Electrochemical Behaviors of Consumable Ti2CO@Al2O3 Anode for Ti Extraction by USTB Process

Abstract

USTB technology is widely considered as a low-cost and environmentally-friendly method for titanium extraction from a consumable TiCxOy anode. It is expected to directly prepare TiCxOy by selective carbothermal reduction of titanium ores, not pure TiO2. However, impurities in titanium ores, particularly Al2O3, may affect the electrochemical dissolution of TiCxOy and Ti extraction. In this work, the effects of Al2O3 impurity on the preparation and dissolution behaviors of Ti2CO are studied. It is found that the existence form of Al2O3 is not changed during carbothermal reduction. With the increase of Al2O3 content, the conductivity of Ti2CO anode slightly decreases from 143.1 to 131.6 S cm−1 and the anodic polarization curves of Ti2CO@Al2O3 shifts to the positive direction due to the increase of dissolution resistances. Al2O3 in Ti2CO@Al2O3 anode will drop into molten salts to form anode slime during USTB process. On both liquid Zn and solid nickel cathodes, Ti is electrodeposited, which is not affected by Al2O3 impurity. Therefore, it is confirmed that typical Al2O3 impurity has no obvious effect on the electrochemical dissolution of Ti2CO anode and Ti extraction. The advanced USTB process is expectedly developed by the selective carbothermal reduction of titanium ores to prepare Ti2CO anode.