Ceramic membrane reactors

Fig. 4. Configuration of a ceramic membrane reactor for partial oxidation of methane. The membrane tube, with an outside diameter of about 6.5 mm and a length of up to about 30 cm and a wall thickness of 0.25-1.20 mm, was prepared from an electronic/ionic conductor powder (Sr-Fe-Co-O) by a plastic extrusion technique. The quartz reactor supports the ceramic membrane tube through hot Pyrex seals. A Rh-containing reforming catalyst was located adjacent to the tube (57).

Fig. 5. Methane conversion and oxygen flux during partial oxidation of methane in a ceramic membrane reactor. Reaction conditions pressure, 1 atm temperature, 1173 K, feed gas molar ratio, CH Ar = 80/20 feed flow rate, 20 mL min-1 (NTP) catalyst mass, 1.5 g membrane surface area, 8.4 cm2 (57).

Fig. 6. Configuration of a ceramic membrane reactor for partial oxidation of methane. The membrane disk was prepared by pressing Bao.5Sro.5Coo.8Feo.2O3-s oxide powder in a stainless steel module (17 mm inside diameter) under a pressure of (1.3-1.9) X 109 Pa. The effective area of the membrane disk exposed to the feed gas (CH4) was 1.0 cm2 (72).

P.N. Dyer, C.M. Chen, Engineering development of ceramic membrane reactor system for converting natural gas to H2 and syngas for liquid transportation fuel, Proceedings of the 2000 Hydrogen Program Review, DOE, 2000... 

Development of Ceramic Membrane Reactor Systems for Converting Natural Gas to Hydrogen and Synthesis Gas for Liquid Transportation Fuels, Proceedings of the 2002 U.S. DOE Hydrogen Program Review, NREL/CP-610-32405, Washington, D.C., 2002. 

Champagnie, A.M., T.T. Tsotsis, R.G. Minet and I.A. Webster, 1990b, Studies of ethane dehydrogenation in a ceramic membrane reactor, presented at Int. Congr. Membr. Membr. Proc., Chicago, IL, USA. 

Single tubular membrane reactors are often used in experimental and feasibility studies. Its justification for use in production environments can sometimes be made in small volume applications. As mentioned in Chapters 4 and 5, inorganic composite membranes consist of multiple layers. The inner most layer in a tubular composite membrane reactor does not necessarily possess the finest pores. For example, a two>layered tubular ceramic membrane reactor used for enzymatic reactions has an inner layer containing pores larger than those in the outer layer [Lillo, 1986]. The pores of the inner layer are immobilized with enzymes. Under the influence of an applied pressure difference across the membrane matrix, a solution entering the hollow central core of the tube Hows into the inner layer where the solution reacts with the enzyme. The product which is smaller than the enzyme passes through the permselective outer layer membrane which retains the enzyme. Thus the product is removed from the reaction mixture. 

Since membrane reactors based on metal membranes have been thoroughly addressed in the previous chapter, attention hereafter is paid mostly to ceramic-membrane reactors, elucidating their basic features and application opportunities, and updating to June 1995 the literature information given in other recent reviews [11,12]. 

Coronas J., Menendez M. and Santamaria J., Methane oxidative coupling using porous ceramic membrane reactors. Part II. Reaction studies, Chem. Engng. Sci. 49 2015 (1994). Coronas J., Menendez M. and Santamaria J., Development of ceramic membrane reactors with non-uniform permeation pattern. Application to methane oxidative coupling, Chem. Eng. Sci. 49 4749 (1994). 

Lafaiga D., Santamaria J. and Menendez M., Methane oxidative coupling using porous ceramic membrane reactors. Part I. Reactor development, Chem. Eng. ScL 49 2005 (1994). Sloot H.J., Smolders C.A., van Swaaij W.P.M. and Versteeg G.F., High-temperature membrane reactor for catalytic gas-solid reactions, AIChE J. J5 887 (1992). 

Kamoshita Y, Ohashi R, and Suuzuki T. Improvement of filtration performance of stirred ceramic membrane reactor and its application to rapid fermentation of lactic acid by dense cell culture of Lactoccus lactis. J. Ferment. Bioeng. 1998 85(4) 422 27. 

Yu, W., Ohmori, T., Yamamoto, T., Endo, A., Nakaiwa, M., Hayakawa, T., and Itoh, N. Simulation of a porous ceramic membrane reactor for hydrogen production. International Journal of Hydrogen Energy, 2005, 30 (10), 1071. 

S. Pei, M.S. Kleefisch, T.P. Kobylinski, K. Faber, C.A. Udovich, V. Zhang-McCoy, B. Dabrowski, U. Balachandran, R.L. Mieville and R.B. Poeppel, Failure mechanisms of ceramic membrane reactors in partial oxidation of methane to synthesis gas. Catal. Lett., 30 (1995) 210-212. 

A.D. Davidson and M. Salim, Initial studies of a novel ceramic membrane reactor. Br. Ceram. Proc., 119 (1988) 43. 

R.G. Minet, S.P. Vasileiadis and T.T. Tsotsis, Experimental studies of a ceramic membrane reactor for the steam/methane reaction at moderate temperatures 400-700 C, in G.A. Huff and D.A. Scarpiello (Eds.), Proceedings of the Symposium on Natural Gas Upgrading, 37 (1992) 245. 

D. Lafarga, J. Santamaria and M. Menendez, Methane oxidative coupling using porous ceramic membrane reactors. I. Reactor development. Chem. Eng. Sci., 49 (1994) 2005. 

Permeation characteristics of Knudsen diffusion membranes, consisting of a support and two consecutive layers, have been used to calculate the performance of the ceramic membrane reactor, see also Section 14.2.1 [17,31]. The pore size of the separation layer of these membranes is 4 nm in diameter [31,38]. Ideal membranes which remove all the hydrogen formed do not exist (possible Pd-based membranes will come close to the required characteristics), but are used as a basis for calculating the maximum possible increase in conversion and selectivity. 

Two process flow diagrams have been developed for a ceramic membrane reactor process ... 

It is concluded that a ceramic membrane reactor based on Knudsen diffusion membranes can give improvements in an isothermal reactor concept although the difference in price level between feedstock and product is too small to give an economically viable process. 

The packed bed ceramic membrane reactor configuration (PBMR) has been chosen as the reactor set-up (see Section 14.2.2). In the PBMR configuration three possible sub-configurations can be envisioned for a specific sweep gas in combination with a hydrogen or oxygen selective membrane for the dehydrogenation of ethylbenzene. These sub-configurations are shown in Fig. 14.10. 

Technical and economic evaluation study for the use of ceramic membrane reactors for the dehydrogenation of propane to propylene. Confidential NOVEM Report No. 33105/0090, by KTl, ECN and HlC, Jan. 1994. 

Large-pore" materials are becoming important in some industrial applications catalytic processes for selective oxidation, hydrodesulfurization, steam reforming inorganic ceramic membrane reactors supports for high performance liquid chromatography, etc. 

M. Schwartz, J.H. White, M.G. Myers, S. Deych, and A.F. Sammels, in "The Use of Ceramic Membrane Reactors for the Partial Oxidation of Methane to Synthesis Gas", Preprints 213th ACS National Meeting, San Francisco, CA, April 13-17, 42, 1997. 

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