Nanocomposite Membranes of Poly(Vinyl Alcohol) Loaded with Polyaniline-Coated TiO2 and TiO2 Nanoparticles for the Pervaporation Dehydration of Aqueous Mixtures of 1,4-Dioxane and Tetrahydrofuran

Nanocomposite membranes of poly(vinyl alcohol)–polyaniline (PANI)-coated titanium dioxide (PVA–PANI–TiO2), as well as TiO2, cross-linked with glutaraldehyde were tested for their suitability in dehydrating aqueous mixtures of 1,4-dioxane or tetrahydrofuran (THF) by pervaporation (PV). The effect of feed composition and filler loading on PV separation performance was examined. Sorption studies were performed in feed mixtures to assess the extent of interaction between membranes and feed components. The addition of a small amount of nano-sized filler particles into a cross-linked PVA membrane was responsible for an increase in membrane selectivity to water. Among the cross-linked nanocomposite PVA membranes, TiO2 coated with 0.5 wt% PANI gave higher sorption than other membranes. Sorption of the cross-linked (unfilled) PVA membranes was higher compared to all the nanocomposite membranes. Addition of filler particles reduced the extent of sorption with improved membrane performance.