Intercalation of GO-Ag nanoparticles in cellulose acetate nanofiltration mixed matrix membrane for efficient removal of chromium and cobalt ions from wastewater

Cellulose acetate (CA)/Polyethylene glycol (PEG) blended composite nanofiltration (NF) membrane encompassing graphene oxide-silver (GO-Ag) nanoparticles (NPs) has been successfully synthesized by dissolution casting techniques. The effect of different NP loadings on membrane morphology, surface roughness, hydrophilicity surface charge and permeation flux were evaluated. Owing to Donnon exclusion, steric hindrance, and solution diffusion mechanism, the synthesized modified membranes exhibited excellent rejection rates in the order of Co (II) (99 %) > Cr (VI) (91 %). Furthermore, pure water flux (PWF) of the modified membrane was obtained 660.56 L/m²h which is 78.45 % greater than pristine membrane. Due to its high surface hydrophilicity, surface roughness, and porosity, modified membrane exhibited good antifouling characteristics. The results indicated that the intercalation of GO-Ag NPs with a loading ratio of 0.8 wt% leads to the optimum membrane for Cr (VI) and Co (II) removal. The present work demonstrates the potential application of GO-Ag/CA modified NF mixed matrix membrane for serving as a promising platform for eliminating heavy metal ions in wastewater.