Borne Isaiah, He Donglin, DeWitt Stephen J A, Liu Ming, Cooper Andrew I, Jones Christopher W, Lively Ryan P
School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States.
Department of Chemistry and Materials Innovation Factory, University of Liverpool, Liverpool L69 7ZD, United Kingdom.
ACS Appl Mater Interfaces. 2021 Oct 6;13(39):47118-47126. doi: 10.1021/acsami.1c12002. Epub 2021 Sep 27.
The synthesis and functionalization of porous organic cages (POCs) for separation have attracted growing interest over the past decade. However, the potential of solid-phase POCs for practical, large-scale separations will require incorporation into appropriate gas-solid or liquid-solid contactors. Contactors with more effective mass transfer properties and lower pressure drops than pelletized systems are preferred. Here, we prepared and characterized fiber sorbents with POCs throughout a cellulose acetate (CA) polymer matrix, which were then deployed in model separations. The POC CC3 was shown to be stable after exposure to spinning solvents, as confirmed by NMR, powder X-ray diffraction, and gas sorption experiments. CC3-CA fibers were spun using the dry-jet wet-quench spinning method. Spun fibers retained the adsorptive properties of CC3 powders, as confirmed by CO and N physisorption and TGA, reaching upward of 60 wt % adsorbent loading, whereas the pelletized CC3 counterparts suffered significant losses in textural properties. The separation capabilities of the CC3-CA fibers are tested with both simulated postcombustion flue gas and with Xe/Kr mixtures. Fixed bed breakthrough experiments performed on fibers samples show that CC3 embedded in polymeric fibers can effectively perform these proof-of-concept gas separations. The development of fiber sorbents embedded with POCs provides an alternative to traditional pelletization for the incorporation of these materials into adsorptive separation systems.
在过去十年中，用于分离的多孔有机笼（POC）的合成与功能化引起了越来越多的关注。然而，固相POC用于实际大规模分离的潜力将需要将其纳入合适的气固或液固接触器中。与造粒系统相比，具有更有效传质性能和更低压降的接触器是首选。在此，我们制备并表征了在醋酸纤维素（CA）聚合物基质中贯穿有POC的纤维吸附剂，然后将其用于模型分离。通过核磁共振（NMR）、粉末X射线衍射和气体吸附实验证实，POC CC3在暴露于纺丝溶剂后是稳定的。CC3-CA纤维采用干喷湿纺骤冷纺丝法纺丝。通过CO和N的物理吸附以及热重分析（TGA）证实，纺出的纤维保留了CC3粉末的吸附性能，吸附剂负载量高达60 wt%以上，而造粒的CC3对应物在结构性能上有显著损失。用模拟燃烧后烟道气和Xe/Kr混合物测试了CC3-CA纤维的分离能力。对纤维样品进行的固定床穿透实验表明，嵌入聚合物纤维中的CC3能够有效地进行这些概念验证气体分离。嵌入POC的纤维吸附剂的开发为将这些材料纳入吸附分离系统提供了一种替代传统造粒的方法。
