Effect of Ethylene Glycol as Pore Former on Polyphenylsulfone Hollow Fiber Membrane for Crude Palm Oil Deacidification through Membrane Contactor

In this study, polyphenylsulfone (PPSU) hollow fiber membrane was fabricated via a wet spinning method with the addition of ethylene glycol (EG) in the range of 0-10 wt% as the additive. The EG was added to improve the membrane pore formation and interconnectivity for better membrane contactor performance in extracting and removing the free fatty acid (FFA) from crude palm oil (CPO). Four different hollow fiber membranes consisted of 14PPSU-0EG, 14PPSU-2EG, 14PPSU-6EG and 14PPSU-10EG were characterized for their morphologies, wettability and pore sizes. From the characterization, it was proven that the presence of EG has promoted the formation of more uniform interconnected finger-like structure with double-layer membrane morphology. In membrane contactor performance testing, sodium hydroxide (NaOH) was used as liquid extractant due to the high affinity of free fatty acid (FFA) towards NaOH. Unfortunately, the new developed PPSU hollow fiber membrane with the presence of EG has significantly (P<0.05) reduced the membrane contactor performance from 16.54% FFA removal using 14PPSU-0EG to less than 5% FFA removal in the treated CPO permeate after 3 hours operation. It may be due to a significant (P<0.05) reduction in membrane hydrophobicity which reduced the oil wettability and interfacial contact between CPO and NaOH at the membrane interface. Nevertheless, no soap formation was detected in the permeate collection.