Effect of impurities in recycling water on Pb-Ag anode passivation in
zinc electrowinning process
zinc electrowinning process
(1. School of Metallurgical Science and Engineering, Central South University, Changsha 410083 China;
2. Changtian International Engineering Corporation, MCC, Changsha 410008, China)
2. Changtian International Engineering Corporation, MCC, Changsha 410008, China)
Abstract: Effect of impurities in recycling water on Pb-Ag anode passivation in zinc electrowinning process was investigated by linear scan voltammetry. Results show that passivation process would be affected in the presence of Cl− and F− in recycling water. It was highly advantageous to take H2SO4 concentration as 180 g/L, Mn2+ concentration as 3−5 g/L and F− less than 42 mg/L. However, passivation process would not be affected when Cl− concentration was less than 13 mg/L without any other ions, or when mass ratio of Mn2+ to Cl− existing in electrolyte was 8, where Cl− concentration could reach up to 625 mg/L.
Key words: zinc electrowinning process; Pb-Ag anode; passivation; impurities; recycling water