Preparation and characterization of TiO2/Pebax/(PSf-PES) thin film nanocomposite membrane for humic acid removal from water

New thin film composite (TFC) membrane was prepared via coating of Pebax on PSf-PES blend membrane as support, and its application in wastewater treatment was investigated. To modify this membrane, hydrophilic TiO2 nanoparticles were coated on its surface at different loadings via dip coating technique. The as-prepared membrane was characterized using Fourier transform infrared spectroscopy, scanning electron microscopy (SEM), field emission SEM, and contact angle analysis. The Fourier transform infrared spectroscopy analysis and surface SEM images indicated that TiO2 was successfully coated on the membrane surface. In addition, the results stated that the hydrophilicity and roughness of membrane surface increased by addition of TiO2 nanoparticles. Performance of TFC and modified TFC membranes was evaluated through humic acid removal from aqueous solution. Maximum permeate flux and humic acid rejection were obtained at 0.03 and 0.01wt% TiO2 loadings, respectively. Rejection was enhanced from 96.38% to 98.92% by the increase of feed concentration from 10 to 30ppm. Additionally, membrane antifouling parameters at different pressures and feed concentration were determined. The results indicated that surface modification of membranes could be an effective method for improvement of membrane antifouling property.