Molecular simulations of separation of gas mixtures using zeolite membranes

The main obstacles to the membrane separation of gas mixture such as air continue to be lower selectivity and less productivity. To improve the performance a better understanding of the molecular level forces between the competing gas molecules and the membrane surfaces, which are ultimately responsible for these separations is required. The main objective of this dissertation is to improve fundamental molecular level understanding of the molecular transport processes in such membranes. This will contribute to more efficient design of such processes.; Gas separations with three different zeolite membranes, Faujasite, MFI and Chabazite, have been examined using the method of molecular dynamics. Two binary mixtures are investigated, oxygen/nitrogen and nitrogen/carbon dioxide. These mixtures have been found experimentally to exhibit contrasting behavior when pure gas and mixture permeation rates are compared. Our simulation results were found to replicate this experimental behavior. By examining the loading of the membranes and the diffusion rates inside the zeolites, we have been able to explain such contrasting behavior of oxygen/nitrogen and nitrogen/carbon dioxide mixtures.; We also report a preliminary study of adsorption of hydrocarbons on zeolite membranes, which can benefit gas separation study by improving the understanding of the adsorption property of zeolites.