Fabrication of hydrophobic PP/CH3SiO2 composite hollow fiber membrane for membrane contactor application

Polymeric membrane wetting by liquid absorbent is one of the major challenges of the gas- liquid membrane contactors. In order to overcome this issue, composite polypropylene (PP) hollow fiber membranes were prepared by incorporation of methyl grafted silica nanoparticles (CH3-g-silica NPs) via two treatment approaches including blending the NPs with dope solution before membrane fabricating (approach 1), and also coating the NPs on the surface of the prepared membrane (approach 2). The fabricated membranes were characterized by using ATR-FTIR, FESEM, TEM, AFM, porosity, contact angle, mechanical strength, breakthrough pressure, wetting resistance and gas permeation test. The obtained results from ATR-FTIR spectra confirmed the successful formation of the PP-CH3SiO2 composite hollow fiber membranes. It was seen that for composite membranes fabricated with approaches 1 and 2 the average contact angle increased from 124 degrees to 145 degrees and 168 degrees, respectively. The fabricated membranes were also investigated for CO2 absorption process in gas- liquid membrane contactors. As a result, the gentle decrease in flux of composite membranes compare to the sharp flux drop of neat one confirmed the effective improvement in the non-wetting property of the membranes in the presence of inorganic particles.