A novel method for incorporating hydrophobic silica nanoparticles on the polypropylene membranes for CO2 absorption in a membrane contactor

Gas–liquid hollow fiber membrane contactor can be a promising alternative for the CO2absorption due to the advantages over traditional contacting devices. However, in spite of theirimportant advantages, such systems suffer from wetting of porous membranes with liquid absorbents.To overcome this problem, non-wetting polypropylene (PP) hollow fiber membrane was prepared byincorporation of superhydrophobic silica nanoparticles; CH3SiO2, synthesized via sol–gel method onthe surface and the cross section of the membrane. In order to study the effect of the hydrophobic agenton the water repellent properties of the silica nanoparticles, (MTES/TEOS) molar ratio was variedfrom 1 to 5. The composite hollow fiber membranes were characterized by FTIR, FE-SEM and contactangle analysis. The experimental results revealed that the best hydrophobic membrane showed a watercontact angle of 168◦.The CO2 absorption flux of the composite hollow fiber membranes was investigated in a gas–liquidmembrane contactor system. The chemical compatibility test indicated that after the long-term constantcontact with the 30 wt% of aqueous monoethanolamine (MEA), the hydrophobicity of the compositemembrane still maintained and was much higher than that of neat PP membrane.

Keywords:

CO(2) absorption , silica nanoparticles , membrane contactor