Simulation of transport phenomena in capture of from air was carried out in this work. Separation of as an air pollutant from nitrogen using porous membranes is simulated to optimize the process. Computational fluid dynamics approach is utilized for numerical simulation of process aiming to predict the concentration of in the membrane module. 2-Amino-2-methyl-1-propanol as chemical absorbent was considered in the simulations. Hydrodynamics and mass transfer of system were investigated by the developed numerical procedure. The simulation results were validated through comparing with experimental data, and good agreement was achieved. The simulation results revealed that removal rate increases with an enhancement of absorbent flow rate, and decreases with the increasing gas flow rate. This simulation procedure can predict capture from air using porous membranes.