Microporous membrane absorbers were used for separation of carbon dioxide and nitrogen mixture. The membrane was made of either polysulfone(PS) or polytetrafluoroethylene(PTFE) and the absorbents were distilled water and monoetanol amine(MEA)/water solution. The results showed that the hydrophilicity of the membrane materials was a very important factor in determining the separation efficiency and rather hydrophobic PTFE membrane exhibited better performance due to its hindrance to the absorbent wettability. Considering the separation efficiency alone, the chemical absorbent MEA was better than the physical absorbent water. Among the practically important features of the present results was that the removal rate of carbon dioxide was increased with the volume flow rate of an absorbent and saturated at a certain value. Finally, the theoretical predictions by the model for mass transport through the membrane absorber agreed reasonably well with the experimental results.