Extracting of copper from simulated leaching solution of copper-cadmium residues by cyclone electrowinning technology

Cyclone electrowinning technology has obvious technical advantages in treating polymetallic mixed solutions, and it has been widely used to separate and purify cu, au, ag, Ni, co and other metals. Simulated leaching solution of copper‑cadmium residues was prepared as electrolyte, the extraction of copper by three-stage cyclone electrowinning in sequence were investigated in this study, and the optimum conditions of each stage were determined. In the first stage, the purity of cathode copper can reach over 99.996%, and the current efficiency can reach to 98.75% when the current density was 300A/m2 and the electrolyte circulation flow was 400 L/h. in the second stage, the purity of cathode copper can achieve the standard of the cathode copper(>99.99%)，and the current efficiency can reach to 98.93% when the conditions are determined as the current density of 400A/m2 and the circulation flow of 700 L/h. in the third stage, the cathode copper with over 99.9% purity can be obtained and the current efficiency can reach to 93.37% when the current density was 200A/m2 and the circulation flow was 500 L/h. the concentration of copper ions in the electrolyte can be reduced to below 0.1 g/L and the removal efficiency of copper can reach over 99% in the study. Compared to the traditional electrowinning process，the cyclone electrowinning shows the advantages of high metals selectivity，high current efficiency, high purity of electrolytic products and low environmental pollution, which has good economic and social environmental benefits •Copper extraction from polymetallic mixed solutions by cyclone electrowinning.•Ion concentration is more affected by current density than circulation flow.•Circulation flow does not affect the ion decline rate, but improves mass transfer.•Current efficiency and cathode copper purity decrease with the electrodeposition process.•Cyclone electrowinning has more advantages than traditional electrowinning.