Anodic behaviour of the Pb-Co3O4 composite coating in copper electrowinning

The electrochemical and corrosion properties of Fb-Co3O4 (about 3% Co) comp osite anode for copper electrowinning without additives as well as in the p resence of two combinations of organic additives in the electrolyte have be en investigated and compared with those of Pb-Sb 5.85% anode. The formation of PbO2 layer on the surface of these electrodes was traced by cyclic volt ametric measurements using rotating disc electrode (RDE) method. The Pb-Co3 O4 composite anode shows a depolarizing effect on the process of oxygen evo lution as compared to Pb-Sb anode. The corrosion rate of Pb-Co3O4 anode dur ing prolonged polarization is approximately 6.7 times lower than that of Pb -Sb anode. The influence of the rested organic additives on the anodic beha viour of both anodes is negligible. (C) 2001 Elsevier Science B.V. All righ ts reserved.