Benchmarking selective capture of trace CO2 from C2H2 using an amine-functionalized adsorbent

• Published in: Nature communications Vol. 16; no. 1; pp. 2598 - 11
• Main Authors: Zou, Jin-Sheng, Wang, Zhi-Peng, Andaloussi, Yassin H., Xue, Jiapeng, Zhang, Wanli, Lucier, Bryan E. G., Zhang, Zeyang, Jia, Yanan, Wu, Xue-Cui, Li, Jiahan, Huang, Yining, Zaworotko, Michael J., Chen, Guangjin, Chen, Shoushun, Peng, Yun-Lei
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 16.03.2025; Nature Publishing Group; Nature Portfolio
• Subjects: 639/301/357/1018; 639/638/298/923/1028; 639/638/455/958; Adsorbents; Adsorption; Carbon dioxide; Chemisorption; Density functional theory; Fourier transforms; Humanities and Social Sciences; Infrared spectroscopy; multidisciplinary; NMR; Nuclear magnetic resonance; Physical properties; Polyetherimides; Polyethyleneimine; Resins; Science; Science (multidisciplinary); Selectivity
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-025-57972-7

Purifying C 2 H 2 by removing trace CO 2 is critically needed yet challenged by their analogous physical properties. Herein, we report a commercial resin adsorbent HP20 (Diaion® HP-20 Resin) loaded with polyethyleneimine (PEI@HP20) which selectively captures trace CO 2 and excludes C 2 H 2 . PEI@HP20 possesses a high CO 2 adsorption capacity (4.35 mmol/g) at 100 kPa and 298 K and a record CO 2 /C 2 H 2 uptake ratio compared with all reported CO 2 -selective adsorbents. The ideal adsorbed solution theory selectivity reaches 1.33×10 7 . The pilot-scale pressure-temperature swing adsorption on 2 kg PEI@HP20 further validated that it can obtain >99.99% purity C 2 H 2 from CO 2 /C 2 H 2 (1/99, v/v) mixtures with a high yield of 344.7 g per cycle. The combination of multinuclear solid-state Nuclear Magnetic Resonance, Fourier Transform infrared spectroscopy and density functional theory calculations reveal that the performance of PEI@HP20 relies on a dual chemisorption/physisorption mechanism. This work highlights a promising method to develop green, low cost, high efficiency, and readily scalable CO 2 -selective adsorbent. Purifying C 2 H 2 by removing trace CO 2 is needed but challenging due to their analogous physical properties. Herein, the authors report the pilot-scale production of a commercial resin adsorbent loaded with polyethyleneimine for the selective capture of CO 2 traces and exclusion of C 2 H 2 .