For zinc hydrometallurgical extraction reducing the electric power consumption of the electrowinning process is an important issue for energy savings. At the Zinc&Lead 2000 symposium, the authors suggested that by using the Pb-0.5%Ag-0.6%Ca alloy, the electrolysis energy can be decreased compared to the conventional Pb-0.9%Ag alloy. In this study, the corrosion behaviors of the Pb-Ag-Ca electrode in a sulfuric-acid electrolyte were investigated. Based on the results for the Pb-0.5%Ag-0.6%Ca anode after 20 days of electrolysis, the bath voltage and the quantity of anode slime decreased compared to the Pb-l%Ag anode. Subsequently, beta-PhO{sub}2 on the electrode surface was detected by XRD and its peaks were sharper than the Pb-l%Ag anode. Moreover, a dense beta-PbO{sub}2 layer on the Pb-0.5%Ag0.6%Ca anode surface was observed. Therefore, it was suggested that the dense beta-PbO{sub}2 layer on the anode surface is one of the factors that leads to a lower bath voltage and decreasing quantity of anode slime.
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