Enhanced water flux through ultrafiltration polysulfone membrane via addition‐removal of silica nano‐particles: Synthesis and characterization

In the present paper, hierarchically structured ultrafiltration polysulfone (PSf) membrane was prepared to explore the effect of addition and subsequent removal of SiO2 nano‐particles on the membrane morphology, hydrophilicity, and separation properties. The PSf based membranes namely PSf, PSf/SiO2 and PSf/WSiO2 (i.e. SiO2 nano‐particles was acid‐washed and removed from PSf/SiO2), were synthesized and characterized by different characterization methods. Pure water flux through the membranes was determined using a filtration unit operating at a continuous dead‐end flow mode. The modification enhanced the morphology, hydrophobicity, porosity and transport properties of the modified membranes, although the molecular weight cut‐off (MWCO) of the membranes was not changed considerably. In comparison, PSf/WSiO2 membrane exhibited excellent pure water flux (about 4.5 times the flux of PSf, and 17 times the flux of PSf/SiO2), although antifouling property of PSf/SiO2 in separation of bovine serum albumin (BSA) was better than that of PSf and PSf/WSiO2 membranes. The results suggested that the addition/removal of sacrificial solid fillers within/from a membrane matrix may provide a promising strategy to enhance PSf membrane transport property.