Combined fouling of forward osmosis membrane by alginate and TiO2 nanoparticles and fouling mitigation mechanisms

Forward osmosis (FO) is a promising technology for water treatment, but its fouling mechanisms are poorly understood compared to other membrane-based processes. This study focuses on combined caused by alginate (SA) and TiO2 nanoparticles, which serve as representative organic inorganic foulants, respectively. The results show that the co-presence of can effectively mitigate membrane SA under vas feed chemistries (Ca2+ concentrations). negative charge foulants increased in presence TiO2, alleviating aggregation due electrostatic steric stabilization. behavior were characterized attenuated total reflection-Fourier transformation infrared spectroscopy (ATR-FTIR) coupled with isothermal titration calorimetry (ITC) atomic force microscopy (AFM) at molecular level. Combined SA-TiO2 had lower binding affinity Ca2+ than single SA, was spontaneously exothermic dominated interaction reduce fouling. provides new insight into nanoparticles-mediated FO process. It also demonstrates an integrated ATR-FTIR/ITC/AFM approach provide useful information understanding complicated interactions between foulants.