Polymer Engineering and Science, Vol.58, No.3, 405-415, 2018
Development of mesoporous carbon incorporated hybrid membranes for separation of azeotropic mixtures by pervaporation
Using a solution technique, tetraethylorthosilicate crosslinked hybrid poly(vinyl alcohol) membrane was prepared. The membrane was further incorporated with 0, 10, 20, and 30 mass% of mesoporous carbon and the membranes thus obtained were designated as M-1, M-2, M-3, and M-4, respectively. The physico-chemical properties of these membranes were investigated using Fourier transform infrared spectroscopy, wide-angle X-ray diffraction, differential scanning calorimetry, thermogravimetry analysis, and scanning electron microscopy. The effects of mesoporous carbon and feed composition on pervaporation performance of the membranes were systematically investigated. The membrane M-4 exhibited the highest separation factor of 4,082 with a flux of 1.93 x 10(-2) kg/m(2)h at 30 degrees C for 10 mass% of water in the feed. Total flux and flux of water are overlapping each other, manifesting that these membranes could be used to break the azeotropic point of water-isopropanol mixtures effectively. From the temperature dependent diffusion and permeation values, the Arrhenius activation parameters were estimated. The positive heat of sorption values was obtained for M-1, M-2, and M-3, suggesting that Henry's mode of sorption is predominant, giving an endothermic contribution. On the contrary, membrane M-4 exhibited negative H-s value suggesting that the sorption process was dominated by exothermic contribution. POLYM. ENG. SCI., 58:405-415, 2018. (c) 2017 Society of Plastics Engineers