Liu Zhongyun, Cao Yuhe, Koros William J
School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, 311 Ferst Drive, 30332, Atlanta, GA, USA.
Angew Chem Int Ed Engl. 2025 Jan 10;64(2):e202414683. doi: 10.1002/anie.202414683. Epub 2024 Nov 2.
Asymmetric carbon molecular sieve (CMS) hollow fiber membranes with tunable micro- and macro-structural morphologies for energy efficient propylene-propane separation are reported here. A sub-glass transition temperature (sub-Tg) thermal oxidative crosslinking strategy enables simultaneous optimization of the intrinsic molecular sieving properties while also reducing the thickness of the CMS "skin" derived from the 6FDA : BPDA/DAM polyimide precursors. Such synergistic tuning of CMS microstructure and macroscopic morphology of CMS hollow fibers enables significantly increased propylene permeance (reaching 186.5 GPU) while maintaining an appealing propylene/propane selectivity of 13.3 for 50/50 propylene/propane mixed gas feeds. Our findings reveal a more refined and versatile tool than available with previous O-doping pretreatments. The advanced approach here should be broadly useful to other polyimide precursors and diverse gas pairs.
本文报道了具有可调微观和宏观结构形态的不对称碳分子筛（CMS）中空纤维膜，用于高效的丙烯-丙烷分离。亚玻璃化转变温度（sub-Tg）热氧化交联策略能够在优化固有分子筛分性能的同时，降低由6FDA : BPDA/DAM聚酰亚胺前驱体制备的CMS“皮层”的厚度。CMS中空纤维微观结构和宏观形态的这种协同调节，使得丙烯渗透率显著提高（达到186.5 GPU），同时对于50/50丙烯/丙烷混合气体进料，保持了13.3的可观丙烯/丙烷选择性。我们的研究结果揭示了一种比以往O掺杂预处理更精细、更通用的工具。这里提出的先进方法应该对其他聚酰亚胺前驱体和各种气体对具有广泛的适用性。
