【摘要】 本文综述了稀土熔盐电解的工艺技术现状和问题,分析了造成RECl₃-KCl体系电解稀土金属时电流效率低的原因,其中包括电解工艺条件、原料中的杂质、变价稀土元素和稀土金属溶解等,并对提高稀土熔盐电解制取稀土金属电流效率的途径进行了讨论。更多还原

【Abstract】 This paper begins with a comprehensive description of the present status and problems in the electrolytic process of molten rare earth metal salts. Then it analyses the cause of low current efficiency in the electrolysis of RECl₃-KCl system. Although the optimum conditions, including temperature, molten salt composition and current density have been studied in detail and adopted in industrial production, the current efficiency is still lower than 40%. The influence of trace content of impurities, such as H₂O, SO_4^2-, PO_4^3-, Ca, Mn, Mg, Al, Pb, Fe and Si, upon current efficiency has been noted, while the valencc variation and solubility of some rare earth metals in molten salt are still not neglected. For instance, Sm³⁺ and Eu³⁺ are only reduced to Sm^z+ and Eu²⁺ on cathode and oxidized again in anode and Nd metal can be dissoluble in molten salt so as to decrease the current efficiency. Furthermore, this paper suggests the necessity of purifying the raw materials before electrolysis and employing the （La-Ce）Cl₃ group in order to improve the current efficiency.更多还原