Thermodynamic and kinetic prospects in the modeling of gas phase adsorption processes

The main scope of this work is to examine and evaluate the roles of different aspects of adsorption science and technology (namely, the roles of the characteristics of the adsorbents, properties of the adsorbed molecules, interactions between the surface of the adsorbent and the adsorbed molecules, and among each of the adsorbed molecules and the others, thermodynamic properties of the adsorbed phase, and non-equilibrium dynamic behavior of the adsorption phenomenon) on the proper description of the adsorption phenomenon and prediction of the adsorption process behaviors.; The results from this work have collectively indicated the importance of accounting for the variations of the equilibrium and dynamic properties of the adsorbed phase with the process operating conditions, especially under the conditions resulting in high adsorption affinities. Some of those conditions include the high interactions between the adsorbed phase and surface of the adsorbent and low temperatures. The role of interactions between the surface of the adsorbent and the adsorbed molecules (presented in various forms such as the surface heterogeneity, the extent of localization of the adsorbed molecules, and the partition functions arising as a result of adsorption) was proven to be one of the most important reasons behind the variation of the derived thermodynamic properties of the adsorbed phase (namely, the isosteric heat of adsorption) with temperature. The lateral interactions among the adsorbed molecules have significant effects on the adsorption equilibria and on the variation of the derived thermodynamic properties with the fractional surface coverage of the adsorbent. Nevertheless, they had almost no effect on their variations with temperature. The proper description of the mass transfer resistances within the adsorbed phase as a function of the process operating conditions (namely, the temperature and the loading of the adsorbed molecules) was also proven to be very significant for the accurate prediction of the pressure swing adsorption process behavior.