Selective Ethane/Ethylene Separation in a Robust Microporous Hydrogen-Bonded Organic Framework
Year: 2019
Type: article
Abstract: The separation of ethane (C 2 H 6 ) from ethylene (C 2 H 4 ) is of prime importance in the production of polymer-grade C 2 H 4 for industrial manufacturing. It is very challenging and still remains unexploited to fully realize efficient C 2 H 6 /C 2 H 4 separation in the emerging hydrogen-bonded organic frameworks (HOFs) due to the weak nature of hydrogen bonds. We herein report the benchmark example of a novel ultrarobust HOF adsorbent (termed as HOF-76a) with a Brunauer–Emmett–Teller surface area exceeding 1100 m 2 g –1, exhibiting the preferential binding of C 2 H 6 over C 2 H 4 and thus highly selective separation of C 2 H 6 /C 2 H 4 . Theoretical calculations indicate the key role of the nonpolar surface and the suitable triangular channel-like pores in HOF-76a to sterically “match” better with the nonplanar C 2 H 6 molecule than the planar C 2 H 4, thus affording overall stronger multipoint van der Waals interactions with C 2 H 6 . The exceptional separation performance of HOF-76a for C 2 H 6 /C 2 H 4 separation was clearly demonstrated by gas adsorption isotherms, ideal adsorbed solution theory calculations, and simulated and experimental breakthrough curves. Breakthrough experiments on HOF-76a reveal that polymer-grade ethylene gas can be straightforwardly produced from 50/50 (v/v) C 2 H 6 /C 2 H 4 mixtures during the first adsorption cycle with a high productivity of 7.2 L/kg at 298 K and 1.01 bar and 18.8 L/kg at 298 K and 5.0 bar, respectively.
DOI: 10.1021/jacs.9b12428
Institutions: Chinese Academy of Sciences, Fujian Institute of Research on the Structure of Matter, State Key Laboratory of Structural Chemistry, State Key Laboratory of Silicon Materials, Zhejiang University, The University of Texas at San Antonio, Taiyuan University of Technology, Zhejiang University of Technology, University of Amsterdam, National Institute of Standards and Technology, NIST Center for Neutron Research
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2995856058