Yan Boning, Xu Kang, Cao Yucai, Xu Xueru, Lei Ming
Department of Chemistry, Zhejiang University, Hangzhou, 310058, P. R. China.
State Key Laboratory of Polyolefins and Catalysis, Shanghai Key Laboratory of Catalysis Technology for Polyolefins, Shanghai Research Institute of Chemical Industry Company Ltd., Shanghai, 200062, China.
Small. 2024 Dec;20(52):e2407842. doi: 10.1002/smll.202407842. Epub 2024 Oct 20.
Developing high-performance adsorbents for energy-efficient separation of xylene isomers has important research and application value. Identification and separation of xylene isomers (PX, MX, and OX) at room temperature based on the different relative positions of two methyl groups on the benzene ring is an unprecedented attempt. Herein, 1-aminopyrene polymer (PAP) is designed and electro-synthesized composited with a supporting electrolyte as an adsorbent for the separation of xylene isomers using a multi-stage dispersed liquid-solid adsorption process at room temperature. Each -NH-pyrene-NH- unit can form a force field to identify and discriminate xylene isomer through π-π interaction combined with -CH···-NH- interactions of different strength, thereby achieving separation of PX, MX, and OX isomers by amplifying the slight differences in the adsorption capacity and diffusion rates. The density functional theory (DFT) simulations provide a more quantitative analysis of the adsorbate-adsorbent interactions to illustrate PX > MX > OX order of adsorption selectivity. This study may offer an alternative strategy for the precise designing of energy-efficient and adsorption-based separation materials.
开发用于高效分离二甲苯异构体的高性能吸附剂具有重要的研究和应用价值。基于苯环上两个甲基的不同相对位置在室温下鉴定和分离二甲苯异构体（对二甲苯、间二甲苯和邻二甲苯）是一次前所未有的尝试。在此，设计并电合成了1-氨基芘聚合物（PAP），并将其与支持电解质复合，作为一种吸附剂，用于在室温下通过多级分散液-固吸附过程分离二甲苯异构体。每个-NH-芘-NH-单元可形成一个力场，通过π-π相互作用结合不同强度的-CH···-NH-相互作用来识别和区分二甲苯异构体，从而通过放大吸附容量和扩散速率的微小差异实现对二甲苯、间二甲苯和邻二甲苯异构体的分离。密度泛函理论（DFT）模拟为吸附质与吸附剂之间的相互作用提供了更定量的分析，以说明吸附选择性的顺序为对二甲苯>间二甲苯>邻二甲苯。该研究可能为精确设计节能型和基于吸附的分离材料提供一种替代策略。
