Solvometallurgical process for extraction of copper from chalcopyrite and other sulfidic ore minerals

Abstract

Extraction of copper from sufidic ores, either by pyrometallurgy or hydrometallurgy, has various limitations. In this study, a solvometallurgical process for the extraction of copper from sulfidic ore minerals (chalcopyrite, bornite, chalcocite and digenite) was developed by using an organic lixiviant (FeCl 3 as oxidizing agent and ethylene glycol (EG) as organic solvent). All the studied copper sulfide minerals could be leached efficiently with a FeCl 3 -EG solution. Other lixiviant systems, namely CuCl 2 -EG, FeCl 3 -ethanol and FeCl 3 -propylene glycol could also extract copper, but they did not perform as well as the FeCl 3 -EG solutions. The mechanistic study of chalcopyrite leaching in FeCl 3 -EG solutions confirmed that the leaching products of chalcopyrite were FeCl 2 , CuCl and solid elemental sulfur, where the Fe(II) and Cu(I) were quantified by UV-Vis absorption spectroscopy and solid sulfur was identified by powder XRD. A kinetic study showed that the leaching process was a surface chemical controlled process and the apparent activation energy was calculated to be 60.1 kJ mol −1 . Subsequently, electrodeposition of copper from the pregnant leachate was investigated, and SEM-EDX analysis showed that uniform cubic crystalline deposits of pure copper were produced. Meanwhile, the Fe(III) was regenerated by oxidizing Fe(II) at the anode, with a Morgane membrane in between two electrode compartments to prevent the transfer of Fe(III) to the cathode. Finally, a closed-loop solvometallurgical process was designed with three operational steps: leaching, electrodeposition and removal of Fe(II). The regeneration of the FeCl 3 -EG solution and the use of EG contribute to the sustainability and the greenness of the process.

Solvometallurgical Recovery of Platinum Group Metals from Spent Automotive Catalysts

“…The concentration of Fe(II) in the leachates was quantified using an Agilent Cary 6000i UV−vis−NIR spectrometer with 1,10-phenanthroline as a colorimetric agent. 19 The samples were prepared by mixing a certain volume of the leachate with 1 mL of 1,10phenanthroline solution (0.5 wt % in CH 3 CN) and 1 mL of buffer solution (1: 1 v/v of 5 mol L −1 NaOH and 6 mol L −1 CH 3 COOH, pH = 3.5). The mixture was then diluted with milliQ water to 10 mL.…”

“…, uranium, rhenium, zirconium, and copper) in organic solvents ( i.e. , bromide–ethyl acetate, bromide–methanol, chlorine–FeCl 3 –dimethylformamide, and FeCl 3 –ethylene glycol). − Recent work of our research group showed that different metals can be dissolved in trihalide ionic liquids, with the trichloride compounds as the most reactive ones. , Nakao et al studied the dissolution of noble metals using elemental halogens and halides dissolved in polar organic solvents . The quantitative recovery of palladium from spent catalytic converters can also be achieved using N , N′ -dimethylperhydrodiazepine-2,3-dithione diiodine .…”

Solvometallurgical recovery of cobalt from lithium-ion battery cathode materials using deep-eutectic solvents

“…28 Solvometallurgical routes produce less aqueous waste and are often more selective than hydrometallurgical processes. [28][29][30][31] Often used green solvents in solvometallurgy are deep-eutectic solvents (DESs). [32][33][34] DESs are low-melting mixtures with a melting point much lower than those of its individual components.…”

Mechanism of selective gold extraction from multi-metal chloride solutions by electrodeposition-redox replacement

“…[25][26][27] In addition, DESs enable precious metals to be oxidized at lower overpotentials, 28 and are thus preferred in leaching applications. [29][30][31][32] In this paper, the effects of solvent's physicochemical properties, such as metal speciation and mass transport, on the efficiency of the EDRR method were investigated in aqueous chloride solution and in deep eutectic mixture of choline chloride with ethylene glycol in 1 : 2 molar ratio (1 : 2 ChCl : EG). Moreover, the concentration of chloride ions in this DES is ca.…”