熔盐电化学分离核能系统中镧系金属离子的研究

项目名称： 熔盐电化学分离核能系统中镧系金属离子的研究

项目编号： No.51274102

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 矿业工程

项目作者： 李冰

作者单位： 华东理工大学

项目金额： 80万元

中文摘要： 课题以钍基熔盐堆系统为背景，拟采用电化学方法全面系统解决熔盐反应堆后处理过程中镧系金属离子与锕系金属离子以及熔盐电解质分离的科学问题，为反应堆后处理工艺的设计提供重要的理论依据。课题拟通过电化学方法，包括循环伏安、方波伏安以及计时电流和计时电位，结合化学分析手段，表征镧系金属离子在不同熔盐体系中的氧化/还原电位、电化学还原机理和控制步骤、存在的价态，以及不同价态之间的平衡常数，获得镧系元素价态稳定性与熔盐支持电解质阴离子的关系。通过高温拉曼光谱表征镧系元素的离子结构与支持电解质阴离子的关系，以及与还原电位之间的内在联系。从而分别获得三价镧系元素最稳定、二价最不稳定的氟化物、氯化物以及氟-氯化物电解质体系。采用恒电位/恒电流电解方式分离镧系金属离子，采用搅拌的方式提高反应动力学，在氟化物电解质体系中添加氮离子，考察电位，电流密度、低价离子、温度、电解质体系对镧系元素分离效率和分离速度的影响。

中文关键词： 稀土金属离子；电化学；阴极过程；分离提取；阳极过程

英文摘要： Based on the TMSR(Th-molten salts reactor )system, electrochemcial method is applied to deal with the overall scientific issues concerning the separation of the lanthanides from the molten salts and actinides in the reprocessing of the molten salts reactors. The results will provide a significant important theoretical support for the technical design of the reprecessing for TMSR system. By electrochemcial methods including cyclic volatmmograms, square-wave voltammograms,and chronoamperograms and chronopotentiograms, combined with chemical analysis method，the redox potential，electrochemical reduction mechanism and controlled steps and valences of lanthanides in the molten salts are characterized. And the equilibrium constant between two oxidation states also will be obtained.The correlation between the stability of divalence and trivalence for the lanthanides ions with the anion ions of the supporting electrolyte will be studied.The lanthanides ions structure will be measured by high-temperature Raman spectroscopy,and the correlation between ions structure and anion ions of supporting electrolyte, as well as the inherent relationship between ions structure and the reduction potentials of lanthanides also will be discussed.Therefore,flourides, chlorides and mixture of floruide-chloride with the most stable trivale

英文关键词： rare-earth metal ions；electrochemical；cathode process；separation and extraction；anode process