FLUIDIZED-BED ELECTROWINNING OF ZINC FROM CHLORIDE ELECTROLYTES

A laboratory cell was operated at superficial current densities in the range 1200-7500 A/m**2 with catholytes containing up to 62 kg/m**3 Zn and 28 kg/m**3 HCl. Anolytes examined contained 58 kg/m**3 NaCl and up to 100 kg/m**3 HCl and, in some instances, had the same composition as the catholyte. Both pure catholytes and ones with deliberate additions of impurities (Ni, Co and Sb) were used. Pure solutions yielded current efficiencies and power consumptions comparable to or better than those of cells with conventional electrodes. Antimony (particularly in combination with Ni and Co) had a detrimental effect on cell performance; this was alleviated by simultaneous additions of glue.