Bipolar electrolyzer for black lead refining

New electrolyzer construction for electrolytic refining of black lead from technogenic and secondary materials has been developed.

Processed materials:

  • non-ferrous metallurgy solid wastes (grind, cake, copper,  zinc and lead production mattes);
  • secondary raw materials –  waste lead-acid batteries.

Electric refining being performed in molten salts results in formation of grade lead as a ready product at the cathode and lead ligature at the anode: lead-stibium and lead-bismuth with definite stibium and bismuth concentrations containing metal impurities.

Bipolar electrolyzer includes: frame made of heat resistant concrete, liquid metal anode and cathode, bipolar electrode, non-porous electroconductive diaphragm which divides space between anode and cathode. Electric scheme of the device allows setting the temperature in the range of 500-600 °С and the constant current intensity 300-1000 А.  The electrolyzer construction provides continuous electrorefining operation (black lead loading and cathode metal uploading).

The bipolar electrolyzer with a current load of 500 and 1000 A  was successfully tested in semi-industrial conditions. The C1 grade lead test benches (GOST 3778-98 lad content not less than 99,985  wt.%) and lead ligatures were obtained.


  • Electrolyzer construction allows producing in a single operation pure metal which meets the world standards requirements related to controlled impurities concentration.
  • High durability material for electrolyzer frame construction was proposed.
  • Refining process efficiency increases due to the cathode current density rise.
  • Electrolyzer operation reliability increases due to novel technological and construction concepts.
  • Suggested construction can be used to design  devices for  large tonnage production.