Reaction mechanism of preparation of titanium by electro-deoxidation in molten salt

The electro-deoxidation of TiO2 was investigated in molten CaCl2. Back electromotive force measurements, constant voltage electrolytic experiments, contrast experiments of different cathodes, and cyclic voltammograms were carried out for solving the puzzle of reduction mechanism. The results showed that the reduction process proceeded step by step. TiO2 was first reduced to Ti3O5 or Ti2O3, and then further reduced to Ti3O, Ti2O, TiO and Ti. In addition, direct electrochemical reduction of titanium dioxide was the primary cathodic reaction; meanwhile, some calciothermic reduction reactions also happened at the cathode. Cyclic voltammograms of solid titanium dioxide and molybdenum wire in molten salts with different compositions were also studied.