离子液体-萃取树脂的制备及其对Pb-210中Po-210的分离研究

Po-210是天然铀衰变系中的放射性核素，由于其毒性强而受到广泛关注，是生态环境放射性安全方面重点监测的核素。由于Po-210的半衰期短（138.4天），用于保障测量结果准确可靠的Po-210标准物质需要定期更新，因此，需要研究一种能够快速分离Po-210的方法。离子液体-冠醚树脂在分离锶、钇方面比辛醇-锶树脂有明显提高，结合离子液体的优点，本项目拟筛选1种对Po-210有较好萃取效果的萃取剂，并选择一种离子液体作为稀释剂，制备成离子液体-萃取树脂，测定树脂柱的固定相体积、流动相体积，研究该离子液体-萃取树脂在盐酸、硝酸介质中对Po-210的分离行为，探索可能的分离机理。设计从Pb-210、Bi-210、Po-210平衡体系中分离Po-210的放射化学流程，运用液体闪烁计数法分析用该流程得到的Po-210产品中Pb-210、Bi-210的杂质含量。

Po-210 is one of products of natural uranium decay series. It is a significant monitoring radionuclide in the radioactive safety of ecological environment, due to its strong radioactive toxicity. Po-210 reference source used for ensuring accuracy and reliability of measurement results needs to be updated regularly, as the short half-life (138.4 days) of Po-210. Therefore, it is necessary to investigate a method that can rapidly separate Po-210. The separation of strontium and yttrium by crown ether – ionic liquid resin is significantly higher than that by crown ether – octanol resin. In this project, one extractant that is suitable for extracting Po-210 and one ionic liquid will be chosen to prepare extraction resin as a consideration of the advantages of ionic liquid. The volume of stationary phase and volume of mobile phase will be measured. The separation behavior of Po-210 in hydrochloric acid and nitric acid medium by ionic liquid based extraction chromatographic resin will be investigated. And the possible mechanism will be discussed. A radiochemical process of separating Po-210 from Pb-210, Bi-210 and Po-210 equilibrium systems will be designed. And the radioactive impurity of Pb-210 and Bi-210 in Po-210 solution obtained by this process will be analyzed by liquid scintillation counting.