Effect of Zn2+ on the extraction of copper by cyclone electrowinning from simulated copper-containing electrolyte

Abstract

• The effect of Zn 2+ on the recovery of cyclonic electrodeposited copper was studied. • The activity of Zn 2+ is considered in this paper. • Experimental data were measured by intermittent in situ sampling. • The reasons affecting the deposition quality are analyzed from the aspects of flow state, diffusion and polarization. • Synergistic effect of ion concentration and mass transfer rate on surface morphology of deposited copper. Cyclone electrodeposition has obvious advantages in the treatment of composite metal electrolyte. The effect of impurity metal ions on electrodeposition of copper by cyclone electrodeposition was investigated. Different concentrations of Zn 2+ in copper electrolyte have different effects on electrodeposition. The current efficiency of cyclone electrodeposition with different concentrations of Zn 2+ and the concentration of Cu 2+ and Zn 2+ in copper electrolyte at different deposition times were measured. The purity and morphology of cathode copper obtained by electrodeposition were determined. The results show that the higher the addition of Zn 2+ , the higher the concentration of Cu 2+ at the terminal point, the lower the removal rate of Cu 2+ in the electrolyte and the lower the current efficiency of the cyclone electrodeposition process. With the increase of the amount of Zn 2+ , the dendrite morphology of cathode copper gradually forms after the three-stage electrodeposition. With the progress of the electrodeposition process and the increase of the amount of Zn 2+ , more and more dendrites will be produced on cathode copper. Therefore, when the composite copper electrolyte (such as copper electrolyte or copper waste liquid) is purified by cyclone electrodeposition, the content of Zn 2+ in the composite copper electrolyte should be controlled below 3 g /L to obtain cathode copper products with good quality and good morphology.