Selective gas capture via kinetic trapping. Issue 31 (20th July 2016)

• Record Type: Journal Article
• Authors: Kundu, Joyjit; Pascal, Tod; Prendergast, David; Whitelam, Stephen
• Is Part Of: Physical chemistry chemical physics. Volume 18:Issue 31(2016)
• Page Start: 21760
• Page End: 21766
• Publication Date: 2016-07-20
• Subjects: Chemistry, Physical and theoretical -- Periodicals; 541.3
• DOI: 10.1039/c6cp03940e
• Languages: English
• ISSNs: 1463-9076

Abstract

Abstract : We studied the dynamics of gas capture in a simulation-model of a porous framework. We found that relaxing the requirement of equilibrium substantially increases the parameter space of conditions and materials for which selective gas capture can be achieved. Abstract : Conventional approaches to the capture of CO2 by metal–organic frameworks focus on equilibrium conditions, and frameworks that contain little CO2 in equilibrium are often rejected as carbon-capture materials. Here we use a statistical mechanical model, parameterized by quantum mechanical data, to suggest that metal–organic frameworks can be used to separate CO2 from a typical flue gas mixture when used under nonequilibrium conditions. The origin of this selectivity is an emergent gas-separation mechanism that results from the acquisition by different gas types of different mobilities within a crowded framework. The resulting distribution of gas types within the framework is in general spatially and dynamically heterogeneous. Our results suggest that relaxing the requirement of equilibrium can substantially increase the parameter space of conditions and materials for which selective gas capture can be effected.