(486f) Second Interfacial Polymerization of Thin-Film Composite Polyamide Membrane with Polyethyleneimine for Forward Osmosis Applications

In this work, a fast and simple surface modification-second interfacial polymerization (SIP) of thin-film composite (TFC) membranes using polyethyleneimine (PEI) of various molecular weights, was applied to improve the separation performance for forward osmosis (FO) applications. Compared to the control TFC membranes, PEI -modified membranes exhibit higher water flux and lower fouling propensity. The effects of PEI molecular weight and PEI concentration on the membrane morphology and separation performance were investigated systematically with various characterizations. Post-treatment to surface modified membranes was carried out using four aqueous solutions of different pH values. Meanwhile, the FO performance, intrinsic separation properties and antifouling properties of these post-treated membranes were also studied. In comparison with the surface-modified TFC membranes with PEI, the post-treated TFC membranes show higher water flux and improved anti-fouling properties, especially those post-treated with acidic or alkaline aqueous solutions.