Separation of CO₂ from the gas mixture was performed by a module with the hydrophobic PP(polypropy lene) microporous membrane and using the deion water.Effects of gas and liquid flowrates,CO₂ concentration and operation temperatures as well as membrane configuration on overall mass transfer coefficient were investigated.A mathematical model was presented by correlating the resistance in series and the mass differential equation.Mass transfer was simulated under the various operation conditions.Results show that the change of hydrodynamics in the module can enhance mass transfer finitely.Overall mass transfer coefficient can be increased with the increase of CO₂ concentration.Membrane modules with high porosity possess a high mass transfer coefficient.Elevation of operation temperatures can accelerate the diffusion and enhance the mass transfer.Partial micropores may be wetted at higher operation temperatures.The operation process of hydrophobic hollow fiber membrane module can be better simulated by the model.The modeling results are in good agreement with experiments.