A Complete Transport Validated Model on a Zeolite Membrane for Carbon Dioxide Permeance and Capture

Abstract

The CO2 emissions from major industries cause serious global environment problems and their mitigation is urgently needed. The use of zeolite membranes is a very efficient way in order to capture CO2 from some flue gases. The dominant transport mechanism at low temperature andor high pressure is the diffusion through the membrane. This procedure can be divided in three steps: Adsorption of the molecules of the species in the surface of the membrane, then a driving force gives a path where the species follow inside the membrane and finally the species desorbed from the surface of the membrane. The current work is aimed at developing a simulation model for the CO2 transport through a zeolite membrane and estimate the diffusion phenomenon through a very thin membrane of 150 nm in a Wicke-Kallenbach cell. The cell is cylindrical in shape with diameter of 19 mm and consists of a retentate gas chamber, a permeate gas chamber which are separated by a cylindrical zeolite membrane. This apparatus have been modeled with Comsol Multiphysics software. The gas chosen to insert in the retentate gas chamber is CO2 and the inert gas is Argon. The Maxwell-Stefan surface equations used in order to calculate the velocity gradients inside the zeolite membrane and in order to solve the velocity profile within the permeate and retentate gas chamber, the incompressible Navier-Stokes equations were solved. Finally, the mass balance equation for both gases solved with the mass balance differential equations. Validation of our model has been obtained at low and high temperatures suggesting that higher the temperature the better the results.