Analysis of Membrane Fouling of nZVI@PVDF Using Infrared Spectroscopy-multivariable Curve Resolution Analysis

Xanthan gum (XG) and humic acid (HA) belonging to dissolved organic matter are the main substances in membrane fouling, and their interaction affects the membrane fouling process. In this study, the fouling process of nZVI@PVDF membranes used to filter different concentrations of XG and HA were investigated by infrared spectroscopy-multivariable curve resolution analysis. The results showed that the interaction between polysaccharides and organic matter in water samples can affect membrane fouling. When the proportion of mixed pollutants in water samples changes, the degree of membrane fouling varied. The simulated water sample containing 25% XG caused the most serious membrane fouling, while the simulated water sample containing 60% XG caused the least membrane fouling. The results of ATR-IR combined with MCR-ALS showed that as the filtration time and the proportion of pollutants in water samples change, the dominant pollutants on the membrane surface will be different. For the simulated water sample with 25% XG and 75%HA, the main pollutant on the membrane surface was XG, while the main pollutant on the membrane surface of the simulated water sample with 60% XG and 40%HA was HA. In addition, the correlation between transparent extracellular polymers (TEP) and membrane fouling had also been verified in this study. The higher the TEP content, the more serious the membrane fouling.