Molecular modeling of MOF and ZIF-filled MMMs for CO₂/N₂ separations

In this study, gas permeability and selectivity of metal organic framework and zeolite imidazolate framework-filled mixed matrix membranes (MOF and ZIF-filled MMMs) were predicted using atomically detailed simulations and continuum modeling methods for CO₂/N₂ separations. The accuracy of the computational methods was validated by comparing the gas permeability and selectivity of several MOF and ZIF-filled MMMs with the available experimental data. After the good agreement between experiments and computational predictions was shown, this approach was used to estimate the separation performances of several new MMMs composed of various polymers and ZIFs. Effects of framework flexibility of the filler particles, filler loading and operation temperature on the CO₂/N₂ separation performance of MMMs were examined. CO₂/N₂ separation performances of MMMs composed of two different types of fillers and MMMs composed of two different types of polymers were also studied. Results showed that there are several promising MOF and ZIF-filled MMMs that can achieve CO₂/N₂ separation with high CO₂ selectivity.