Highly productive C3H4/C3H6 trace separation by a packing polymorph of a layered hybrid ultramicroporous material

DOI: 10.1021/jacs.3c03505

Authors: Mei-Yan Gao (University of Limerick) , Andrey A. Bezrukov (University of Limerick) , Bai-Qiao Song (University of Limerick) , Meng He (University of Manchester) , Sousa Javan Nikkhah (University of Limerick) , Shi-Qiang Wang (Institute of Materials Research and Engineering (IMRE), Agency for Science, Technology and Research (A*STAR)) , Naveen Kumar (University of Limerick) , Shaza Darwish (University of Limerick) , Debobroto Sensharma (University of Limerick) , Chenghua Deng (University of Limerick) , Jiangnan Li (University of Manchester) , Lunjie Liu (Southern University of Science and Technology) , Rajamani Krishna (University of Amsterdam) , Matthias Vandichel (University of Limerick) , Sihai Yang (University of Manchester,) , Michael J. Zaworotko (University of Limerick)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Journal Of The American Chemical Society

State: Published (Approved)
Published: May 2023

Abstract: Ultramicroporous materials can be highly effective at trace gas separations when they offer a high density of selective binding sites. Herein, we report that sql-NbOFFIVE-bpe-Cu, a new variant of a previously reported ultramicroporous square lattice, sql, topology material, sql-SIFSIX-bpe-Zn, can exist in two polymorphs. These polymorphs, sql-NbOFFIVE-bpe-Cu-AA (AA) and sql-NbOFFIVE-bpe-Cu-AB (AB), exhibit AAAA and ABAB packing of the sql layers, respectively. Whereas NbOFFIVE-bpe-Cu-AA (AA) is isostructural with sql-SIFSIX-bpe-Zn, each exhibiting intrinsic 1D channels, sql-NbOFFIVE-bpe-Cu-AB (AB) has two types of channels, the intrinsic channels and extrinsic channels between the sql networks. Gas and temperature induced transformations of the two polymorphs of sql-NbOFFIVE-bpe-Cu were investigated by pure gas sorption, single-crystal X-ray diffraction (SCXRD), variable temperature powder X-ray diffraction (VT-PXRD), and synchrotron PXRD. We observed that the extrinsic pore structure of AB resulted in properties with potential for selective C3H4/C3H6 separation. Subsequent dynamic gas breakthrough measurements revealed exceptional experimental C3H4/C3H6 selectivity (270) and a new benchmark for productivity (118 mmol g–1) of polymer grade C3H6 (purity >99.99%) from a 1:99 C3H4/C3H6 mixture. Structural analysis, gas sorption studies, and gas adsorption kinetics enabled us to determine that a binding “sweet spot” for C3H4 in the extrinsic pores is behind the benchmark separation performance. Density-functional theory (DFT) calculations and Canonical Monte Carlo (CMC) simulations provided further insight into the binding sites of C3H4 and C3H6 molecules within these two hybrid ultramicroporous materials, HUMs. These results highlight, to our knowledge for the first time, how pore engineering through the study of packing polymorphism in layered materials can dramatically change the separation performance of a physisorbent.

Diamond Keywords: Gas Separation

Subject Areas: Materials, Chemistry


Instruments: I19-Small Molecule Single Crystal Diffraction

Other Facilities: ID22 at ESRF

Added On: 20/05/2023 17:08

Documents:
jacs.3c03505.pdf

Discipline Tags:

Chemistry Materials Science Chemical Engineering Engineering & Technology Organometallic Chemistry

Technical Tags:

Diffraction Single Crystal X-ray Diffraction (SXRD)