Zeolite micromembranes

The benefits of the use of micromembranes for the selective removal of one or more products during reaction have been demonstrated for equdibrium-limited reactions [289]. For example, the performance of hydrophilic ZSM-5 and NaA membranes over multichannel microreactors prepared from electro-discharge micromachining of commercial porous stainless steel plates was studied by Yeung et al. in the Knoevenagel condensation [290,291] and andine oxidation to azoxybenzene [292]. For such kind of reactions, the zeolite micromembrane role consists of the selective removal of water, which indeed yields higher conversions, better product purity, and a reduction in catalyst deactivation in comparison to the traditional packed bed reactor. 

Leung YLA and Yeung KL. Microfabricated ZSM-5 zeolite micromembranes. Chem Eng Sci 2004 59 4809-4817. 

E. Mateo, R. Lahoz, X. de la Puente, A. Paniagua, J. Coronas, J. Santamaria, Preparation of silicalite micromembranes on laser perforated stainless steel sheets in Proc. 3rd Int. Zeolite Membrane Meeting, R. Noble (Ed), Breckenridge, CO USA, July 25-28, 2004. 

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