Performance Enhancement of Bio-fouling Resistant Cellulose triacetate-based Osmosis Membranes using Functionalized Multiwalled Carbon Nanotube & Graphene Oxide

In this study, cellulose triacetate (CTA) based nanocomposite membranes were developed by incorporation of carboxylic acid functionalized multiwalled carbon-nanotube (cMWCNT) and graphene oxide (GO) which have enhancement of both flux and fouling resistance properties of the membranes. Membranes were casted at room temperature and annealed at 90 degrees C hot water for 10 minutes. The incorporation level of both the nanomaterials is 1.5% of the CTA polymer weight in the nanocomposite membranes. Prepared membranes were characterized in terms of water contact angle, surface morphology and mechanical strength. The performance of the membranes was evaluated both in reverse osmosis (RO) and forward osmosis (FO) mode. The water flux is observed to increase by similar to 43% in CTA-cMWCNT and similar to 69% in CTA-GO membranes than the pure CTA membranes in RO mode (2000ppm NaCl feed at 1551kPa applied pressure) but it is similar to 41% and similar to 86% in FO mode (DI water as feed & 1.0 molar NaCl as draw solution) for CTA-cMWCNT and CTA-GO membranes respectively. Nanocomposite membranes containing functionalized CNT & GO were found more biofouling resistant property. The flux recovery is similar to 62% in pure CTA membrane, whereas it is similar to 73% for CTA-cMWCNT and similar to 82% for CTA-GO membranes.