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Molecular Diffusion Processes in Crystalline Microporous Materials

Published online by Cambridge University Press:  10 February 2011

G. Sastre
Affiliation:
Davy Faraday Research Laboratory, The Royal Institution of Great Britain, 21, Albemarle Street. WIX 4BS, London, U.K. Instituto de Tecnologia Quimica, UPV-CSIC. Av/ Naranjos s/n. 46022 Valencia, Spain
A. Corma
Affiliation:
Instituto de Tecnologia Quimica, UPV-CSIC. Av/ Naranjos s/n. 46022 Valencia, Spain
C. R. A. Catlow
Affiliation:
Davy Faraday Research Laboratory, The Royal Institution of Great Britain, 21, Albemarle Street. WIX 4BS, London, U.K.
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Abstract

Atomistic Molecular Dynamics are used to simulate diffusion of hydrocarbons inside the microporous structure of siliceous zeolite CIT-I, with chemical composition SiO2. CIT-1 is a crystalline microporous material containing channels formed by rings containing 12 and 10 Si atoms (Figure 1). The dimensions of these two channel systems are sufficient to cause substantial differences in the diffusion of para-xylene and ortho-xylene. Diffusion coefficients as a function of loading of each isomer, and activation energies have been calculated from the simulations. The effect of the isomer size in the diffusion path is also analysed.

Type
Research Article
Copyright
Copyright © Materials Research Society 1998

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