阴离子-极性配体双功能化超微孔材料的设计合成与氙/氪分离性能

氙气和氪气的分离是高纯氙气制备和核裂变尾气回收利用中的关键环节，目前主要通过高能耗、高成本的低温精馏过程实现分离。吸附分离是清洁、低耗的气体分离方法，但常规吸附材料普遍存在氙/氪选择性低、选择性与吸附容量难以兼顾的不足。本申请拟设计合成强极性功能位点密度高、孔径与氙/氪气体动力学直径相匹配且精细可调的阴离子-极性配体双功能化超微孔材料，从位点协同和尺寸效应两方面同时强化氙/氪分离性能，获得高氙/氪选择性与高吸附容量。为此，拟研究阴离子-极性配体双功能化超微孔材料的结构性质调控规律及其与氙气/氪气的相互作用规律，评价阴离子-极性配体双功能化超微孔材料对氙/氪混合气体的分离性能，并研究氙气/氪气在该类材料中的扩散和传递特性。项目组在超微孔材料设计合成和结构相似物高效分离方向已有多年的研究工作积累。预期研究成果将对绿色、高效氙/氪分离新方法的建立作出贡献。

The separation of xenon (Xe) from krypton (Kr) is crucial for the production of high-purity xenon and the utilization of nuclear reprocessing off-gas. Currently the main separation method is cryogenic distillation which suffers from high energy consumption and high production cost. Adsorption is regarded as clean and low-cost method for gas separation, but the Xe/Kr selectivity of traditional adsorbents is usually low, and a trade-off between Xe/Kr selectivity and adsorption capacity exists. This project will design and synthesize anion-polar ligand bi-functionalized ultra-microporous materials which possess high density of strongly polar active sites and tunable pore size that matches the dynamic diameter of Xe/Kr. These materials can improve the Xe/Kr separation efficiency from both the site-synergistic effect and the size effect, bringing about both high Xe/Kr selectivity and high adsorption capacity. Thus, this project will study the structure and property of anion-polar ligand bi-functionalized ultra-microporous materials and explore their interaction with Xe/Kr, and will examine the separation performance of Xe/Kr gas mixture by those materials as well as the Xe/Kr diffusion and transfer characteristics. The research group has good experience in the design of ultra-microporous materials and the separation of structurally related compounds. The expected research results will contribute to the development of green and highly efficient new method of Xe/Kr separation.