Electrochemical Extraction of Cerium by Forming Ce-Zn Alloys in LiCl-KCl Eutectic on W and Liquid Zn Electrodes

Abstract

© The Author(s) 2015. Published by ECS. The electrochemical formation of Ce-Zn alloys in LiCl-KCl eutectic was systematically investigated by cyclic voltammetry (CV), square wave voltammetry (SWV) and open circuit chronopotentiometry (OCP). Due to the decrease of Ce activity in the metal phase of formed Ce-Zn alloys, the deposition potential of Ce(III) at a liquid Zn electrode was found to be 0.64 V more positive than that on an inert W electrode. The co-reduction behaviors of Ce(III) and Zn(II) ions were also studied in LiCl-KCl eutectic. Signals associated with six and nine Ce x Zn y intermetallic compounds were detected by CV and OCP techniques, respectively. In addition, potentiostatic electrolyses were carried out to extract Ce at a liquid Zn electrode in LiCl-KCl-CeCl 3 melt and on a W electrode in LiCl-KCl-CeCl 3 -ZnCl 2 melt, respectively. Deposited samples were analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy (EDS). The results showed that intermetallic compound CeZn 11 was prepared on both the inert W electrode and liquid Zn electrode.