Acta Phys. -Chim. Sin. ›› 2015, Vol. 31 ›› Issue (5): 920-926.doi: 10.3866/PKU.WHXB201503251

• ELECTROCHEMISTRY AND NEW ENERGY • Previous Articles     Next Articles

Electrochemical Behavior and Extraction Efficiency Evaluation of Gd in Chloride Molten Salt System

YANG Xiao-Nan1, YAN Yong-De1,2, ZHANG Mi-Lin1, LI Xing1, XUE Yun2, HAN Wei1   

  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:2014-12-18 Revised:2015-03-24 Published:2015-05-08
  • 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 (HEUCF20151007), and Foundation for University Key Teacher of Heilongjiang Province and Harbin Engineering University, China (1253G016, HEUCFQ1415).

Abstract:

The electrochemical behavior and thermodynamic properties of GdCl3 in LiCl-KCl molten salt system on both Mo and Al electrodes at 773 K were investigated. An open circuit chronopotentiogram was used to determine the equilibrium potentials and standard apparent potentials of the Gd(III)/Gd(0) system in the temperature range 723-873 K. The results showed that the equilibrium potentials and apparent standard potentials became positive with increasing temperature. The activity coefficients of GdCl3 were calculated at different temperatures. The depolarization values were calculated by steady state polarization tests, and the theoretical extraction efficiency was obtained at 773 K. Potentiostatic electrolysis was performed to extract gadolinium from LiCl-KCl-GdCl3 molten salt on Al electrodes at -1.5 V. The extraction efficiency was about 94.22% after 20 h. The Al3Gd phase was identified in the deposit by X-ray diffraction (XRD).

Key words: Molten salt, Change of gibbs free energy, Activation coefficient, Extraction efficiency, Electrolytic extraction

MSC2000: 

  • O646