Separation of metallic Ti from Cu-Ti alloys through a simple and efficient electrochemical approach

Abstract

Owing to the enhanced selective depolarization effect of the liquid Cu, Ti has been successfully collected from mixed oxide ores or slags by using advanced molten oxide electrolysis (MOE) configuring with a liquid Cu cathode. However, the products prepared via above process are Cu-Ti alloys. Additional process is needed for the separation of Ti from those alloys. To achieve this goal, here, we selected a simple electrochemical approach to separate Ti from the Cu-Ti alloys in molten salt. Compared to the pure Cu electrode, the Cu-Ti alloys with different Ti contents show more negative electro-oxidation potential, which, in principle, indicates that Ti could be electrochemically extracted from the Cu-Ti alloys. Furthermore, the results of constant current electrolysis show that the effective separation of Ti is affected by the anodic current density and the Ti content in the Cu-Ti alloys. Specifically, the anodic current density, enabling the effective separation of Ti, increases with the increase of the Ti content in the Cu-Ti alloys. We have fitted a relationship equation between the anodic current density and the Ti content, which will be helpful for guiding separation of Ti from the Cu-Ti alloys. These findings confirm the feasibility of the molten salt electrolysis for the separation of Ti, and also make the Ti extraction based on the advanced MOE a complete process.