Release Time:2019-03-09  Hits:

Indexed by: Journal Article

Date of Publication: 2012-02-15

Journal: JOURNAL OF MEMBRANE SCIENCE

Included Journals: Scopus、EI、SCIE

Volume: 390

Page Number: 175-181

ISSN: 0376-7388

Key Words: Silylated MCM-48 membrane; Adsorption amount; Pervaporation; Separation factor

Abstract: The MCM-48 type materials and membranes had been successfully silylated with different alkyl chains (methyl, propyl and n-octyl). The silylated MCM-48 membranes prepared on supports with pore size of 1 mu m had a good effect on separation of the ethyl acetate (EA)/water mixture. The materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), IR spectroscopy, pervaporation. These results showed that the silylated MCM-48 type materials could adsorb large amount of EA, about 145 mg/g for C8H17-MCM-48 at 7 kPa at the room temperature, which was ten times of the Si-MCM-48'. Besides this, the C8H17-MCM-48 membranes had EA/H2O separation factor of 251 at room temperature and 123 at 50 degrees C with the total flux 4.3 and 6.6 kg/(m(2) h), respectively. The long-chain alkyl groups grafted in the membrane pore could enhance temperature tolerance of the membrane for separating EA/H2O. Under the same conditions, the CH3- and C3H7-MCM-48 membranes had lower separation factor and larger total flux. The phenomenon in the separation experiments was controlled by the solution-diffusion mechanism. EA molecules were firstly adsorbed in the silylated pores selectively and made up a compact hydrophobic membrane, which could prevent the penetration of the water, resulting in the high EA selectivity. (C) 2011 Elsevier B. V. All rights reserved.