Preparation and characterization of nanoparticle-filled, mixed-matrix membranes for the pervaporation dehydration of isopropyl alcohol

Novel polymeric mixed-matrix membranes (MMMs) were prepared by the incorporation of different amounts of 13X zeolite into a sodium carboxymethylcellulose (NaCMC)/poly(vinyl alcohol) (PVA) blend matrix. The resulting MMMs were characterized by attenuated total reflectanceFourier transform infrared spectroscopy to analyze the possible chemical reactions between NaCMC, PVA, zeolites, and glutaraldehyde. Scanning electron microscopy, differential scanning calorimetry, thermogravimetric analysis, and X-ray diffraction were used to analyze the surface morphology, thermal stability, and crystallinity, respectively, of the membranes. Swellings studies were performed at 35 degrees C, and we found that membranes containing 20 wt % zeolite showed higher values (960 kg m-2 h-1) at 17.5 wt % water in an isopropyl alcohol (IPA)/water mixture. Pervaporation (PV) experiments were also performed to evaluate the membrane performance in different compositions of the IPA/water mixture at 35 degrees C. The mechanical properties were also tested, and we found that the optimum mechanical strength and percentage elongation at break were 42.24 N/mm2 and 3.38, respectively, for the membrane containing 15 wt % zeolite. The experimental results show that both the flux and selectivity increased with increasing zeolite content. The membrane containing 20 wt % zeolite showed the highest separation selectivity (5118) with a substantial flux of 0.121 kg m-2 h-1 at 35 degrees C and with 10 wt % water in the feed; this suggested that the membranes could be used effectively to break the azeotropic point of the waterIPA mixture, so as to remove a small amount of water from IPA. (C) 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012