Abstract
In this work, a number of cellulose acetate/polyethylene glycol-600 membranes, with different ratios were prepared by 2-stage phase inversion protocol. The permeation properties were studied by subjecting membranes in indigenously fabricated reverse osmosis plant. The flux and salt rejection of membranes were determined. The membrane with highest salt rejection was selected for modification with chitosan. The modified membranes were characterized for their compositional analysis, surface roughness, surface morphology, permeation properties, membrane hydraulic resistance and antibacterial activity. The presence of functional group was determined by FTIR spectra. Chitosan was found to significantly enhance the salt rejection and membrane hydraulic resistance. All modified membranes exhibited remarkable antibacterial properties. The varying nature of nodules and interstices spaces was observed in the images obtained by the atomic forced microscopy. The asymmetric surface morphology of membranes was elucidated from the scanning electron microscope. The synthesis of cellulose acetate membrane, doped with polyethylene glycol and modified with chitosan, provides a convenient access towards the development of sustainable chemistry.
•2-stage phase inversion protocol is devised for synthesis of asymmetric membranes.•A biopolymer (chitosan) is used as an additive.•Salt rejection, membrane hydraulic resistance and bacterial tolerance are improved.•Nodules and interstices spaces are observed in AFM images.•Environmentally benign membranes are fabricated successfully.