大粒径二氧化硅基树脂材料的合成及其对锝-99的分离研究

开展放射性废液中99Tc的分离研究对于推进我国先进乏燃料后处理以及放射性废物处置技术的发展具有重要的科学意义。本项目拟通过对二氧化硅微球载体的可控合成和99Tc选择性分离官能团的研究，开发一种可用于高酸度、高盐度放射性废液中99Tc高效分离的树脂材料。在课题组前期工作的基础上，研究大粒径、大孔径和高稳定性二氧化硅微球合成方法，研发惰性SiO2-P载体的原位聚合技术，利用化学法和物理法研究特异官能团化合物（季铵盐和吡啶类）与惰性载体的牢固接枝技术，以期合成一种对99Tc高效的分离树脂材料。通过表征技术对基体材料和树脂材料的结构性质进行分析，采用批式法和柱实验系统研究树脂材料对不同介质中99Tc的分离性能，建立放射性废液中99Tc的色谱分离方法，为乏燃料后处理过程中长寿命裂片核素的分离提供新思路和新途径。

Separation of 99Tc from radioactive liquid waste is of great scientific significance for the development of advanced spent fuel reprocessing technology and radioactive waste disposal. This project aims to develop a highly efficient resin material for the effective separation of 99Tc from highly-acidic and highly-saline radioactive liquid waste in reprocessing plant through the controlled synthesis of silica microsphere carrier and selective separation functional group of 99Tc. Based on our previous work, a method will be developed for synthesis of large size silica microspheres with large aperture and high stability, in-situ polymerization of inert SiO2-P carriers, and firmly grafting of specific functions (quaternary ammonium salt and pyridine class) on inert carrier (SiO2-P) by using chemical method and physical method. The structural properties of matrix material and functional resins were analyzed by characterization technology. The resin will be investigated for separation of 99Tc from different solution using batch and column experiment, and a chromatographic method for separation of 99Tc from radioactive liquid waste will be developed and demonstrated. This will provide new approach and idea for the separation of long-life fission products in the reprocessing process of spent fuel for their transmutation and safe repository.