Study on a novel polyamide-urea reverse osmosis composite membrane (ICIC-MPD): II. Analysis of membrane antifouling performance

In this study, a novel polyamide-urea reverse osmosis composite membrane (ICIC-MPD) was tested for its antifouling performance, and compared with the TMC-MPD and ESPA membranes. The three membranes were characterized for their surface properties such as hydrophilicity and surface roughness. The fouling experiments in laboratory scale were performed with lake water and four simulated aqueous solutions. Membrane fouling data were correlated with the measured surface properties. Further, a combination of scanning electron microscope (SEM) and attenuated total reflectance infrared (ATR-IR) or energy dispersive analysis of X-ray (EDX) was utilized to confirm the existence and to examine the morphology of foulants. Results showed that all three membranes were fouled in the five test solutions during the fouling test; however the ICIC-MPD membrane had a lower fouling rate than TMC-MPD and ESPA membranes. It was also found that the antifouling properties of these membranes were closely correlated with their hydrophilicity and surface roughness: higher hydrophilicity and lower surface roughness lead to higher fouling resistance. In addition, from the contact angle values and the AFM photographs, it was confirmed that the favorable hydrophilicity and smoother surface of ICIC-MPD membrane contributed to its better resistance to fouling. As a result, the ICIC-MPD membrane may have favorable antifouling performance.