We have been using molecular simulations to evaluate the performance of polymeric membranes for gas separations. We have developed molecular models for polymeric membranes for separation of CO2 from natural gas streams. One of the challenges in both experiments and simulations is to obtain accurate values of the gas diffusion coefficients in the polymer matrix. We have recently shown that incorporating mixture self-diffusivities alters the membrane permeability, predicting improved performance of the membrane when compared with pure component diffusivity data that is routinely used to assess membrane performance. This project will involve carrying out molecular dynamics simulations and kinetic Monte Carlo simulations to obtain diffusivities of different gas mixtures to predict the perm selectivity, of microporous materials used for gas separations in the chemical industry. These include polymers, zeolites, metalorganic frameworks. These materials are used widely in the chemical industry and the project will give molecular insights into the accurate assessment of materials for developing novel gas separation technologies for CO2 capture for coal combustion as well as direct air capture technologies.
