A new reduction process is presented where TiO_2 is used as the raw material for reduction. It consists of the calcium reduction in the molten CaCl_2 bath and the electrochemical reaction for recovery of Ca from CaO in the same bath. TiO_2 powder injected near the cathode reacts with a few mol%Ca dissolved in the melt. The by-product CaO of calciothermic reduction dissolves into the molten CaCl_2, and it is electrochemically decomposed into Ca and CO/CO_2 gas by giving the voltage higher than that of theoretical decomposition for pure CaO. Some experimental results confirmed this process proposal, and the sufficiently deoxidized titanium metal was obtained at the bottom of the cell, when the basket type cathode was applied. Because the molten CaCl_2 has a large solubility for CaO, both mechanisms of the halide flux deoxidation and the electrochemical deoxidation worked efficiently to remove oxygen in Ti, once the metallic Ti particles were precipitated. This mechanism based on the calciothermic reduction and the electrolysis of CaO was experimentally approved in comparison with FFC process.
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