Voltammetric Evaluation of Zinc Electrowinning Solution Containing Nickel

Abstract

The effect of nickel impurity in zinc sulfate electrowinning solutions was studied using voltammetry techniques. The reactions occurring at various points on the polarization curve are proposed and comparisons made for both pure electrolyte and those containing nickel. A nickel‐activated hydrogen evolution peak was found to occur at low current densities during the anodic sweep portion of the curve, the height of which was found to be proportional to the nickel concentration in solution. The influence of certain operating parameters such as zinc ion concentration, potential scan limit, and scan rate on the nickel activated peak was also determined.