EFFECT OF CARBON NANOMATERIALS CONCENTRATION IN NANOCOMPOSITE MEMBRANE FOR METHYL BLUE DYE REMOVAL

Abstract

It is reported that the membrane properties can be enhanced by nanomaterials. However, agglomeration will occur due to the overdose of nanomaterials subsequently deteriorating membrane performance. The project aims to investigate the effect of concentration of cabon nanomaterials: multiwalled carbon nanotubes (MWCNTs) and graphene oxide (GO), on nanocomposite membrane for methyl blue (MB) dye removal. The GO/MWCNTs nanocomposite membranes were synthesized using direct blending method with three concentrations (0.2, 0.5, and 1 wt.%). The synthesized membrane was characterized by surface hydrophilicity, pore size and porosity, surface charge, functional group, and surface morphology. Besides, the performance of the synthesized membrane was evaluated by water permeability test, dye rejection test, and antifouling test. The result shows that the surface hydrophilicity was enhanced when the concentration of nanomaterials increased up to 0.2 wt%. However, higher concentration of nanomaterials reduces the membrane hydrophilicity due to the agglomeration of nanomaterials. The membrane with nanomaterials concentration of 0.2 wt.% (M0.2) has the best performance as it showed 6.85% and 32% improvement in water permeability and dye rejection when compared to the pristine membrane. Besides, M0.2 membrane has relatively good antifouling properties indicated by normalized flux (0.8043). This is due to the enhancement of hydrophilicity and zeta potential of M0.2 membrane by carbon nanomaterials. In short, optimum concentration of carbon nanomaterials are essential to enhance the membrane performance as agglomeration of nanomaterials occurs at high concentration.