碳酸钠焙烧对铀锆混合氧化物中铀溶解率的影响  

Effect of Roasting With Sodium Carbonate on Dissolution of Uranium-zirconium Mixed Oxide

作　　者：袁波 尹荣才[1] 卢长先[1] 龙弟均 曾诚 范经伦 YUAN Bo;YIN Rongcai;LU Changxian;LONG Dijun;ZENG Cheng;FAN Jinglun(National Key Laboratory for Nuclear Fuel and Materials,Nuclear Power Institute of China, Chengdu 610041,China)

机构地区：[1]中国核动力研究设计院反应堆燃料及材料重点实验室

出　　处：《湿法冶金》2019年第3期187-190,共4页Hydrometallurgy of China

摘　　要：研究了碳酸钠焙烧对铀锆混合氧化物中铀溶解率的影响。结果表明:铀锆混合氧化物中的难溶铀主要以固溶体UxZryO2形式存在,碳酸钠焙烧可破坏固溶体结构,提高铀溶解率;焙烧过程中,ZrO2由四方相转为单斜相,U3O8转为易溶解的铀酸盐;在900℃下加碳酸钠焙烧,碳酸钠添加量为铀锆氧化物质量的0.25倍时,焙烧产物铀溶解率达99%,溶解渣中铀质量分数低至1%以下。The influence of roasting with sodium carbonate on dissolution of uranium-zirconium mixed oxide was investigated.The experimental results indicate that insoluble uranium mainly exists in the form of U x Zr y O 2 solid solution in the oxide.Roasting with sodium carbonate can destroy the solid solution structure and improve effectively the dissolution of uranium.Zirconium dioxide is converted from tetragonal to monoclinic phase and uranium octaoxide is converted to the more soluble salts during calcination.The dissolution of uranium is over 99% and the residual uranium is less than 1% under the conditions of roasting temperature of 900 ℃,mass ratio of sodium carbonate-to-mixed oxide of 0.25.

关 键 词：铀锆混合氧化物 碳酸钠 焙烧 铀 溶解 

分 类 号：TL211[核科学技术—核燃料循环与材料]