Surface Modification of PES Nanofiltration Membrane by Chitosan-GO Nano-plates Coating for Reduction of Fouling and Performance Enhancement

In the current study, prepared PES nanofiltration membranes with phase inversion method were modified by the novel composite chitosan/GO (graphene oxide) nano-sheets coating process and the effect of coating on performance and membrane antifouling properties was investigated. The results revealed that the salt rejection strongly improved, and their hydrophilicity enhanced rather than PES. The rejection increased from 68% for PES to 94% due to pore size reduction and improvement in adsorption. But permeability flux was decreased by increasing skin layer after coating. In addition, contact angle was decreased because of chitosan and GO nano-sheets hydrophilic nature. The surface morphology was changed from rough surface to smoother one by coating. Finally, flux recovery ratio and total fouling ratio were in good agreement with contact angle results and roughness parameters. Moreover, an increase in flux recovery ratio and reduction of total fouling ratio indicated successfully enhancement of antifouling properties of membrane by coating of chitosan/GO nan-osheets.