Copper recovery in a spouted vessel electrolytic reactor (SBER)

摘要

An investigation of copper recovery from acidic solutions in a particulate, cylindrical spouted vessel of conductive particles is presented. The effects of current, initial copper ion concentration, supporting electrolyte concentration, particle loading, liquid flow rate, solution pH, and temperature on copper recovery rate, current efficiency and energy efficiency of the electrolytic deposition process were investigated under galvanostatic conditions. Experiments were also conducted to investigate the effects of backdissolution or ‘backstripping’ of the deposited metal in the acidic solution. It is hypothesized that the latter occurs via both chemical and electrochemical anodic oxidation in the bed of conductive particles. It was found that sparging of the electrolyte solution with selected gases to remove dissolved oxygen increased the current efficiency by as much as 30 under certain conditions. Finally, a numerical kinetic model of electrochemical deposition and backstripping, coupled with mass transfer in the particulate cathode bed, is presented that describes the behaviour of the net copper recovery curves reasonably well.