Factors affecting the electrochemical behaviour of copper anodes under simulated electrorefining conditions

Abstract

Cyclic voltammetry (CV) was used to characterize the behaviour of copper anodes during electrorefining. The method involved cycling the anode potential at a rate of 2 mV s⁻¹ between the open circuit potential of −0.35 V and 0.0 V vs mercury/mercurous sulphate (MSE) reference electrode. Reproducible electrochemical characteristics for pure copper anodes of different shapes, sizes and configurations (vertical vs horizontal) were determined. Passivation time measurements indicated a strong correlation between the CV profile and the ease of anode passivation. The size, shape and geometrical configuration of the anode impact significantly on the electrochemical dissolution and passivation of pure copper. An IBM compatible computer equipped with a data acquisition board was used to acquire, examine, compare, and catalogue the electrochemical data which were presented in the form of a potential-current-time spectrum rather than a conventional cyclic voltammogram. This format enhanced the clarity and readability of the results.