铀化合物与不同氟化剂反应的高温热力学  

High-temperature thermodynamics for fluorinating uranium compounds

作　　者：戴建兴[1] 张焕琦[1] 李晴暖[1] 吴国忠[1] 

机构地区：[1]中国科学院上海应用物理研究所,上海201800

出　　处：《核技术》2012年第9期704-708,共5页Nuclear Techniques

基　　金：中国科学院战略性先导科技专项(XDA01020304)资助

摘　　要：高温氟化物挥发法是一种用于分离和获取高纯度铀的核燃料干法分离工艺。该工艺技术成熟,分离得到的铀品质好,但因高温氟化的反应条件对设备材质要求苛刻,该方法在乏燃料后处理领域未能得到很好的发展。本文通过比较不同氟化剂与铀化合物发生氟化反应时的反应热及反应平衡常数,着重探讨了采用对设备材料腐蚀相对较弱的NF3替代F2的理论可行性。结果表明,NF3替代F2作为氟化剂在反应热力学上是可行的;氟化反应时放出的反应热也不会对熔融盐反应体系的温度带来剧烈影响。High temperature fluoride volatility method （FVM） is a pyroprocessing technique for separation and recovery of high-purity uranium. However, it is not well developed in the field of spent fuel reprocessing due to tough requirements on equipment and materials for high temperature fluorination. In this paper, the feasibility of replacing F2 by NF3, which is less corrosive, is investigated emphatically by comparing the reaction enthalpy and the equilibrium constant for different fluorinating agents with U compounds. The results show that the NF3 as an alternative agent is feasible in thermodynamics; and the exothermic enthalpy of reaction does not bring drastic changes in temperature.

关 键 词：铀 高温化学 氟化反应 热力学 三氟化氮 

分 类 号：TL244[核科学技术—核燃料循环与材料]