Breaking the trade-off between selectivity and adsorption capacity for gas separation

Naveen Kumar; Soumya Mukherjee; Nathan C Harvey-Reid; Andrey A Bezrukov; Kui Tan; Vinicius Martins; Matthias Vandichel; Tony Pham; Lisa M van Wyk; Kolade Oyekan; Amrit Kumar; Katherine A Forrest; Komal M Patil; Leonard J Barbour; Brian Space; Yining Huang; Paul E Kruger; Michael J Zaworotko

doi:10.1016/j.chempr.2021.07.007

Breaking the trade-off between selectivity and adsorption capacity for gas separation

Chem. 2021 Nov 11;7(11):3085-3098. doi: 10.1016/j.chempr.2021.07.007.

Authors

Naveen Kumar¹, Soumya Mukherjee¹, Nathan C Harvey-Reid², Andrey A Bezrukov¹, Kui Tan³, Vinicius Martins⁴, Matthias Vandichel¹, Tony Pham⁵, Lisa M van Wyk⁶, Kolade Oyekan³, Amrit Kumar¹, Katherine A Forrest⁵, Komal M Patil², Leonard J Barbour⁶, Brian Space⁵, Yining Huang⁴, Paul E Kruger², Michael J Zaworotko¹

Affiliations

¹ Bernal Institute, Department of Chemical Sciences, University of Limerick, Limerick V94 T9PX, Republic of Ireland.
² MacDiarmid Institute for Advanced Materials and Nanotechnology, School of Physical and Chemical Sciences, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand.
³ Department of Materials Science & Engineering, University of Texas at Dallas, Richardson, TX 75080, USA.
⁴ Department of Chemistry, the University of Western Ontario, 1151 Richmond Street, London, ON N6A 5B7, Canada.
⁵ Department of Chemistry, University of South Florida, 4202 East Fowler Avenue, CHE205, Tampa, FL 33620-5250, USA.
⁶ Department of Chemistry and Polymer Science, University of Stellenbosch, Stellenbosch, Matieland 7602, South Africa.

Abstract

The trade-off between selectivity and adsorption capacity with porous materials is a major roadblock to reducing the energy footprint of gas separation technologies. To address this matter, we report herein a systematic crystal engineering study of C₂H₂ removal from CO₂ in a family of hybrid ultramicroporous materials (HUMs). The HUMs are composed of the same organic linker ligand, 4-(3,5-dimethyl-1H-pyrazol-4-yl)pyridine, pypz, three inorganic pillar ligands, and two metal cations, thereby affording six isostructural pcu topology HUMs. All six HUMs exhibited strong binding sites for C₂H₂ and weaker affinity for CO₂. The tuning of pore size and chemistry enabled by crystal engineering resulted in benchmark C₂H₂/CO₂ separation performance. Fixed-bed dynamic column breakthrough experiments for an equimolar (v/v = 1:1) C₂H₂/CO₂ binary gas mixture revealed that one sorbent, SIFSIX-21-Ni, was the first C₂H₂ selective sorbent that combines exceptional separation selectivity (27.7) with high adsorption capacity (4 mmol·g^-1).

Keywords: acetylene; carbon dioxide; crystal engineering; gas purification; gas separation; hybrid ultramicroporous material; physisorbent; porous materials; selectivity.