JOURNAL OF MEMBRANE SCIENCE, vol.529, pp.170-184, 2017 (SCI-Expanded)
Organic and inorganic mixed matrix membranes are one of the most promising new membrane materials for ultrafiltration (UF). separation applications. In this study, PVC/Fe2O3-mixed UF membranes were fabricated at different nano-Fe2O3 loading levels (0-2 wt%) using the phase inversion method. Surface chemical compositions, surface and cross-section morphologies and characteristics, hydrophilicity and mechanical strength of the membranes were characterized using several analytical techniques and instruments such as scanning electron microscopy (SEM), atomic force microscopy (AFM), a contact angle goniometer, dynamic mechanical analyzer (DMA) and a nanoindenter. Membrane performance was also tested in terms of water flux, solute rejection, and anti-fouling characteristics. The experimental results demonstrated that the overall membrane structure was remarkably enhanced with the addition of Fe2O3 nanoparticles up to a loading of 1%. This was due to the membrane's more hydrophilic and smoother surface and a more elongated finger-like structure as well as higher porosity and pore size. The nanoindentation experiments indicated that Fe2O3 incorporation greatly enhanced the hardness of the membranes providing a higher pore integrity degree. However, higher Fe2O3 content caused a nanoparticle aggregation resulting in a decline in the performance of the composite membranes. Compared with the pristine PVC membrane, the membrane containing 1% Fe2O3 exhibited better capabilities such as the enhanced water flux (782 L/m(2)h), higher sodium alginate (SA) rejection rate (91.9%) and better antifouling properties. The PVC/Fe2O3 nanocomposite membranes may have applicable potential in water and wastewater treatment applications based on their low price, enhanced mechanical strength, high permeability, high removal efficiency, and good antifouling performance.