离子液体体系的萃取行为及其在乏燃料后处理中的应用前景  

Extraction Behaviors of Ionic Liquid Systems and Application Perspectives in Reprocessing of Spent Nuclear Fuel

作　　者：刘海望[1] 杨涛[1] 陈庆德[1] 沈兴海[1] 

机构地区：[1]北京大学化学与分子工程学院放射化学与辐射化学重点学科实验室北京分子科学国家实验室,北京100871

出　　处：《核化学与放射化学》2015年第5期286-309,共24页Journal of Nuclear and Radiochemistry

基　　金：国家自然科学基金资助项目(91226112;20871009)

摘　　要：离子液体由于其特有的性质,在乏燃料后处理中的应用已受到广泛关注。本文综述了不同种类离子液体中多种萃取剂对乏燃料所含若干锕系元素及放射性裂片元素的萃取,重点分析了不同萃取体系的萃取效率、萃取选择性、萃取机理和反萃等关键问题。综合目前的研究成果,可发现:离子液体-萃取剂体系由于其独特的萃取机理,通常比传统萃取体系具有更高的萃取效率;一些萃取体系具有高选择性使其在乏燃料后处理中有很好的应用前景。在简要介绍阳离子交换机理、阴离子交换机理和中性复合物机理三种离子液体体系萃取机理的同时,重点总结了萃取中三相问题和协同萃取效应。本文还总结了液-液反萃、超临界CO2反萃和电化学反萃三种常见的反萃方法,讨论了各自的优缺点。本文最后对离子液体在乏燃料中的应用进行了总结与前景展望。The application of ionic liquids(IL)in the reprocessing of spent nuclear fuel has attracted much attention for their characteristic properties.In this article,the recent progress about extraction behaviors of some actinides and fission products in spent nuclear fuel by various extractants in different ionic liquids was reviewed.Especially,the key issues concerning the efficiency,selectivity and mechanism of extraction as well as stripping in different ionic liquid-based extraction systems were discussed.By summarizing the present research,we could find that the extraction efficiency in IL extraction systems was often higher than that in traditional extraction systems because of its extraction mechanism and theextraction selectivity of some ionic liquid-based extraction systems was good,indicating their application prospect in extraction.After the introduction of three mechanisms in IL-based extraction(i.e.,cation-exchange mechanism,anion-exchange mechanism and solvation mechanism),the third phase problem and synergistic extraction were summarized.Three common methods of stripping(i.e.,liquid-liquid stripping,supercritical CO2 stripping and electrochemical stripping)were also discussed from their advantages and disadvantages.Finally,the research results were concluded and the application foreground of ionic liquidbased extraction systems was presented.

关 键 词：离子液体 萃取 反萃 乏燃料后处理 

分 类 号：TL24[核科学技术—核燃料循环与材料]