Axial Distribution of Permeance and Selectivity of a Porous Cylindrical Tube for Binary Gas Mixtures (CO2/N2)

Abstract

In previous studies, the selectivity property of a porous stainless steel cylindrical tube showed different filtration rates of pure carbon dioxide (CO2) and of pure nitrogen (N2) because of the effect of the dynamic boundary layer into the tube. In this study, a binary mixture of CO2 and N2 is considered under three different volumetric compositions (50/50%, 60/40%, and 70/30%) to evaluate the separation property of a porous stainless steel tube (membrane effect). The pure gas permeability, mixture permeability, ideal selectivity, and separation selectivity of this tube are determined for a total mass flow rate ranging from 1 to 2.5 g·s–1 and for an inlet pressure varying from 2 to 3.5 bar accordingly. The factors affecting the distribution of CO2 and N2 inside the porous tube are qualified. It is found that both the ideal and separation selectivity values are close to each other for a 50/50% composition, but the difference between the values increases for different compositions because of the effects of...