Zr(IV)在NaCl-KCl-K2ZrF6熔盐体系中的电结晶机理

熔盐电解精炼法是乏燃料后处理的一种重要方法,电沉积和结晶机理研究对U、Zr等金属分别回收具有重要意义。在高温熔盐三电极体系下，以铂丝作为研究电极、热解石墨坩埚作辅助电极、Ag/AgCl作为参比电极，采用循环伏安法和计时电流法开展研究。研究了温度为1023 K时Zr(IV)在NaCl-KCl-K2ZrF6熔盐体系中的电结晶成核机理，通过电化学理论分析和恒电位电解产物微观形貌分析得到锆晶核在铂电极上的成核机理为连续成核，成核长大机理为扩散控制的三维半球形螺旋生长机理。为电解精炼提纯金属锆以及乏燃料后处理的研究提供一定的参考。

Study on the electrocrystallisation of Zr(IV) in NaCl-KCl- K2ZrF6molten salt

Molten salt electrorefining is an important method for spent fuel reprocessing. The study of electrodeposition and crystallization mechanism is of great significance for recovering U, Zr metals respectively. In three-electrode system, platinum wire was used as research electrode, pyrolytic graphite crucible as auxiliary electrode, Ag/AgCl as reference electrode, and cyclic voltammetry and chronoamperometry were used to study the process. The electrochemical nucleation of zirconium in NaCl-KCl-K2ZrF6 molten salt at 1023 K was investigated by chronoamperometry. Electrochemical theory analysis and the micro-morphology analysis of the potentiostatic electrolysis product of zirconium nuclei in the process of growing up showed that the growth mode of zirconium nuclei was three-dimensional hemispherical spiral growth limited by the diffusion of the zirconium complex ions.