Screening CO2/N2 selectivity in metal-organic frameworks using Monte Carlo simulations and ideal adsorbed solution theory

Selective adsorption of CO2 over N2 is important in the design and selection of adsorbents such as metal-organic frameworks (MOFs) for CO2 capture and sequestration. In this work, single-component and mixture adsorption isotherms were calculated in MOFs using grand canonical Monte Carlo (GCMC) simulations at conditions relevant for CO2 capture from flue gas. Mixture results predicted from single-component isotherms plus ideal adsorbed solution theory (IAST) agree well with those calculated from full GCMC mixture simulations. This suggests that IAST can be used for preliminary screening of MOFs for CO2 capture as an alternative to more time-consuming mixture simulations or experiments. (C) 2011 Canadian Society for Chemical Engineering