Palladium membrane reactors reactor

The auto-thermal reaction of ethanol occurred in the shell side of a palladium membrane reactor in which a Zn-Cu/AlaOs industrial catalyst (MDC-3) was packed with silica powder. Ethanol-water mixture (nH2o/nEioH=l or 3) and oxygen (noa/nEioH=0.2,0.776 or 1.035) are fed concurrently to the shell side. The reaction temperatures were set at 593-723 K and the pijrasures were 3 10 atm. 

Figure 4. Comparison of Propane Aromatization Performances of a Palladium Membrane Reactor (PMR) and a Conventional Reactor (CR) using a Ga-H-ZSM-5 Catalyst...

Lin, Y.M. and M.H. Rei, Study on the hydrogen production from methanol steam reforming in supported palladium membrane reactor, Catal. Today, 67, 77-84, 2001b. 

Franz et al. [93] developed a palladium membrane micro reactor for hydrogen separation based on MEMS technology, which incorporated integrated devices for heating and temperature measurement. The reactor consisted of two channels separated by the membrane, which was composed of three layers. Two of them, which were made of silicon nitride introduced by low-pressure chemical vapor deposition (0.3 pm thick) and silicon oxide by temperature treatment (0.2 pm thick), served as perforated supports for the palladium membrane. Both layers were deposited on a silicon wafer and subsequently removed from one side completely... 

Figure 2.63 Micro fabrication sequence for the silicon component of the palladium membrane reactor [93] (by courtesy of Springer-Verlag).

Uemiya, S., Sato, N., Inoue, H., Ando, H. and Kikuchi, E. (1991) The water-gas shift reaction assisted by palladium membrane reactor. Industrial e[ Engineering Chemistry Research, 30, 585. 

Lin Y.-M., Rei M.-H. Process development for generating high purity hydrogen by using supported palladium membrane reactor as steam reformer. Int.J. Hydrogen Energy 2000 25 211-219. 

Itoh, N. Govind, R. Development of a Novel Oxidative Palladium Membrane Reactor AIChE Symposium Series 268, Govind and Itoh, eds. New York, NY 1989. 

Uemiya, S. Sato, N. Ando, H. Kikuchi, E. The Water Gas Shift Reaction Assisted by a Palladium Membrane Reactor Ind. Eng. Chem. Res. 30 (1991a) 585-589. 

Itoh et al(S). studied dehydrogenation of cyclohexane in a palladium membrane reactor containing a packed bed of Pt/Al203 catalyst. The removal of hydrogen from the reaction mixture using the pal dium membrane increased the conversion from the equilibrium value of 18.7% to as high as 99.5%. It was shown that for given rates of permeation and reaction, there is an optimum thickness of membrane, at which maximum conversion is obtained. 

Recently, Itoh and Govind(ll.) have reported a theoretical study of coupling an exothermic hydrogen oxidation reaction with dehydrogenation of 1-butene in an isothermal palladium membrane reactor. 

A schematic of a palladium membrane reactor is shown in figure 1. The reversible reaction of 1-butene dehydrogenation occurs on the reaction side of the membrane in which the chrome-alumina catalyst is uniformly packed. The oxidation of hydrogen with oxygen in air occurs in the permeation or separation side on the palladium membrane surface. The... 

Figure 11.22 Comparison of plug-flow isothermal and adiabatic palladium membrane reactors for dehydrogenation of 1-butene [Itoh and Govind, 1989]...

Basile, A., Paturzo, L., Lagana, F. (2001). The partial oxidation of methane to syngas in a palladium membrane reactor simulation and experimental studies. Catalysis Today 67,65-75. 

Itoh, N., Kaneko, Y., Igarashi, A. (2002). Efficient hydrogen production via methenol steam reforming by preventing back-permeation of hydrogen in a palladium membrane reactor. Industrial Eng. Chem. Res. 41,4702-4706. 

S. Uemiya, T. Matsuda, and E. Kikuchi, Aromatization of propane assisted by palladium membrane reactor, Chem, Lett, No. 8, 1335 (1990). 

M. Arai, K. Yamada, and Y. Nishiyama, Evolution and separation of hydrogen in the photolysis of water using titania-coated catalytic palladium membrane reactor, 7. Chem, Eng, Jap, 25 761 (1992). 

Bridesell, S.A. and Willms, R.S., Tritium recovery from tritiated water with a two-stage palladium membrane reactor, Fus. Eng. Design, 39-40, 1041, 1998. 

Fig. 6.18. Simplified drawing of a palladium membrane reactor used for the hydrogenation of an alkene.

B.A. Raich and H.C. Foley, Super equilibrium conversion in palladium membrane reactors. Kinetic sensitivity and time dependence. Appl. Cat.A General, 129 (1995) 167. 

S. Uemiya, N. Sato, H. Ando and E. Kikuchi, The water-gas shift reaction assisted by a palladium membrane reactor. Ind. Eng. Chem. Res., 30 (1991) 585. 

Dittmeyer et al. [9] reviewed the applications of a palladium membrane reactor to catalytic dehydrogenation of paraffins. Based on simplified simulation, it was concluded that a beneficial effect of hydrogen removal through the membrane could be offset by strong adsorption of the product olefin on the catalyst surface that would eliminate the active surface sites and effectively slow down the forward reaction rates. Also, it was observed that the long time stability and reactivity of the palladium membranes would require more research. 

Carbon can block permeation and create porosity at higher temperatures, which is detrimental to both membrane stability and permselectivity [76-79], espedaUy in combination with oxygen [71]. Exposure to unsaturated hydrocarbons at elevated temperatures is particularly detrimental [77, 80]. The formation of carbon on both the membrane and catalyst is promoted in palladium membrane reactors because of the selective removal of hydrogen [81], which necessitates the study of membrane, reactant/product gas mixture, and spedahzed catalyst in concert [51, 82]. For example, a Pd75-Cu25 (aU compositions in this chapter are given in... 

K. L. Sessions, Processing tritiated water at the Savannah River Site A production-scale demonstration of a palladium membrane reactor. Fusion Sci. Technol. 2005, 48(1), 91-96. 

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