ELECTROCHEMICAL-BEHAVIOR OF TITANIUM IONS IN THE CSCL-KCL-NACL-NAF-K2TIF6 MELT

Linear voltammetry, potentiostatic electrolysis, and steady-state curr ent-potential curves recorded in the CsCl-KCl-NaCl-NaF (10 wt %)-K2TiF 6 melt before and after its interaction with titanium metal in the tem perature range 847-1045 K have been employed to establish that the red uction of Ti(IV) to Ti(0) occurs through two consecutive stages involv ing transfer of one and three electrons, respectively. The voltammogra m shape and its parameters for the first reversible stage do not depen d on the material of the working electrode, while the second stage is reversible on the platinum and irreversible on the glassy-carbon and t itanium electrodes. The diffusion coefficients determined with the aid of the platinum working electrode are found to be equal to (0.50 - 1. 51) x 10(-5) and (1.14 - 1.83) x 10(-5) cm(2)s(-1) for Ti(IV) and Ti(I II), respectively; the activation energy of diffusion is equal to 42.1 and 21.3 kJ mol(-1), respectively.