Modeling of Adsorption of Light Mercaptans from Natural Gas using Pore Network Model

The usage of the pore network model is growing in simulation of solid-liquid processes such as catalytic processes, filtration and adsorption. In this kind of simulations unlike the continuous methods, the exact information of effective diffusivity and tortuosity factor is achieved. In pore network model, the porous media structure is considered as a three dimensional regular network which is composed of nodes and these nodes connect to each other by some pores. In this thesis by investigating the adsorption of light mercaptans on Activated Carbon in a three dimensional network, diffusivity and tortuosity factors are achieved according to Knudsen diffusion, viscous flow and surface diffusion conditions. In adsorption volume of pores of sorbent are reduced and this reduction affects on the permeability of adsorbed phase. Therefore in this modeling, the effect of the pore volume reduction on the cross section area of pores has been considered. So it was observed that the predicted results show better agreement to the experimental data. The result shows that if the amount of adsorption be small, we can neglect the variation of effective diffusivity (till saturation) with time and place.