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采用钼电极,在973K的温度下,研究了MgCl2在三元NaCl-KCl-CaCl2熔融氯化物混合物中的电化学行为。采用方波伏安法(SWV)、循环伏安法(CV)、计时电流法(CA)和计时电位法(CP)研究Mg2+在钼电极上的反应过程。结果表明,Mg2+在钼电极上发生一步还原反应(Mg2++2e=Mg),是由扩散控制的可逆反应,镁在钼电极上的成核过程是瞬时成核,这与半球核的形成和生长机制是一致的。通过CV、CP和CA在973K的不同方法计算的Mg2+扩散系数分别为1.09×10-5、1.24×10-5和3.23×10-5 cm2/s。在给定电位下阴极沉积产物为金属镁。
Abstract：Electrochemical behavior of MgCl2 in NaCl-KCl-CaCl2 molten chloride mixture was investigated at973 K with inert molybdenum electrode.Electrochemical methods such as square wave voltammetry(SWV),cyclic voltammetry(CV),chronoamperometry(CA)and chronopotentiometry(CP)were used to study reaction of Mg2+on molybdenum electrodes.The results show that Mg2+undergoes one-step reduction reaction(Mg2++2 e=Mg)on molybdenum electrode,which is a reversible reaction controlled by diffusion.Nucleation mechanism of magnesium deposition on molybdenum substrate is instantaneous nucleation,which is consistent with formation and growth mechanism of hemispherical nucleus.The Mg2+diffusion coefficients calculated by different methods of CV,CP and CA in 973 K are 1.09×10-5,1.24×10-5 and 3.23×10-5 cm2/s,respectively.The product deposited by cathode at a given potential is Mg metal.
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基本信息:
中图分类号:TF822
引用信息:
[1]刘兆庭,路贵民,于建国.NaCl-KCl-CaCl_2熔盐体系中Mg~(2+)在Mo电极上的阴极过程[J].有色金属(冶炼部分),2018(12):27-32.
基金信息:
国家自然科学基金资助项目(U1407202)
2018-12-12
2018-12-12