Application of centrifugal fields in fused salt electrowinning with a view to reducing electrolytic energy consumption

A high-temperature, laboratory scale electrochemical cell was designed, constructed, and commissioned to investigate the use of centrifugal fields in fused salt electrolysis production of light metals. Fused salt electrowinning of zinc was initially investigated due to the simpler physical and chemical nature of the Zn_(l)‖ZnCl_2(l):KCl_(l)‖Cl_2(g) system. Current efficiencies of 93 pct were obtained for an electrode spacing of 8 mm using 70-mm-diameter plane disc electrodes rotating at 100 rpm, significantly reducing the resistive contribution to the cell voltage. By reducing the immersion depth of the electrodes from 25 to 10 mm, current efficiencies of 88 pct were obtained for an electrode spacing of only 4 mm for the same operating conditions, further decreasing the resistive contribution to the cell voltage.