Zeolite membrane reactors applications

Hong, M., R.D. Noble, and J.L. Falconer, Highly selective H2 Separation Zeolite Membranes for Coal Gasification Membrane Reactor Applications, Annual Technical Progress Report, U.S. DOE Contract DE-FG26-02NT41536, December 2005. 

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. 

The insertion of catalytically active guests, such as transition metal ions, is an example of the potentialities of zeolite membranes for applications in catalytic membrane reactors. The well-known catalytic properties of supported vanadium oxides for selective oxidations have recently prompted a number of studies on the possibility of inserting vanadium in the framework of crystalline microporous silica and aluminosilicate powders. " ... 

Nevertheless, the development of zeolite-membrane reactors still requires improvements in the fluxes and separation factors attained to date, an objective to which many efforts have been devoted in recent years with the aim of materializing an industrial application of zeolite-membrane reactors. Several reviews have been published in the last 5 years dealing completely or partially with zeolite membranes [2,3,5,161,162,165-167]. Particularly, noteworthy have been the advances regarding the use of supports of different natures and characteristics (see Section 10.6.4), the control of the orientation and thickness of zeolite layers (see Section 10.2.1.2), and the preparation of new zeolite materials such as membranes (see Section 10.3). In spite of these advances, before zeolite-membrane reactors are used in industry (see Section 10.6.5), signihcant progress must be achieved in more prosaic issues such as scale-up and control of the synthesis process to increase membrane reproducibility. 

It has been considered traditional applications of zeolite-membrane reactors those based on reactor concepts already demonstrated using mesoporous or dense membranes. These include conversion enhancement by equilibrium displacement or by the removal of inhibitors, and selectivity enhancement by reactant distribution. For such cases, the zeolite membrane is usually catalytically inert and is coupled with a conventional fixed bed of catalyst placed on one of the membrane sides. 

New Applications of Zeolite-Membrane Reactors Microchemical Systems... 

Giroir-Fendler A, Julbe A, Ramsay JDF, and Dalmon JA. CNRS French Patent, PCT Int Appl. FR 94-5562, 940429. 1994. Giroir-Fendler A, Peureux J, Mozzanega H, and Dalmon JA. Characterization of a zeolite membrane for catalytic membrane reactor application. Stud Surf Sci Catal A 1996 101 127-136. 

Piera E, TeUez C, Coronas J, Menendez M, and Santamarfa J. Use of zeolite membrane reactors for selectivity enhancement Application to the liquid-phase oligomerization of i-butene. Catal Today 2001 67 127-138. 

F. Kapteijn, W. Zhu, J.A. Moulijn, T.Q. Gardner, Zeolite Membranes - Modelling, Application. In A. Cybulski J.A. Moulijn (Eds), Structured Catalysts and Reactors Second Edition, Revised and Expanded. Marcel Dekker, New York, NY, 2005. 

This chapter gives an overview of the synthesis procedures and applications of zeolite membranes (gas separation, pervaporation, and zeolite-membrane reactors), as well as new emerging applications in the micro- and nanotechnology field. It is important to note that, up to now, pervaporation is the only large-scale industrial application and gas separation is still not implemented at industrial level for zeolite membranes. Related areas such as new zeolite and zeolite-related materials for membranes, alternative supports, and scale-up issues are also discussed. 

Zeolite-Membrane Reactors for Selectivity Enhancement by Control of Reactant Traffic A Not-So-Classic Application... 

Giroir-Fendler A, Peureux J, Mozzanega H, Dahnon JA. Characterization of a zeolite membrane for Catalytic Membrane Reactor application. Stud Surf Sci Catal A 1996 101 127-136. 

Van de Graaf JM, Zwiep M, Kapteijn F, Moulijn JA (1999) Application of a zeolite membrane reactor in the metathesis of propene. Chem Eng Sci 54 1441-1445... 

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