Preparation of antibiofouling polyethersulfone mixed matrix NF membrane using photocatalytic activity of ZnO/MWCNTs nanocomposite

Multiwalled carbon nanotubes (MWCNTs) coated by zinc oxide (ZnO) nanoparticle were synthesized, characterized and next, blended in polyethersulfone (PES) membrane casting solution to evaluate influences of the prepared nanocomposite membrane on the performance and antibiofouling properties. The synthesized ZnO/MWCNTs nanocomposites were characterized by scanning electron microscope (SEM) and X-ray diffraction (XRD) analysis. The effect of the embedded nanocomposites on morphology and performance of the prepared membranes was studied by contact angle measurement, pure water flux, milk powder and activated sludge solution filtration, SEM images and surface roughness parameters using atomic force microscopy (AFM) techniques. The pure water flux of the nanocomposite membranes improved considerably after adding of ZnO coated MWCNTs owing to the higher hydrophilicity. The results of fouling resistance showed that 0.5 wt% ZnO/MWCNTs membrane had the best antifouling capacity. Investigation of nanofiltration performance was carried out by investigating the rejection of Direct Red 16. The rejection results revealed that the ZnO/MWCNTs membranes have greater dye removal ability rather than the bare PES. In summary, the results showed that ZnO/MWCNTs membranes presented the best antibiofouling characteristics because of high hydrophilicity and low surface roughness induced by the embedded nanoparticle.