三正辛胺萃取色层法分离铀、钍和放射性核素
SEPARATION OF U, Th AND RADIONUCLIDES BY TNOA EXTRACTION COLUMN CHROMATOGRAPHY
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摘要: 本文测定了三正辛胺(TNOA)-聚氯乙烯色层粉在盐酸体系中对铀的吸附分配,观察到固定相中萃取剂浓度以及水相中盐酸和盐析剂(LiCl)浓度对吸附分配的影响,都与TNOA-HCl体系液液萃取机理相符合。色层粉对铀的吸附量随水相铀浓度的增加而增大,能满意地符合弗赖德利胥(Freundlish)吸附公式。 此外,应用三正辛胺萃取色层法,以7.5M盐酸溶液为流动相,成功地从常量钍中分离了微量铀。方法简单,回收率高。该法还用于铀、钍和长寿命裂变产物的分离,以及一些放射性核素相互之间的分离,都获得了比较满意的结果。Abstract: The adsorption coefficients of uranyl ions between TNOA-treated polyvinyl chloride (PVC) powder and hydrochloric acid have been measured in batch experiments. It has been found that the effect of the concentration of TNOA in the stationary phase and the concentrations of HC1 and LiCl on the adsorption coefficient of uranyl ions were similar to the liquid-liquid extraction in the TNOA-HC1 system. The adsorption capacity of TNOA treated PVC powder increased on increasing the concentration of uranyl ions in aqueous solution and followed the Freundlish adsorption equation. The effect of y-radiation on the adsorption capacity of TNOA-treated PVC powder has also been described.The separation of U, Th and radionuclides by TNOA column extraction chromatography has been studied. Microgram uranium can be completely separated from a bulk amount of thorium by TNOA-PVC column with 7.5M HC1 as the eluent. Such a column was also applied to the separation of U, Th and other long-life fission products.