EFFECT OF IRON ON ENERGY CONSUMPTION AND CURRENT EFFICIENCY OF ZINC ELECTROWINNING FROM SULFATE SOLUTIONS

Abstract

Electrolytic zinc used in galvanizing processes is obtained using zinc electrowinning from sulfate solutions. The presence of impurities in the electrolyte is a major problem for the zinc electrowinning industry. The impurities on zinc electrolysis can reduce the current efficiency and increase the energy consumption. In this work, the effect of iron on the zinc electrodeposition using galvanostatic deposition and cyclic voltammetry is studied. Contents of 5, 10, and 15 mg.L-1 of iron were added in the electrolyte of zinc sulfate and in an industrial acid electrolyte. Using the industrial electrolyte, iron addition is detrimental to the zinc electrowinning, increasing the energy consumption and decreasing the current efficiency.