Zeolite membrane reactors reactions

Table 10.2 Performance of several zeolite membrane reactors in the xylene isomerization reaction. 

Lin, J.Y.S., Zeolite Membrane Reactor for Water-Gas-Shift Reaction for Hydrogen Production, Proceedings of2007 U.S. DOE Hydrogen Annual Merit Review Meeting, Arlington, VA, May 2007. 

One of the main challenges for zeolite membrane reactors is that optimal reactor operation requires that the membrane flux be in balance with the reaction rate.. Whether acting in an inert or catalytic capacity, the extractive ability of the membrane needs to keep up with the production of the species being removed in order to fully participate in improving the reaction yield [44]. 

Improved selectivity in the liquid-phase oligomerization of i-butene by extraction of a primary product (i-octene C8) in a zeolite membrane reactor (acid resin catalyst bed located on the membrane tube side) with respect to a conventional fixed-bed reactor has been reported [35]. The MFI (silicalite) membrane selectively removes the C8 product from the reaction environment, thus reducing the formation of other unwanted byproducts. Another interesting example is the isobutane (iC4) dehydrogenation carried out in an extractor-type zeolite CMR (including a Pt-based fixed-bed catalyst) in which the removal of the hydrogen allows the equilibrium limitations to be overcome [36],... 

Zeolite membranes may play either a passive or an active role in catalytic (organic) conversion reactions and the potential applications of zeolite membrane reactors are quite promising. Both liquid phase and gas phase reactions may advantageously be carried out in a membrane reactor, and transport from the reaction zone is promoted by continuous removal of the permeating molecules. 

MTBE synthesis from /-butanol and methanol in a membrane reactor has been reported by Salomon et al. [2.453]. Hydrophilic zeolite membranes (mordenite or NaA) were employed to selectively remove water from the reaction atmosphere during the gas-phase synthesis of MTBE. This reaction was carried out over a bed of Amberlyst 15 catalyst packed in the inside of a zeolite tubular membrane. Prior to reaction, the zeolite membranes were characterized by measuring their performance in the separation of the equilibrium mixture containing water, methanol, /-butanol, MTBE, and isobutene. The results obtained with zeolite membrane reactors were compared with those of a fixed-bed reactor (FBR) under the same operating conditions. MTBE yields obtained with the PBMR at 334 K reached 67.6 %, under conditions, where the equilibrium value without product removal (FBR) would be 60.9%. 

Lin s group [49] synthesized bilayer MFI zeolite membrane reactor for WGS reaction. They investigated the membrane reactor for long-term... 

Z. Tang, S. J. Kim, G. K. Reddy, J. Dong, P. Smimiotis, Modified zeolite membrane reactor for high temperature water gas shift reaction, J. Membr. Sci. 354 (2010) 114-122. 

Kim S-J, Xu Z, Reddy GK, Smirniotis P, Dong J. Effect of pressure on high-temperature water gas shift reaction in microporous zeolite membrane reactor. Ind Eng Chem Res 2012 51 1364-1375. 

Zhang Y, Wu Z, Hong Z, Gu X, Xu N. Hydrogen-selective zeolite membrane reactor for low temperature water gas shift reaction. Chem Eng J 2012 197 314—321. 

Zerva, C., Philippopoulos, C. J. (2006). Ceria catalysts for water gas shift reaction influence of preparation method on their activity. Applied Catalysis B Environmental, 67, 105—112. Zhang, Y., Wu, Z., Hong, Z., Gu, X., Xu, N. (2012). Hydrogen-selective zeolite membrane reactor for low temperature water gas shift reaction. Chemical Engineering Journal, 197, 314-321. 

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