[Separation of carbon dioxide from gas mixture by membrane contactor]

In this paper, membrane contactor made of hydrophobic hollow fiber polypropylene porous membrane (HFPPM) was used for separating carbon dioxide (CO2) from CO2/N2 mixtures. The effects of absorbents, concentration and flow rate of feeding gas and absorbent solution, lumen/shell side processes and gas permeability of HFPPM(P) on the CO2 absorption efficiency were investigated. It was found that the absorption efficiency of three absorbents ranged in order of ethanolamine > sodium hydroxide > diethanol amine. For CO2/N2 mixture of c(in) = 20% and v(in) = 0.5-1.0 m3.h-1, and MEA solution of cMEA = 2.5 mol.L-1 and vL = 40-160 L.h-1, the removal efficiencies of CO2 (eta) and the mass transport coefficients (K) was 9.5% - 99.5% and 4.5-6.8 x 10(-4) m.s.-1 respectively. K of the modules made of HFPPM with larger P was relatively larger. eta in lumen process was 30% larger than that in shell process.