(695c) Novel Organic-Inorganic Thin Film Composite Membranes for Forward Osmosis Applications with Improved Water Flux and Anti-Fouling Performance

In this work, novel thin film composite (TFC) forward osmosis (FO) membranes are developed via interfacial polymerization on the polyacrylnitrile (PAN) substrate with blended diamines of m-phenylenediamine (MPD) and N-[3-(trimethoxysilyl) propyl]ethylenediamine (NPED) used.  Effects of the PAN substrate hydrolyzed by sodium hydroxide for different time periods are studied on the membrane properties and performance of the resultant TFC membranes. By varying the monomer ratio of NPED and MPD in the aqueous phase, the membrane morphology and FO performance of the TFC membranes are also investigated. Both the PAN substrates and the TFC membranes are characterized by various techniques, including FTIR, SEM and water contact angle, etc. to examine changes in the chemical structures and the surface properties. The FO performance shows an improvement of the water flux and a sacrifice of the reverse salt flux when NPED/MPD mass ratio increases because of the enhanced hydrophilicity and larger free volume in the PA layer. In addition, the promising anti-fouling property of the TFC membranes with various MPD/NPED monomer ratios is also studied.