Electrochemical deposition of Nd and Nd–Fe alloy from Cu₆Nd alloy in a NaCl–KCl–NdCl₃ melt

Abstract

Electrorefining effectively separates metals from their corresponding alloys. To obtain Nd from Cu₆Nd alloy, cyclic voltammetry and square wave voltammetry were used to investigate the reduction behavior of Nd³⁺ and the anode dissolution behavior of Cu₆Nd in the NaCl–KCl–0.5mol%NdCl₃ melt at 1023 K. According to the analysis of the electrochemical behavior, the cell voltage was determined to be between 0.3 and 1.2 V for separating Nd from Cu₆Nd. After electrolysis at 0.6 V for 4 h, the Nd was found at the surface of the Mo cathode without any Cu. For the Fe cathode, a deposition with an atom ratio of Nd: Fe = 1:1 was formed on the surface. However, the low current density of separation remains a great experimental challenge that must be solved.

Keywords

Cu₆Nd alloy / molten salt / electrochemical separation / NaCl–KCl–NdCl₃

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