(447u) MOF-Based Mixed Matrix Membranes for CO2/N2 Separations

Development of new membrane materials for separation of CO₂ from N₂ is crucial for the mitigation of CO₂ emissions. In this study, CO₂/N₂ separation potential of metal organic framework (MOF)-based mixed matrix membranes (MMMs) were investigated. We first performed atomically-detailed simulations to obtain adsorption data of CO₂ and N₂ gases in MOFs using Grand Canonical Monte Carlo (GCMC) simulations. Then Molecular Dynamics (MD) simulations were performed in order to predict diffusion properties of gases in MOFs. Simulation results were used to obtain CO₂ and N₂ permeabilities of MOFs. A large number of MOFs was found to be located above the upper bound established for polymeric membranesâ?? CO₂/N₂ separation performances. We then combined the results of our simulations for MOFs with the experimentally available data of gas permeability of polymers to predict permeability MOF-based MMMs. Gas permeability and selectivity of 700 new MMMs composed of 70 different MOFs and 10 different polymers were calculated for CO₂/N₂ separation. Several MOF-based MMMs were able to exceed the upper bound established for CO₂/N₂ separation. Results showed that for polymers with low CO₂ permeability but high CO₂ selectivity, the identity of the MOF filler is not important while for polymers that have high CO₂ permeabilities but low CO₂ selectivities, selection of the MOF strongly affects the separation properties of the MMMs. We believe that our results will guide both experimental and computational studies in order to find the best performing MOF/polymer MMMs for CO₂/N₂ separations.

Acknowledgement: Financial support provided by The Scientific and Technological Research Council of Turkey (TUBITAK) Grant MAG-213M401 is gratefully acknowledged.