氯化锂熔盐中八氧化三铀电解还原基础研究

将氧化物乏燃料直接电解还原为粗金属的过程是目前以电解还原-电解精炼为特征的主流干法后处理流程的重要步骤。二氧化铀（UO₂）是乏燃料的最主要成分，将致密的UO₂芯块转化为八氧化三铀（U₃O₈）粉末后，再进行电化学还原能有效提高还原速率。因此，以U₃O₈为研究对象，开展其在氯化锂（LiCl）熔盐中的电解还原机理研究，对后处理干法流程的开发具有重要的现实意义。本文在650 ℃的LiCl熔盐中，采用循环伏安法和恒电位电解法，研究U₃O₈的电解还原行为；对电解后的样品，运用XRD、SEM等手段分析其组成和形貌，并推测相应的还原机理。

Electroreduction Fundamental Study of Solid U3O8 in Molten LiCl

Direct reduction of spent oxide fuel to mix-metal is the key step of an important dry reprocessing process, which is feature with electroreduction-electrorefinning. UO₂ is the main component in spent fuel. The transform of compact UO₂ pellet to U₃O₈ powder could effectively improve the electroreduction rate. Therefore, taking U₃O₈ as research object, studying its electrochemical behaviors during the electroreduction process has certain practical significance for the development of this process. In this paper, the electroreduction behaviors of U₃O₈ in molten LiCl (650 ℃) were studied using cyclic voltammetry and constant potential electrolysis technology. The after electrolysis products were analyzed by XRD and SEM. Finally, a reduction mechanism was also proposed.