Fe2O3 nanocomposite PVC membrane with enhanced properties and separation performance

Abstract

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 (0–2wt%) 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 (782L/m2h), 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.