Hydrogen palladium membrane reactor

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. 

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. 

The use of a membrane reactor for shifting equilibrium controlled dehydrogenation reactions results in increased conversion, lower reaction temperatures and fewer byproducts. Results will be presented on a palladium membrane reactor system for dehydrogenation of 1-butene to butadiene, with oxidation of permeating hydrogen to water on the permeation side. The heat released by the exothermic oxidation reaction is utilized for the endothermic dehydrogenation reaction. 

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... 

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. 

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). 

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

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... 

Then Uemiya et al. [2] reported another Pd membrane reactor for WGS reaction using Fe-Cr oxide catalysts. The model of flow in the palladium membrane reactor is illustrated in Figure 6.3. They proposed that hydrogen is permeated through palladium membrane via a solution diffusion transport mechanism, and the rate of hydrogen permeation, /, per unit area of membrane, is written in terms of Fick s first law as follows ... 

A. S. Augustine, Y. H. Ma, N. K. Kazantzis, High pressure palladium membrane reactor for the high temperature wateregas shift reaction, Int. J. Hydrogen Energy 36 (2011) 5359-5360. 

M. Abdollahia, J. Yua, P. K. T. Liub, R. Ciorab, M. Ahimia, T. T. Tsotsis, Ultra-pure hydrogen production from reformate mixtures using a palladium membrane reactor system, J. Membr. Sci. 390-391 (2012) 32-A2. 

Itoh, N., Tamura, E., Hara, S., Takahashi, T., Shono, A., Satoh, K. and Namba, T., 2003. Hydrogen Recovery from Cyclohexane as a Chemical Hydrogen Carrier Using a Palladium Membrane Reactor. Catalysis Today, 82(1-4) 119-125. 

Chen Y, Wang Y, Xu H, Xiong G (2008) Efficient production of hydrogen from natural gas steam reforming in palladium membrane reactor. Appl Catal B 80 283-294... 

Van Delft YC, Correia LA et al. (2007) Palladium membrane reactors for large scale production of hydrogen. 8th international conference of catalysis in membrane reactors, December 18-21 Kolkata (India)... 

Y. C. Van Delft and L. A. Correia, Palladium Membrane Reactors for Large Scale Production of Hydrogen, 8th International Conference of Catalysis in Membrane Reactors, 18-21 December 2007, Kolkata, India. 

Kara, S., Sakaki, K. and Itoh, N. (1999) Decline in Hydrogen Permeation Due to Concentration Polarization and CO Hindrance in a Palladium Membrane Reactor. Industrial and Engineering Chemistry Research, 38,4913 918. 

Basile, A., Pinacci, P., lulianelli, A. et al. (2011) Ethanol steam reforming reaction in a porous stainless steel supported palladium membrane reactor. International Journal of Hydrogen Energy, 36,2029-2037. 

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