Enhancing the RO performance of cellulose acetate membrane using chitosan nanoparticles

Asymmetric reverse osmosis membranes of cellulose acetate (CA) in presence of chitosan nanoparticles as anti-biofouling material were prepared using the phase-inversion technique. The effect of some preparation parameters on the membrane properties, e.g. polymer composition, evaporation time and annealing temperature were studied. FTIR, TGA, SEM and Contact angle were carried out to characterize the produced membranes. The water flux and salt rejection of the membranes were assessed using 35 g/L Nacl in a dead end filtration system. The results revealed that the addition of chitosan nanoparticles increased the water flux from 6 L/m2.h for blank (CA-0) to about 18 L/m2.h for (CA-2) membrane containing 2% chitosan nanoparticles with increment of salt rejection from 89 to 94%. For membrane with proper salt rejection it should be annealed at 80 °C prior to filtration test. The static adhesion test indicated enhancement in fouling resistance of the membrane containing chitosan nanoparticles to bacterial attack.