Abstract
Cathodic reduction of Ti ions and anodic oxidation of Cl ion were investigated in LiCl-KCl eutectic melt. The experiments were carried out under argon atmosphere at higher temperature than 500°C with addition of TiCl3 and/or Ti chips. The results are summarised as follows.
Two waves on linear sweep voltammograms were observed when TiCl3 was added to the melt. The first reduction wave appears at the potential near-0.6V, and is attributed to the step of Ti3+ → Ti2+. The second reduction wave appears at-1.1V corresponding to the step of Ti2+ → Ti0. Reduction rate of Ti2+ → Ti0 was proportional to concentration of Ti2+. The reduction potentials at which Ti3+ → Ti2+ and Ti2+ → Ti0 reductions take place are in good agreement with the theoretical ones calculated from the thermodynamic data. The oxidation of Cl- → Cl0 takes place at + 1.0V which corresponds well to the theoretical oxidation potential. Electrodeposit at-1.2V in the melt containing Ti2+ was found to be titanium metal, by EPMA analysis.
