Effect of current density on zinc electrowinning from sulfate solution containing nickel impurity

The effect of current density on zinc electrowinning from sulfate solution containing nickel impurity has been investigated using the mini-cell method under various conditions. With increasing current density from 450 to 750 A/m 2, the average induction time for zinc re-dissolution decreased from 47.19 to 28.65 hours while the average zinc mass prior to the onset of re-dissolution increased from 2.693 to 3.619 g and the average current efficiency (in the electrowinning with a electricity quantity of 3888 C) decreased from 93.74 to 92.93%. Compared with the average cell voltage at 450A/m 2, those at 550, 650, and 750 A/m 2 increased by 2.09%, 2.81%, and 5.52%, respectively. Current density in the range of 450-750 A/m 2 made little difference on cathodic polarization.