TiO2 nanoparticle embedded PEEKWC/PEI cross-linked ultrafiltration membrane: Improvement in flux and anti-fouling properties

Abstract

Based on the previous study, the properties, separation efficiencies, and anti-fouling performances of TiO2 nanoparticle embedded PEEKWC/PEI cross-linked ultrafiltration membrane made via non-solvent-induced phase separation were investigated. SEM, contact angle measurement, ATR-FTIR, and other methods were used to characterize the membranes, and then the pure water flux (PWF) and dye rejection were measured. The TiO2 nanoparticle embedded PEEKWC/PEI cross-linked ultrafiltration membranes were prepared by stepwise solution blending method. Compared to the pristine PEEKWC/PEI cross-linked ultrafiltration membrane, the anti-fouling and pure water flux performances were enhanced as the addition of TiO2 nanoparticles. The pure water flux of TiO2 nanoparticle embedded membranes was significantly increased and could even reach 3368.2 LMH at 5 bar much greater than that of the pristine PEEKWC/PEI ultrafiltration membrane (1423.8 LMH), remaining a retention rate for BBR higher than 98.5%. And the TiO2 nanoparticle embedded PEEKWC/PEI cross-linked ultrafiltration membranes exhibited a certain degree of increase of FRR (higher than 80%) after UV illumination. After a series of characterisation, the dye wastewater treatment property of membranes was assessed through filtration of Coomassie brilliant blue and Congo red solutions and researches were conducted on the anti-fouling capabilities of membranes. The TiO2 nanoparticle embedded PEEKWC/PEI cross-linked ultrafiltration membranes exhibited self-cleaning efficiency with lower irreversible fouling ratio. The pure water flux recovery ratio following dye fouling was higher after being exposed to UV irradiation, which could be attributed to the TiO2 nanoparticles' photocatalytic destruction of organic pollutants.