国外核燃料后处理化学分离技术的研究进展及考察_韦悦周

第23卷第7期2011年7月

化学进展

PROGRESS IN CHEMISTRY

Vol．23No．7Jul．2011

收稿：2011年1月，收修改稿：2011年3月*Corresponding author

e-mail ：yzwei@sjtu．edu．cn

国外核燃料后处理化学分离技术的研究进展及考察

韦悦周

*

（上海交通大学核科学与工程学院

上海200240）

摘

要

后处理技术可分为使用水溶液的湿法和不使用水溶液的干法。湿法主要有溶剂萃取法（液液

萃取法）、

离子交换法和沉淀法等。以TBP （磷酸三丁酯）为萃取剂的PUREX 法是当今后处理的主流技术。通过PUREX 流程，可回收乏燃料中约99.5%的铀和钚，但由于长寿命次锕系元素（MA ：Np 、Am 、Cm ）以及Tc 等得不到有效的分离回收，放射性废物的放射毒性仅降低一个量级。并且该技术本身存在萃取工艺流程复杂，设备规模大，产生大量的难处理有机废液等问题。多年来世界核能主要国家都在致力于改良PUREX 流程的同时，开展更先进的湿法后处理技术研发。干法后处理采用熔盐或液态金属作为介质，主要有电解精炼法、

金属还原萃取法、沉淀分离法和氟化物挥发法等。具有装置规模较小，耐辐照性强，临界安全性高等优点。但分离性能较低，且由于操作温度高（数百摄氏度），材料耐用性以及操作可靠性尚待解决。近年来干法作为金属燃料后处理以及超铀元素嬗变燃料处理的分离技术，重新受到重视。本文概括介绍了国外先进湿法和干法后处理技术的研究动向，

并对分离技术中的主要化学问题进行了分析和考察。关键词

乏燃料

化学分离

湿法后处理

干法后处理

中图分类号：TL941；O652.6

文献标识码：A

文章编号：1005-281X （2011）07-1272-17Progress and Discussion on Chemical Separation Technologies

for Nuclear Fuel Reprocessing Developed Abroad

Wei Yuezhou *

（School of Nuclear Science and Engineering ，Shanghai Jiao Tong University ，Shanghai 200240，China ）Abstract

Reprocessing technologies can be divided into wet process using aqueous solution and dry process．

The wet process includes solvent extraction （liquid-liquid extraction ），ion exchange ，precipitation ，etc．The PUREX process which uses TBP as extractant and can recover about 99.5%of the U and Pu from spent fuel is the only successfully commercialized reprocessing technology nowadays．However ，the PUREX process still has some significant drawbacks such as complicated extraction procedures ，generation of a great amount of waste and utilization of large scale equipment．In addition ，it can not effectively recover the long-lived nuclides such as minor actinides （Np ，Am ，Cm ）and Tc ，which will result in a long term radiological effect on the environment．In recent years ，many efforts have been devoted to the improvement of the PUREX process and the study of advanced wet reprocessing technologies．Dry process utilizing electro-refining in molten salt ，reductive extraction in liquid metal or volatilization of fluorides is attracting wide attention ，because it has the advantages of compact equipment ，high radiation resistance and critical safety．But relatively low separation factor and corrosion of materials at high temperature are the main problems of the dry process．This article reviews the progress in the chemical separation technologies for nuclear fuel reprocessing abroad．Furthermore ，some chemical problems in separation processes are analyzed and discussed．

Key words

spent nuclear fuel ；chemical separation ；wet reprocessing ；dry reprocessing