Polyvinyl alcohol and graphene oxide blending surface coated alumina hollow fiber (AHF) membrane for pervaporation dehydration of epichlorohydrin(ECH)/ isopropanol(IPA)/water ternary feed mixture

Abstract

For pervaporation dehydration of ternary azeotropes ECH/IPA/water (50/30/20, w/w,%) produced in epoxy resin manufacturing process, Graphite nanopowder was oxidized to prepare graphene oxide (GO) nanosheets, which were incorporated into a polyvinyl alcohol (PVA)-tetraethyl orthosilicate (TEOS) solution. The GO-PVA-TEOS solution was coated on the surface of a nanoporous alumina hollow fiber (AHF) membrane. The pore size and element composition on the AHF were determined using FE-SEM and energy dispersive spectroscopy. The coating thickness of the GO-PVA-TEOS membrane layer on the AHF was measured using FE-SEM analysis, and XPS, FTIR analysis of the membrane was conducted to confirm the condensation reaction between PVA and TEOS. Pervaporation dehydration of the epichlorohydrin/ isopropanol/water mixtures was conducted using the AHF membranes with and without GO in PVA-TEOS. For pervaporation output, with the addition of 0–1.5 wt% GO in the PVA-TEOS, it was quantitatively reported that the flux declined from 0.17 to 0.09 kg/m2h and the separation factor increased sharply from 1450 to 4844 with feed consisting of the ECH/IPA/water (50/30/20, w/w,%) solution at 30 °C. In terms of the long-term (240 h) pervaporation stability evaluation of 1.0 wt% GO-incorporated membrane, the excellent separation efficiency with increased of flux was obtained.