On the lead smelting by means of a fused salts electrolysis

Abstract

Metal sulphides may be smelted electrolytically by dissolving in fused metal chlorides like alumina in cryolite bath. In this paper a method is discussed, in which galena dissolved in amount of 5-13% in fused lead choride at about.500°C is electrolizeil with the cathodic current densities of 2-3 A/cm-2., 2-4 volts of the terminal drops and 90% or more of the current efficienices.
Impurities in the galena are classified into two groups, sulphides of Ag. Bi. Sb. As. and thosa of Cu. Fe. Zn; the former deposit preferentially and make the deposited lead impure, the latter disturb the electrolysis owing to accumulation in the bath. Iron sulphide forms complex sulphide with galena in the bath and then electroly tically deposits as iron disulphide crystals on the anode.