(江西理工大学 冶金与化学工程学院，赣州 341000)
摘 要: 采用循环伏安法、计时电流法、计时电位法研究以MgO为原料、LiF-MgF2-BaF2-KCl为电解质体系、温度为1173 K时镁离子在钨电极上的电化学还原过程。结果表明：镁离子在钨电极上的电化学还原是一步转移两个电子的过程，电极反应为Mg2++2e→Mg；镁在钨电极析出过程中出现成核极化现象，析出过程是受扩散控制的不可逆反应；1173 K时，Mg2+在熔盐中的扩散系数D为1.28×10-5 cm2/s。
关键字: 氧化镁；熔盐；电化学还原；扩散控制
（School of Metallurgical and Chemical Engineering,
Jiangxi University of Science and Technology, Ganzhou 341000, China）
Abstract:The electrochemical reduction mechanism of Mg2+ on the tungsten electrode at 1173 K was studied through the methods of cyclic voltammetry, chronopotentiometry and chronoamperometry using MgO and LiF-MgF2-BaF2-KCl as raw material and molten salt. The results show that the electrochemical reduction of Mg2+on the tungsten electrode is a two-electron transition process by one step. The electrode reaction is Mg2++2e→Mg. During depositing process, the nuclear polarization phenomenon is observed. The depositing process of Mg is an irreversible reaction controlled by diffusion, and the diffusion coefficient of Mg2+ in the molten salt is 1.28×10-5 cm2/s at 1173 K.
Key words: magnesium oxide; molten salt; electrochemical reduction; diffusion control
