Electrochemical extraction of cerium and formation of Al-Ce alloy from CeO2 assisted by AlCl3 in LiCl-KCl melts

Abstract

This work presents an electrochemical extraction of cerium and synthesization of Al-Ce alloy in LiCl-KCl melts on Mo and Al electrodes by chlorination of CeO2 using AlCl3 at 873 K. The cyclic voltammogram on Mo electrodes in LiCl-KCl-CeO2 melt showed no obvious reduction wave other than the reduction of Li(I). After the addition of AlCl3, the signals of the reaction of Ce(III)/Ce(0) and the synthesization of Al-Ce and Al-Li alloys were investigated by cyclic voltammetry, square-wave voltammetry, open-circuit chronopotentiometry and chronopotentiometry. These results indicated that AlCl3 can chloridize CeO2 and that it is possible to extract cerium and form Al-Ce and Al-Li-Ce alloys in LiCl-KCl-CeO2-AlCl3 melts. According to potentiostatic electrolysis, only the Al4Ce layer coated the Al electrodes. According to galvanostatic electrolysis, Al-Ce (Al4Ce, Al3Ce, and Al92Ce8), Al2Li3, and Al phases were formed on Mo electrodes, and the content of cerium in the Al-Li-Ce alloys was more than 17 wt%.