytic capability of the Cu(C 2 H 4 NO 2 ) 3 − complex for gold dissolution can be attributed to the lowest corrosion potential, slighter passivation behavior, and rapid electron transfer from the analysis of corrosion electrochemistry (OCP, PDP, and EIS) and advanced spectrum technologies (LA-ICP-MS and XPS). The dissolution of gold in the novel glycine-thiosulfate system undergoes a typical ligand exchange process (Au + →Au(C 2 H 4 NO 2 ) 2 − →Au(S 2 O 3 ) 2 3− ), and the formation of passivation species on the gold surface is predominantly formed by Au(I)-glycine coordination, rather than the sulfur-containing products from thiosulfate decomposition. Based on these results, the proposed two electrochemical reaction mechanisms will contribute to the optimization of leaching conditions in the novel glycine-thiosulfate system.
研究领域:
冶金学
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电化学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）