Fabrication of poly(ether sulfone)/poly(zinc acrylate) ultrafiltration membrane with anti-biofouling properties

Biofouling is a severe problem for membrane process. Incorporating biocides such as heavy metals into polymer membranes have been demonstrated for their effectiveness in anti-bacterial performance; however, the metal ion leaches due to the poor compatibility of the metal ions and the polymer. The bactericidal effect will be disappeared and the unexpected pores will be formed when all the metal ions leach out. To overcome this problem, an anti-biofouling poly(ether sulfone)/poly(zinc acrylate) (PES/PZA) ultrafiltration composite membrane was investigated by immobilizing Zn ions onto polymer chains. The PES/PZA composite membrane has a good anti-biofouling property during a 3 months test in an aerobic bioreactor treating municipal wastewater. The higher the PZA content, the better anti-biofouling ability the membrane has. The Zn2+ content can be restored by incubating the membrane in a solution containing Zn2+ (even after the Zn2+ has been replaced by other cations during the water treatment), which secures the long time anti-biofouling properties of the membranes.