Feasibility Study of Sungun Chalcopyrite ConcentrateElectro and Chemical Leaching in Choline Chloride-Urea-Maleic Acid Deep Eutectic Solvent

In this research, the feasibility of chemical and electrical dissolution (electro-leaching) of Sunguncopper concentrate in deep eutectic solvent (DES) based on choline chloride (ChCl), Urea and maleicacid (MA) with different molar ratios was investigated. In electro-leaching experiments, graphitecathode was used. Different methods including pressed electrode, carbon paste electrode, and rodgraphite with chalcopyrite powder added in DES were applied to create anodes. Also, chalcopyriteconcentrate chemical leaching experiments were performed with two-component (including ChCl:Ureaand ChCl:MA) and three-component (including ChCl:MA:Urea) DESs. The concentration of Cu forthe pressed electrode, carbon paste electrode, and chalcopyrite powder added in DES was obtained as۳.۷, ۷.۶, and ۳.۹ ppm, respectively, and the copper recovery for three tests were obtained ۰.۲۳, ۰.۳۸,and ۰.۴۸%, respectively. The obtained result confirmed that chalcopyrite is not dissolved through theelectro-leaching process under these conditions. Therefore, it can be claimed that the chalcopyriteelectro-leaching process cannot be performed in an anodic state. Next, binary and ternary compoundsof DES were used to dissolve copper. The results showed that the concentration of copper in twocomponentsolvents ۲ChCl:۱Urea is equal to ۳.۸ ppm and in ۱ChCl:۲Urea ۳.۹ ppm at ۲.۵ h, ۲۲.۹ ppmat ۴ h and ۳۰.۸ ppm at ۲۴ h, which indicates the dissolution efficiency below ۲% for all experiments.Using ChCl:MA with a molar ratio of ۱:۱, the copper concentration was ۴۴۰.۱, ۱۰۰۷.۵, and ۱۴۱۶.۸ ppmat ۱۰۰, ۱۵۰, and ۲۰۰ °C for ۴ h leaching, respectively. In three-component solvents, copperconcentration in ChCl:MA:Urea (۱:۱:۱) was equal to ۷.۳۴, ۷.۶۶, ۱۲.۹۴, and ۱۶.۸ ppm for differentconditions. Therefore, copper recovery for ChCl:MA:Urea was lesser than ۱ % for all experiments internary DES. The addition of urea causes a sharp drop in efficiency and the lack of dissolutionof copper contained in chalcopyrite in DES. Then, the best copper dissolution efficiency wasobtained ۴۸ % in DES with the combination of ChCl and MA.