Fundamental aspects of calciothermic process to produce titanium

Calciothermic reduction incorporated with electrolytic reclamation of calcium in a single reactor is a new method for extracting titanium from its oxide. Titanium dioxide is typically reduced in molten calcium chloride by calcium existing in this medium as soluble state, not by elemental calcium, to give also soluble calcium oxide and isolated granular sponge titanium to be recovered. This soluble calcium is reproduced simultaneously by electrolyzing the dissolved calcium oxide in the vicinity of the reduction zone of the reactor. In this paper, an outline of this advanced reactor is demonstrated especially from physico-chemical points of view with regard to the following items: (1) Thermochemistry of the CaCl2-CaO-Ca melt, (2) The electrolytic dissolution of calcium into molten calcium chloride. (3) Measure of impurities control, (4) Calciothermic reduction of titanium dioxide in molten calcium chloride.