Terpolymer Composites Membranes for Polymer Enhanced Ultrafiltration and Photochemical Degradation of Dissolved Organic Pollutants From Water

ABSTRACT Polymer composites were prepared by in situ incorporation of sodium montmorillonite (NaMMT) and TiO 2 into a growing terpolymer during polymerization of acrylonitrile (AN), N ‐vinyl‐2‐pyrrolidone (VP), and acrylic acid (AA). Several composites were formulated by altering the AN: VP: AA molar ratios and weight percentages of NaMMT and TiO 2 fillers. Ultrafiltration (UF) membranes were prepared from these composites by phase inversion of their dimethyl acetamide (DMAc) solutions in water. The composite membranes were characterized and used for removal of a cationic dye, methylene blue (MB), from water in the presence of a polyelectrolyte sodium polyacrylate (NaPA) using polymer enhanced UF (PEUF). The effect of copolymer compositions, wt.% of clay and TiO 2 , and the concentration of the NaPA on flux and dye rejection were studied. The unfilled M 20 copolymer membrane containing 20 M% of VP+AA and the same filled membrane containing 1 wt.% clay and 1 wt.% TiO 2 exhibited a flux (L·m −2 ·h −1 )/rejection (%) of 135.67/93.7 and 146.7/95, respectively, from a feed of 0.15 mmol·L −1 MB in the presence of 0.3 mmol·L −1 NaPA, at a transmembrane pressure of 0.2 MPa. The filled membrane showed 94% degradation of 0.15 mmol·L −1 MB for 100 min exposure to sunlight with a first order rate constant of 0.0054 min −1 .