二环己基18-冠醚-6对放射性废液中^(90)Sr的萃取性能研究

Study on the extraction performance of ^(90)Sr from radioactive waste liquid by dicyclohexyl-18-crown-6

^(90)Sr(T_(1/2)=28.9 a)是一种高毒类长寿命β放射性核素,是高放废物处理中主要热源之一。高放废物在进行处置之前必须准确测量放射性废物中^(90)Sr的含量,而将^(90)Sr从放射性废物中分离出来是其准确测量的关键。本文采用溶剂萃取法,以二环己基18-冠醚-6(DCH18C6)为萃取剂,分别研究了水相酸度、萃取剂浓度、杂质离子浓度等对锶萃取性能影响,确定了放射性废液中^(90)Sr的选择性分离的最佳萃取条件。根据实验获取的最佳萃取条件,开展了DCH18C6萃取体系对放射性废液中^(85)Sr、^(89)Sr的萃取性能验证实验,最后采用DCH18C6萃取体系成功分离放射性蒸残液中^(90)Sr,建立了一种有效的快速分离放射性废液中^(90)Sr的方法。

^(90)Sr(T_(1/2)=28.9a)is a long-lived beta radionuclide with high toxicity,which is one of the main heat sources in high discharge waste treatment.High discharge waste must accurately measure the radioactive waste content of ^(90)Sr before disposal,and separating ^(90)Sr from radioactive waste is critical.In this paper,solvent extraction method was used.Dicyclohexyl^(-1)8-crown-6 was used as the extractant,the influence of aqueous acidity,extractant concentration,impurity ion concentration on strontium extraction performance,were studied respectively.The optimal extraction conditions for the selective separation of ^(90)Sr in radioactive waste liquid was determined.Based on the experimental results,the isotope ^(85)Sr and ^(89)Sr of extraction performance verification experiments were carried out.Finally,^(90)Sr of radioactive waste sample was separated by the selected crown ether extraction system and an effective method of quickly separating ^(90)Sr in the radioactive waste liquid was obtained.