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

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 CO2 absorption due to the advantages over traditional contacting devices. However, in spite of their important 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 by incorporation of superhydrophobic silica nanoparticles; CH3SiO2, synthesized via sol–gel method on the surface and the cross section of the membrane. In order to study the effect of the hydrophobic agent on the water repellent properties of the silica nanoparticles, (MTES/TEOS) molar ratio was varied from 1 to 5. The composite hollow fiber membranes were characterized by FTIR, FE-SEM and contact angle analysis. The experimental results revealed that the best hydrophobic membrane showed a water contact angle of 168◦.The CO2 absorption flux of the composite hollow fiber membranes was investigated in a gas–liquid membrane contactor system. The chemical compatibility test indicated that after the long-term constant contact with the 30 wt% of aqueous monoethanolamine (MEA), the hydrophobicity of the composite membrane still maintained and was much higher than that of neat PP membrane.