1990 Volume 106 Issue 4 Pages 181-185
A new-type of lead dioxide electrode was tried as an anode for electrowinning of zinc from sulfate bath in place of the conventional lead alloy electrode which contains about 1% of silver. The new-type electrode gave electrolytic zinc with a lower level of lead contamination, more effective removal of chlorine from electrolyte solution, higher current efficiency, and a higher anodic overpotential than the alloy electrode. Furthermore, the new-type electrode had a high resistance to corrosion and showed relatively low overpotential even at a high cu rrent density without any crust on it.
The use of the new-type electrode may somewhat increase the costs of zinc production compared to the present electrowinning process with an alloy electrode. However, it is believed that the new-type electrode may be more suitable for use in the zinc electrowinning process when the alloy electrode can not be used, e.g., electrowinning of pure zinc which is scarcely contaminated by lead, electrowinning of zinc from a bath with a large amount of chlorine, or electrowinning of zinc at a high current density.
