带羟基的磷酸酯对PUREX流程中第三相的形成影响初步研究  

Behavior of Third Phase of Mixed Solution Containing Hydroxyphosphate in PUREX Process

作　　者：罗英杰 吴瑞才 陈港 唐双凌[1] LUO Ying-jie;WU Rui-cai;CHEN Gang;TANG Shuang-ing(School of Environmental and Biological Engineering,Nanjing University of Science and Technology,Nanjing 210000,China)

机构地区：[1]南京理工大学环境与生物工程学院,江苏南京210000

出　　处：《核化学与放射化学》2025年第2期126-132,I0001,共8页Journal of Nuclear and Radiochemistry

基　　金：乏燃料后处理科研专项(1161020387)。

摘　　要：在乏燃料后处理PUREX流程中,磷酸三丁酯(TBP)在辐射和高温条件下可能会形成磷酸二丁酯(HD-BP)和带羟基的磷酸酯,其与30%(体积分数,下同)TBP-煤油、HNO_(3)和锆(Zr^(4+))混合接触时,易在水相和油相之间形成第三相。第三相的形成会对后处理过程造成严重影响。通过合成带羟基的磷酸酯,并对Zr/HDBP-30%TBP-煤油/HNO_(3)/带羟基的磷酸酯混合溶液第三相的生成情况进行研究,探讨Zr^(4+)浓度、HDBP浓度以及带羟基的磷酸酯质量浓度对第三相的影响。结果表明,Zr^(4+)浓度为0~3×10^(-2) mol/L时,第三相的生成量与Zr^(4+)浓度呈正相关性;HDBP质量浓度为0~25 g/L时,第三相的生成量先升高后降低;带羟基的磷酸酯会极大影响第三相生成量,当其质量浓度为0~60 g/L时,第三相的生成量先逐渐升高后基本保持不变。利用X射线衍射仪和红外光谱,分析第三相的基本结构,结果表明第三相为无定型状态的非晶体,结构主要为Zr-DBP型。During spent fuel reprocessing,TBP may form hydroxyl-containing phosphate ester under radiation and high temperature conditions.The phosphate ester with hydroxyl group is a substance with hydrophilic and lipophilic groups,which is prone to form a third phase between the aqueous phase and the oil phase when mixed and contacted with 30%TBP-kerosene,HNO_(3),HDBP and zirconium(Zr^(4+)).Moreover,part of the oil and water phases will also be encapsulated in the third phase,so that the generation of the third phase is greatly increased.The generation of the third phase will cause density effect and volume effect,reduce the decontamination efficiency of the extractant,and even cause liquid flooding,inverted phase and other abnormalities during the operation of the equipment,thus affecting the normal operation of the process.In this paper,the hydroxyl-containing phosphate ester was synthesized and the generation of the third phase in the mixed solution of Zr/HDBP-30%TBP-kerosene/HNO_(3)/hydroxyl-containing phosphate ester was studied,to investigate the effects of zirconium concentration,HDBP concentration and mass concentration of hydroxyl-containing phosphate ester on the third phase.The results show that the generation of the third phase is positively correlated with the zirconium concentration in the range of 0-3×10^(-2) mol/L,the generation of the third phase is firstly increased and then decreased in the range of 0-25 g/L for HDBP,and the generation of the third phase is firstly increased rapidly and then basically remained unchanged in the range of 0-60 g/L for the mass concentration of hydroxyl-containing phosphate ester.The basic structure of the third phase is analyzed by using X-ray diffractometer and infrared spectroscopy,and the results show that the third phase is an amorphous state amorphous body,and the structure is mainly of Zr-DBP type.

关 键 词：乏燃料后处理 第三相 磷酸二丁酯 Zr^(4+) 带羟基的磷酸酯 

分 类 号：TL283[核科学技术—核燃料循环与材料]