The results of investigations of the electrochemical behaviour of multicomponent lead-tin alloys under cathodic polarization in a sodium hydroxide melt are presented. It has been shown that as a result of the formation of intermetallic compounds, such elements as antimony, tin, bismuth and arsenic are extracted from the cathode to the anode. The electrolysis product on the cathode is lead with a total percentage of the above impurities of 0.065-0.070%. The extraction kinetics have been studied, the dissolution rate constants for each of the alloy components have been determined and a mechanism of mass exchange between the electrodes has been proposed. The current consumption for the extraction of metals from the melt has been determined.