Anode Process on Platinum in Low Temperature KF-AlF₃-Al₂O₃ Based Melts: An Update

Abstract

The present paper is devoted to obtaining new fundamental data on the electrochemical behavior of oxygen-evolving anodes in fluoride-oxide melts. In this work, the function of platinum and basics of its anode behavior as an ideal oxygen-releasing anode during electrolysis of the low-temperature KF-AlF3-Al2O3-based melt were studied by potentiometric, cyclic voltammetric, and chronopotentiometric methods. The influence of the electrolyte composition, temperature, atmosphere, potential sweep rate, current density on the kinetics of the anode process was investigated. In order to clarify the mechanism of the process under study, electrolysis testing was carried out to inform an analysis of platinum oxidation products. Based on the experimental results, the validity of an earlier proposed scheme of the anode process on platinum when carrying out electrolysis of low temperature KF-AlF3-Al2O3 based melts was confirmed. Results will be used for theoretical modeling and studying the kinetics of the anode process on an over oxygen-evolving anodes in the fluoride-oxide melts.