Low temperature electrodeposition of titanium in fluoride-added LiClKClCsCl molten salt

Abstract

We investigated electroreduction of Ti2+ to metallic titanium in the LiClKClCsCl system, which has a eutectic point at 263 °C. Cyclic voltammetry was carried out in the TiCl2-saturated LiClKClCsCl at 300 °C, and the effect of F1 addition on the reduction behavior of Ti2+ was investigated. It was revealed that addition of F1 increases the limiting current density of electrodeposition of titanium at 300500 °C. This might be mainly attributed to the increase in total concentration of soluble titanium ions in the molten salt. Then, we demonstrated the electrodeposition of metallic titanium in the LiClKClCsCl with and without F1 at 350 °C. After the electrolysis in F1-added molten salt and acid leaching, LiF remained on the deposited titanium. This is because the solubility of LiF in aqueous solution is quite low. An efficient method to remove LiF is required when F1-added LiClKClCsCl is used as electrolyte.