Performance of PVDF/Multi-nanoparticles Composite Hollow Fibre Ultrafiltration Membranes

Polyvinylidene fluoride (PVDF)/multi-nanoparticles composite hollow fibreultrafiltration (UF) membranes were prepared with different compositions ofSiO2/TiO2/Al2O3 nanoparticles in PVDF/DMAc/NMP solution by wet-spinningmethod. Behaviour of nanoparticles on membrane dopes were evaluated by theviscosity and surface tension. By adding nanoparticles, obviously the membrane dopeviscosity increased; however, the surface tension of each membrane dope changedinconsistently. The hollow fibre membranes were characterized by SEM, mechanicaltesting, TGA, permeability and rejection test, porosity measurement and pore sizedistribution. The test results indicate that different nanoparticles and their relatedcompositions induce different characteristics on membrane morphology, mechanicalproperty, thermal stability, permeation property, as well as porosity and pore sizedistribution, due to the different particle characteristic, the combination effect and thesize effect. For membranes with PVDFM2 (18 wt% PVDF, 1 wt% TiO2 (P25), 1 wt%SiO2 and 1 wt% Al2O3) dope and PVDFM5 (18 wt% PVDF, 2 wt% TiO2 (P25) and 1 wt%Al2O3), the pure water permeation flux and bovine serum albumin rejection reach179 L.m^-2.h^-1.bar^-1 and 98.9%, 352 L.m^-2.h^-1.bar-1 and 89.1%, respectively; while theirmean efficient pore sizes are 10.1 nm and 11.0 nm, and both membranes presentnarrow pore size distribution and other good performances.