A novel surface modified polyetherimide hollow fiber membrane for gas–liquid contacting processes

A novel surface modified polyetherimide (PEI) hollow fiber membrane was fabricated via dry–wet phased inversion process where the spinning dope contains Surface Modifying Macromolecule (SMM). The surface modified membrane exhibited large pore size, higher effective surface porosity, contact angle and porosity but lower Liquid Entry Pressure of water compared to polyetherimide hollow fiber membrane without SMM.The performance of surface modified membrane in contactor application for gas separation process was evaluated based on CO2 absorption process using water as absorbent and pure CO2 and 20:80 CO2/CH4 gas mixture. The results show that surface modified membranes have superior performance compared to commercial and in-house made hydrophobic membranes such as polypropylene and polytetrafluoroethylene, e.g., in the case of pure CO2 in the shell side and distilled water in the lumen side, the surface modified PEI membrane shows 72% higher absorption flux than commercial membrane contactor, Celgard MiniModule® 0.75X5 which is made of polypropylene membranes, when the liquid velocity is 0.4 m s−1.

► Surface Modifying Macromolecule (SMM) was used to enhance the surface hydrophobicity of PEI HFM.
► The effects of SMM on membrane properties were studied and compared with the properties of PEI membrane without SMM.
► The surface modified PEI HFM was used in contactor application for absorption of CO2 with water.
► The contactor test results show superior performance of surface modified PEI HFM compared to hydrophobic membranes.