Electrochemical separation of Fe and Ti from ilmenite via molten salt electrolysis and its mechanism

A green separation routes for Fe and Ti from ilmenite via molten salt electrolysis is proposed in CaCl2-NaCl-CaO molten salt. FeTiO3 powder can be dissolved into the molten salt, directly. In the process, CaTiO3 is formed by the reaction of TiO32- and Ca2+ in molten salt components. Pure iron is obtained under the controllable regulation of electrolysis parameters such as cell voltage or electrolysis temperature. Fe is deposited on the cathode by the selective electroreduction of Fe2+ with 2 electrons transfer process. Ti through the consecutive two-steps with 4 electrons transfer electroreduction process of TiO32- is obtained: TiO32- -> TiO -> Ti. FeTi and Fe2Ti alloy is also obtained through reaction of Fe and Ti. The electroreduction of Fe2+ and TiO32- is limited by its diffusion. This approach provides a one-step green and sustainable separation of Fe and Ti from ilmenite (FeTiO3). The main product of Fe and CaTiO3 can be used for the field of catalyst, architecture, aerospace and energy storage materials.