氙气(Xe)是一种优良的麻醉剂，在欧洲已实现商业应用；Xe产能不足是制约其全球推广的关键性瓶颈。膜法在线脱除人体麻醉过程中呼出的CO2能够实现Xe高效循环套用，为Xe供应开辟新途径。如何消除分子间竞争吸附和上坡扩散，提升膜通量，是膜分离技术能否推向实际应用的关键。本项目提出构筑双级孔全硅STT分子筛膜用于CO2/Xe分离，通过膜孔道和表面性质调控，提升膜选择性和通量。项目提出原位相转化法在中空纤维载体上制备膜分离层；然后通过高温固相反应在分子筛膜表面引入骨架杂原子以构筑弱氙气吸附表面，研究表面性质与分离性能之间的匹配关系；采用先骨架原子杂化后阳离子交换的方法调控传质孔道荷电性，提高CO2/Xe吸附选择性；开展气体膜分离过程研究，建立二元竞争吸附气体分子在分子筛膜中传质数学模型，揭示气体分子尺寸和竞争吸附与分子筛膜传质过程的相互作用规律。

Membrane separation could efficiently separate CO2, generated by human tissue in the closed-circuit anesthesia system, from xenon (Xe). This technique exhibits great potential to break the “supply ceiling” of xenon from the cryogenic distillation of air. It has proven that the competitive adsorption between Xe and CO2 plays a key role in the permeation flux and selectivity of the zeolite membrane. Herein, an all-silica STT zeolite membrane supported on ceramic hollow fibers is proposed for CO2/Xe separation. STT zeolite is featured with a 2D channel in xz planes: the first pathway (PW1) lies along the [001] direction and has an aperture size of 0.37×0.53 nm; the second pathway (PW2), with an aperture size of 0.24×0.35 nm, is interconnected with the first pathway. It is proposed to improve the membrane selectivity and permeation flux by tuning the aperture size and surface property. The all-silica STT zeolite membrane would be prepared by a phase transition from an amorphous silica layer to a crystalline structure. The incorporation of other atoms, involving Al, Ge, or B, would be achieved by solid reaction at high temperature, targeting a weak interaction with Xe. The electrical density would be tuned by ions exchange for an enhanced CO2/Xe adsorption selectivity. Based on the gas permeation, a mechanism would be proposed to explain the effects of competitive adsorption on separation performance of STT zeolite membranes for CO2/Xe separation. Finally, the CO2 and Xe transfer property would be described by the Maxwell-Stafen equation. All of these efforts would be beneficial to the membrane material design and real application of Xe purification.