Retention of bisphenol A and caffeine on PES/PES-CNTs membranes-performance and effect of different conditions

This study describes retention and fouling behavior of polyethersulfone/polyethersulfone-carbon nanotube (PES/PES-CNT) membranes in different filtration conditions. PES/PES-CNT membranes were prepared by inverse-phase method. Single-walled CNTs and single-walled CNTs functionalized with carboxyl group were employed for a modification. PES was selected as basic membrane material. Retention tests were carried out for two organic chemicals, that is, bisphenol A and caffeine. It was found that retention of micropollutants was mainly dependent on their physicochemical properties and membrane type. Removal of highly hydrophobic substance: bisphenol A was higher than for caffeine, which has hydrophilic character. Adsorption on membrane played a key role in their removal. Adsorption was more intensive on modified membrane as an effect of occurrence of nanotubes in its structure and surface. In other words, CNTs enhanced sorption potential of nanocomposite membranes. Moreover, modified membranes had better antifouling properties.