有色金属电积用pb-gd阳极性能研究 - 有色金属（冶炼部分）.doc

铜在LiCl-KCl熔盐中的电化学行为研究 蔡艳青1，刘红霞1，许茜2，宋秋实1，徐亮1 (1.东北大学 材料与冶金学院沈阳 110004；2.上海大学 材料科学与工程学院，上海 200072) 摘要：采用循环伏安方波伏安计时电位及线性扫描伏安法研究了500 ℃时Cu(I)在LiCl-KCl熔盐体系中石墨电极和钼电极上的电化学行为并且研究了不同CuCl浓度下铜的沉积电位。结果显示铜离子在熔盐中的还原过程分两步进行，分别在-1.05 和-1.55 V处依次还原，即Cu(II)→Cu(I)和Cu(I)→Cu(0)。通过循环伏安及计时电位测试，均得出Cu(I)在LiCl-KCl熔盐中的阴极还原过程为受扩散控制的准可逆过程，扩散系数分别为1.79×10-5 cm2s和1.26×10-5 cm2s。 关键词：氯化物熔盐铜电化学测试扩散系数 中图分类号：TF811；TG146.1+1 文献标志码：A 文章编号：1007-7545（2015）-0000-00 Electrochemical Behavior of Copper in Eutectic LiCl-KCl Melt CAI Yan-qing1, LIU Hong-xia1, XU Qian2, SONG Qiu-shi1, XU Liang1 (1. School of Material Science and Metallurgy, Northeastern University, Shenyang 110004, China; 2. School of Materials Science and Engineering, Shanghai University, Shanghai 200072, China) Abstract: The electrochemical behavior of Cu(I) in eutectic LiCl-KCl (58.5︰41.5 mol ratio) melt was investigated on graphite and Mo electrodes at 500 ℃ by cyclic voltammetry, square wave voltammetry, chronopotentiometry, and linear sweep voltammetry. The cathodic peak currents and initial deposition potentials of copper under different concentrations of CuCl were obtained. The results show that two initial reduction potentials of copper ions are obtained at -1.05 V and -1.55 V on graphite electrode, which correspond to Cu(II)/Cu(I), and Cu(I)/Cu(0) couples, respectively. Reduction of Cu(I) is a quasi-reversible process controlled by diffusion mass transfer. The diffusion coefficients of Cu(I), calculated by the results of cyclic voltammetry and chronopotentiometry, is 1.79×10-5 cm2/s and 1.26×10-5 cm2/s, respectively. Key words: molten chlorides, copper, electrochemical test, diffusion coefficient 目前主要在水溶液[1-3]及离子液体[4]中铜离子的电化学行为动力学参数电解精炼，而熔盐中铜的电化学行为则研究相对较少。Lantelme等[5]研究了Cu(I)在LiCl-KCl熔体中氧化为Cu(II)过程的扩散系数及Cu(I)还原过程晶体生长情况，并通过计时电位法及原子示踪法研究了Cu(I)在LiCl-KCl熔体中的扩散系数[6]。Anders等[7]研究了Cu(I)及Cu(II)在AlCl3-NaCl-KCl熔盐中的平衡电位。Castrillejo等[8]研究了Cu(II)/Cu(I)及Cu(I)/Cu(0)电对在ZnCl2-2NaCl中的电化学行为，并得出了Cu(II)/Cu(I)及Cu(I)/Cu(0)的标准电极电位及电化学反应动力学常数。Proskurnev等[9]研