Atomically detailed modeling of metal organic frameworks for adsorption, diffusion, and separation of noble gas mixtures

Abstract

Atomically detailed simulations have been widely used to assess gas storage and gas separation properties of metal organic frameworks (MOFs). We used molecular simulations to examine adsorption, diffusion, and separation of noble gas mixtures in MOFs. Adsorption isotherms and self-diffusivities of Xe/Kr and Xe/Ar mixtures at various compositions in ten representative MOFs were computed using grand canonical Monte Carlo and equilibrium molecular dynamics simulations. Several properties of MOFs such as adsorption selectivity, working capacity, diffusion selectivity, permeation selectivity, and gas permeability were evaluated and compared with those of traditional nanoporous materials. Results showed that MOFs are promising candidates for Xe/Kr and Xe/Ar separations due to their high Xe selectivity and permeability.