Fabrication of antifouling and antibacterial polyethersulfone (PES)/cellulose nanocrystals (CNC) nanocomposite membranes

In this study, cellulose nanocrystals (CNC) were incorporated into polyethersulfone (PES) ultrafiltration membranes to improve their selectivity for separation of protein from water, as well as antifouling properties. PES/CNC nanocomposite membranes were prepared with non-solvent induced phase inversion technique. The effect of CNC loading in the PES on membrane morphology and performance was investigated. The contact angle and water content measurements revealed that the hydrophilicity of PES/CNC membranes enhanced by increasing the CNC content in the casting solution. The pure water flux was increased by introducing 1.0 wt% CNC in the casting solution, while the further addition of CNC has decreased the water flux. The synthesized membranes were used for the removal of protein, bovine serum albumin (BSA), from the water. The BSA rejection ratio increased from 93% to 97% by adding 5.0 wt% CNC into the PES. The flux recovery ratio (FRR) experiments showed significant improvement in the antifouling property of PES/CNC nanocomposite membranes. This study provides valuable insight into the preparation of high-performance nanocomposite membranes for water treatment by blending advanced nanomaterials with polymers. After conditioning by polyhydroxyamines (PAH), the PES/CNC membranes obtained high antibacterial property to gram-positive bacteria Staphylococcus aureus, indicated by the apparent halo zone around the membranes.