Control of organic and biological fouling of polyethersulfone membrane by blending and surface modification using natural additives

Abstract

In this study, a modified polyethersulfone (PES) membrane was fabricated by blending collagen (COL) in the PES dope solution and the subsequent coating with chitosan (CHI) – polyphenon from green tea (PGT). The antifouling and antibacterial properties of all prepared membranes were evaluated. The results demonstrated that the CHI and PGT coating on COL-incorporated membrane exhibited enhanced hydrophilicity and flux recovery compared with the pristine PES membrane. The best solute rejection and control of foulant adsorption were observed with the optimized modified membrane (0.3COL@0.6CHI/0.6PGT). Also, the 0.3COL@0.6CHI/0.6PGT membrane showed a predominant inhibition zone area, suggesting the excellent antibacterial properties of the membrane. During surface water filtration, the removal rates of COD, TDS, conductivity, and turbidity were enhanced from 32.2 % to 52.5 %, from 67.2 % to 72.7 %, from 12.9 % to 24.7 %, and from 70.8 % to 92.2 %, respectively, by using the optimized modified membrane. Furthermore, the outstanding performance of membrane stability, in terms of hydrophilicity and antibacterial properties, was also confirmed by water contact angle and inhibition zone analyses. This study provided an effective and environmentally-friendly method for modification of PES membrane with enhanced antifouling and antibacterial performance.