The effects of Al~(3+) and CR~(3+) on nickel electrowinning from sulfate electrolyte

摘要

The effects of the impurities Al~(3+) and Cr~(3+) on the physical appearance, surface morphology and current efficiency of nickel deposited from sulfate electrolytes were determined. The current efficiency decreased in the presence of these impurities over the concentration range studied, the maximum being 40 mg/l. Changes in the surface morphology, internal stress and polarization behavior were also observed as the impurity concentration increased. Based on the physical appearance of the electrodeposited nickel, the tolerance limits of the impurities in the electrolyte are reported. The influence of the initial stainless steel cathode surface on nickel quality and general electrochemical characteristics of the pure and impure systems were also determined.