Wang Yao-Ting, McHale Corie, Wang Xiqu, Chang Chung-Kai, Chuang Yu-Chun, Kaveevivitchai Watchareeya, Miljanić Ognjen Š, Chen Teng-Hao
School of Pharmacy, National Cheng Kung University, No.1, University Rd., Tainan City, 70101, Taiwan.
Department of Chemical Engineering and Hierarchical Green-Energy Materials Research Center, National Cheng Kung University, No.1, University Rd., Tainan City, 70101, Taiwan.
Angew Chem Int Ed Engl. 2021 Jun 25;60(27):14931-14937. doi: 10.1002/anie.202102813. Epub 2021 May 5.
A porous molecular crystal (PMC) assembled by macrocyclic cyclotetrabenzoin acetate is an efficient adsorbent for CO separations. The 7.1×7.1 Å square pore of PMC and its ester C=O groups play important roles in improving its affinity for CO molecules. The benzene walls of macrocycle engage in an apparent [π⋅⋅⋅π] interaction with the molecule of CO at low pressure. In addition, the polar carbonyl groups pointing inward the square channels reduce the size of aperture to a 5.0×5.0 Å square, which offers kinetic selectivity for CO capture. The PMC features water tolerance and high structural stability under vacuum and various gas adsorption conditions, which are rare among intrinsically porous organic molecules. Most importantly, the moderate adsorbate-adsorbent interaction allows the PMC to be readily regenerated, and therefore applied to pressure swing adsorption processes. The eluted N and CH are obtained with over 99.9 % and 99.8 % purity, respectively, and the separation performance is stable for 30 cycles. Coupled with its easy synthesis, cyclotetrabenzoin acetate is a promising adsorbent for CO separations from flue and natural gases.
由大环环四苯甲酸酯组装而成的多孔分子晶体（PMC）是一种用于CO分离的高效吸附剂。PMC的7.1×7.1 Å方形孔及其酯基C=O基团在提高其对CO分子的亲和力方面发挥着重要作用。大环的苯壁在低压下与CO分子发生明显的[π⋅⋅⋅π]相互作用。此外，指向方形通道内部的极性羰基将孔径减小到5.0×5.0 Å的正方形，这为CO捕获提供了动力学选择性。PMC具有耐水性，在真空和各种气体吸附条件下具有高结构稳定性，这在本征多孔有机分子中很少见。最重要的是，适度的吸附质-吸附剂相互作用使PMC易于再生，因此可应用于变压吸附过程。洗脱得到纯度分别超过99.9%和99.8%的N和CH，并且分离性能在30个循环中保持稳定。结合其易于合成的特点，环四苯甲酸酯是一种从烟道气和天然气中分离CO的有前景的吸附剂。
