Modeling of unsteady-state permeation of gas mixture through a self-synthesized PDMS membranes

▶ Unsteady state permeation of ternary gas mixture of H2, CH4 and C3H8 through PDMS membrane was simulated at different operating conditions. ▶ Frisch method was used to derive the time lag for direct determination of diffusion coefficients in a concentration dependent system. ▶ Comparison between mixed and single gas permeation properties and effect of cross-linker concentration was carried out. ▶ It was confirmed that diffusivity is the effective parameter on permeability of lighter gases, while solubility is the prevailing factor on permeability of heavier gas.