基于低温制备色层法的溶解尾气中氪-85纯化装置与方法

Research on Purification Device and Method of Krypton-85 in Dissolved Tail Gas Based on Low Temperature Preparation Chromatography

^(85)Kr是一种非常有价值的放射性气态核素。目前,我国^(85)Kr气体基本依赖进口满足市场需求。纯化作为^(85)Kr产业提取-纯化一体化生产系统的重要技术,是获得高纯度^(85)Kr的重要手段,因此在进行纯化热实验以及正式的工业生产前需要进行冷实验确定纯化过程的重要参数。搭建了基于低温制备色层法的纯化冷实验台架,研究了色层柱填料和温度对氪气纯化效果的影响,结果表明:椰壳活性炭具有比5A分子筛更好的纯化效果;采用椰壳活性炭填充色层柱,色层柱温度降低至-40℃时,氪气可以和氮气、氧气等杂质完全分离,氪气的纯化效果较好,产品气中氪-84的峰显著高于氮气和氧气,氪气的纯度大幅提高。

^(85)Kr is a highly valuable radioactive gaseous nuclide.At present,China's ^(85)Kr gas basically relies on imports to meet its usage demand.As an important technology of ^(85)Kr industrial extraction and purification integrated production system,purification is an important means to obtain high-purity ^(85)Kr.Therefore,it is necessary to carry out non-radioactive test to determine the important parameters of the purification process before the purification radioactive test and formal industrial production.In this study,a non-radioactive test bench based on low temperature preparation chromatographic method was set up to study the influence of chromatographic column packing material and temperature on the purification effect of krypton gas.The results showed that the coconut shell activated carbon had better purification effect than 5A molecular sieve;when the temperature of the chromatography column filled with coconut shell activated carbon decreased to-40℃,Kr could be completely separated from impurities such as nitrogen and oxygen,the purification effect of krypton gas was better,and the peaks of Kr-84 in the product gas were significantly higher than those of N2 and O2,and the purity of krypton gas was greatly improved.