Dehydration of Isopropanol by Novel Poly(vinyl alcohol)−Silicone Hybrid Membranes

Novel organic−inorganic hybrid membranes were prepared through sol−gel reaction of poly(vinyl alcohol) (PVA) with γ-aminopropyl-triethoxysilane (APTEOS). The membranes were characterized by FT−IR, solid-state NMR, WXRD, SEM, and contact angle meter. The swelling degree of the hybrid membranes in an aqueous isopropanol (IPA) solution has been controlled owing to the formation of hydrogen and covalent bonds in the membrane matrix. The effect of APTEOS content in the membrane, feed flow, feed concentration, and temperature on pervaporation (PV) performance was investigated. The water permselectivity increased, and permeation flux increased quickly with increasing APTEOS content when it was less than 5 wt %. The membrane containing 5 wt % of APTEOS has the highest separation factor of 1580 with a permeation flux of 26.5 × 10 -3 kg·m -2 ·h -1 at 30 °C in PV separation of 90 wt % IPA in water. The temperature dependence of permeation flux can be described by an Arrhenius-type relationship.