Enabling improved PSF nanocomposite membrane for wastewater treatment with selective nanotubular morphology of PANI/ZnO†

Abstract

Increased population and rapid industrialization are depleting and polluting the fresh water resources at an alarming rate, leading to freshwater scarcity. Water pollution caused by heavy metal ions and dyes has become a major problem and has numerous adverse effects on human health. In recent years, nanotechnology has gained much attention in the field of water purification but new approaches in nanomaterials are still required to boost their removal efficiency. This study deals with membrane fabrication by using a novel hybrid polysulfone (PSF)/polyaniline (PANI) nanotube with zinc oxide (ZnO) nanorods via the phase inversion method. Two different schemes were employed for membrane fabrication, i.e. PSF/PANI blend and ZnO–(PSF/PANI). Nanomaterials were characterized by FTIR, UV, SEM and XRD. Membrane properties such as porosity, pure water flux (PWF), contact angles, solvent contents, protein rejection and flux recovery ratio (FRR) were studied. Incorporation of PANI and ZnO as nanofillers significantly improved solvent content, lowered water contact angles and enhanced antifouling properties. The FRR reached about 87.4% and PWF also increased from 20 to 136.3 L m⁻² h⁻¹ bar⁻¹ representing enhanced hydrophilicity. Among various compositions, the PP 0.25 nanocomposite membrane demonstrated a maximum removal of 91.2% MB and 94.3% Mn⁷⁺ and PPZ 0.25 showed removal of 95.18% MB and 96.21% Mn⁷⁺ at 0.1 MPa. Based on the above results, the PSF/PANI and ZnO–(PSF/PANI) nanocomposite membranes are recommended for practical use in wastewater treatment.