Oily wastewater treatment by blend polyether imide‐sulfonated poly (ether ether keton) hollow fibre membrane through a side‐stream MBR process

Abstract The blend polyether imide‐sulfonated poly (ether ether keton) (PEI‐sPEEK) hollow fibre membrane was prepared for oily wastewater treatment of the natural gas liquid plant (NGL‐900, Gachsaran, Iran) through a side‐stream membrane bioreactor (MBR) process. Using PEI/sPEEK ratio of 90/10, a good compatibility of PEI and sPEEK polymers was achieved by DSC analysis. The modified membrane showed an open structure with large finger‐likes, overall porosity of about 80% and mean surface pore size of 10 nm. In addition, the membrane hydrophilicity significantly improved as water contact angle reduced from about 82° to 58°. In the MBR process, the improved membrane presented oil rejection, COD, TSS and turbidity reduction of about 99.9%, 99.7%, 98.9%, and 99.7%, respectively. The membrane showed a good antifouling property with flux recovery ratio (FRR) of 80.2% where the cake filtration was the dominant fouling mechanism. The modified membrane can be a promising alternative for treatment of industrial oily wastewater due to the enhanced properties.