Electrochemical Reduction Behavior of Soluble CaTiO3 in Na3AlF6-AlF3 Melt for the Preparation of Metal Titanium

Direct preparation of metal titanium from soluble CaTiO3 in the Na3AlF6-AlF3 melt by electrolysis was confirmed, providing a short route for the high value utilization of CaTiO3 concentrates obtained from the titanium bearing blast furnace slag. The solubility of CaTiO3 in the Na3AlF6-AlF3 melt at 1253 K was determined by the isothermal saturation method and the electrochemical reduction behavior of TiO32-was investigated by cyclic voltammogram, square wave voltammogram, open circuit potential and potentiostatic electrolysis. The results indicated that the solubility of CaTiO3 in the melt was 2.4% at 1253 K. The TiO32-ions were reduced to metal titanium by the consecutive three-step reduction reactions: TiO32--> TiO -> Ti2O -> Ti. The diffusion coefficient of TiO32-in the Na3AlF6-AlF3 melt was 6.7 x 10-(6) cm(2)s-(1) at 1253 K. The deposited metal titanium was successfully separated with Na3AlF6 by evaporation at 1823 K. (C) 2017 The Electrochemical Society. All rights reserved.