Liu Yi, Li Mingrun, Chen Zhigang, Cui Yi, Lu Jinming, Liu Yi
State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Linggong Road NO. 2, Ganjingzi District, Dalian, 116024, China.
State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Zhongshan Road NO. 457, Shahekou District, Dalian, 116023, China.
Angew Chem Int Ed Engl. 2021 Mar 29;60(14):7659-7663. doi: 10.1002/anie.202017087. Epub 2021 Mar 1.
Microstructural optimization (such as thickness and preferred orientation) is a major concern for performance enhancement of zeolite membranes. In this study, we demonstrated that the introduction of hierarchy easily enabled concurrent thickness reduction and orientation control of zeolite membranes. Specifically, hierarchical MFI zeolite membranes comprising higher degree of (h0h) preferentially oriented ultrathin (ca. 390 nm) selective top layers and porous intermediate layers on porous α-Al O substrates were fabricated. The use of hollow-structured MFI nanoseeds and the employment of single-mode microwave heating during membrane processing were found indispensable for the preparation of MFI zeolite membranes with superior butane isomer separation performance, thereby surpassing the current n-/i-butane selectivity versus n-butane permeance trade-off limits of MFI zeolite membranes prepared via solution-based synthetic protocols.
微观结构优化（如厚度和择优取向）是提高沸石膜性能的主要关注点。在本研究中，我们证明引入层级结构能够轻松实现沸石膜的厚度降低和取向控制。具体而言，制备了具有高度（h0h）择优取向超薄（约390 nm）选择性顶层以及多孔α-Al₂O₃基底上多孔中间层的层级MFI沸石膜。发现使用中空结构的MFI纳米晶种以及在膜制备过程中采用单模微波加热对于制备具有优异丁烷异构体分离性能的MFI沸石膜必不可少，从而突破了通过基于溶液的合成方法制备的MFI沸石膜目前的正丁烷/异丁烷选择性与正丁烷渗透率的权衡限制。
