文献类型：期刊文献

英文题名：Precise acidity tuning in ion-exchanged FAU zeolites for enhanced selective adsorption and room-temperature desorption of C2/C3 olefins

作者：Li, Peicheng[1];Jiang, Hao[1];Gao, Wenhao[1];Wang, Yifan[1];Zhou, Yousheng[1];Zhao, Qiyue[1];Liu, Chuanlei[1];Wu, Qiumin[1];Shen, Benxian[1];Sun, Hui[1,2]

机构：[1]East China Univ Sci & Technol, Sch Chem Engn, Shanghai 200237, Peoples R China;[2]Xinjiang Univ, Sch Chem Engn & Technol, Minist Key Lab Oil & Gas Fine Chem, Urumqi 830046, Peoples R China

年份：2025

卷号：376

外文期刊名：SEPARATION AND PURIFICATION TECHNOLOGY

收录：;EI(收录号：20252518627017);WOS:【SCI-EXPANDED(收录号:WOS:001537876200012)】；

基金：This work is financially supported by Key R & D Project in Xinjiang Uygur Autonomous Region (2024B01018) and the National Natural Science Foundation of China (Grant 21878097 and 22178109) .

语种：英文

外文关键词：Ion-exchange; Pyridine; Acid sites; Desorption; C3H6; C2H4; Ion-exchange; Pyridine; Acid sites; Desorption

摘要：The separation of high-purity olefins from light olefin/alkane mixtures is crucial for industrial applications. Metal ion-exchanged zeolites are effective adsorbents, but their strong host-guest interactions often hinder desorption at ambient temperatures. Herein, adsorption site acidity in zeolites is precisely tuned to enhance weak acid sites while preventing irreversible strong acid sites. Ion-exchange modified Li-Y, a C3H6-selective adsorbent with a breakthrough capacity of 2.02 mmol/g, is fully regenerable at room temperature. Using a tandem bed process with Li-Y and Ag/Cd-4A, we successfully separated C2H4 and C3H6 from a C2H4/C2H6/C3H6/C3H8 mixture, achieving > 99 % purities of both C2H4 and C3H6 products. Increased ionic potential enhances adsorption, but excessive potential generates strong Bronsted acid sites (BAS), promoting olefin polymerization. To mitigate this, we proposed a strategy using pyridine to selectively shield these strong BAS, thereby restoring the desorption performance of metal ion-exchanged zeolites. Current study offers an approach to designing promising adsorbents that maintain high performance across multiple cycles with minimal energy input, paving the way for sustainable olefin/alkane separation processes.