Novel antibifouling nanofiltration polyethersulfone membrane fabricated from embedding TiO2 coated multiwalled carbon nanotubes

Multiwalled carbon nanotubes (MWCNTs) coated by anatase titanium dioxide (TiO2) nanoparticles were synthesized via the precipitation of TiCl4 precursor on the acid oxidized MWCNTs and used in preparation of nanocomposite polyethersulfone (PES) membranes. In this work, the effect of embedding TiO2 coated MWCNTs in PES matrix on membrane morphology, properties and antibiofouling was presented and the obtained results were compared with the prepared oxidized MWCNTs and TiO2 blended PES membranes. X-ray diffraction (XRD) and transmission electron microscopy (TEM) analyses showed that the formed TiO2 on the surface of MWCNTs had anatase nanostructure with size in the range of 10-20 nm. The scanning electron microscopy (SEM) images displayed a finger-like and porous structure for all NF membranes and showed that agglomeration of TiO2 coated MWCNTs is very low. Contact angle measurements indicated that coating of TiO2 nanoparticles on the surface of oxidized MWCNTs improved the hydrophilicity of the obtained membranes. The pure water flux of the blend membranes increased with the content of TiO2 coated MWCNTs. Fouling resistances of membranes evaluated by whey solution filtration revealed that 0.1 wt.% TiO2 coated MWCNTs membrane had the best antibiofouling properties due to its lowest surface roughness and synergistic photocatalytic activity induced by incorporated nanoparticles. (C) 2012 Elsevier B.V. All rights reserved.