Acta Phys. -Chim. Sin. ›› 2014, Vol. 30 ›› Issue (9): 1674-1680.doi: 10.3866/PKU.WHXB201407022

• ELECTROCHEMISTRY AND NEW ENERGY • Previous Articles     Next Articles

Electrochemical Co-Reduction Extraction of Neodymium in LiCl-KCl-ZnCl2 Molten Salt System

XUE Yun1,2, ZHOU Zhi-Ping1, YAN Yong-De1,2, ZHANG Mi-Lin1, LI Xing1, JI De-Bin1, HAN Wei1, ZHANG Meng2   

  1. 1. Key Laboratory of Superlight Materials and Surface Technology, Ministry of Education, College of Materials Science and Chemical Engineering, Harbin Engineering University, Harbin 150001, P. R. China;
    2. Fundamental Science on Nuclear Safety and Simulation Technology Laboratory, Harbin Engineering University, Harbin 150001, P. R. China
  • Received:2014-05-22 Revised:2014-07-02 Published:2014-08-29
  • Contact: YAN Yong-De E-mail:y5d2006@hrbeu.edu.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (21103033, 21101040, 91226201, 51104050), Special Foundation of China and Heilongjiang Postdoctoral Science Foundation, China (2013T60344, LBH-TZ0411), Fundamental Research Funds for the Central Universities, China (HEUCF141502), and Foundation for University Key Teacher of Heilongjiang Province and Harbin Engineering University, China (1253G016, HEUCFQ1415).

Abstract:

This work focused on the electrochemical behavior of Nd(Ⅲ) and the formation of Zn-Nd alloys on Mo electrodes in LiCl-KCl-ZnCl2 molten salt system at 773 K. Cyclic voltammetry, open-circuit chronopotentiometry, and square-wave voltammetry were used. The results showed that the underpotential deposition of Nd on a predeposited Zn cathode gave three types of Zn-Nd intermetallic compounds in LiCl-KCl-ZnCl2 solutions. Based on the electrochemical results, square-wave voltammetry was used to determine the concentration changes of Nd during potentiostatic electrolysis. The extraction efficiency of Nd was evaluated based on the concentration changes after electrolysis. The results indicated that the concentration of Nd(Ⅲ) was close to zero, and the extraction efficiency was 99.67% after potentiostatic electrolysis at -1.84 V for 50 h. The extraction of Nd and preparation of Zn-Nd alloys were performed by galvanostatic electrolysis at 973 K. The phase compositions and microstructures of the alloys were analyzed using X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS). XRD showed that Nd2Zn17, LiZn, and Zn phases were present in the alloys. The EDS results indicated that the concentration of Nd in the alloys reached 14.99%.

Key words: LiCl-KCl molten salt, Electrolysis in molten salt, Electrochemical extraction, Zn-Nd alloy, Extraction efficiency

MSC2000: 

  • O646