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Diffusion and reaction in catalyst pellets with bidisperse pore size distribution
Date
1998-06-01
Author
Doğu, Timur
Metadata
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Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License
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Catalysts with bidisperse pore structures are extensively used in chemical industries. In such catalysts, diffusion and reaction in the microporous particles are preceded by diffusion in the macropores. The relative significance of macro-and micropore diffusion resistances on the observed reaction rates with Linear and nonlinear rate forms, heat effects, catalyst deactivation and selectivity problems in bidisperse catalysts are investigated in number of published works. In this article, a review of the models proposed in the literature is presented together with a critical analysis of assumptions involved. Criteria are presented to test the relative significance of transport limitations. Also, a review of experimental techniques and experimental values of micro-and macropore effective diffusivities of gases in solids with bidisperse pore structures, such as zeolite pellets and supported porous catalysts, is given.
Subject Keywords
Shape normalization
,
Restrictive diffusion
,
Network model
,
Sorption kinetics
,
Gas-chromatography
,
Micropore Diffusion;
,
Mass-transfer
,
Porous catalysts
,
Ion-exchange resin
,
Frequency-response method
URI
https://hdl.handle.net/11511/62328
Journal
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
Collections
Graduate School of Natural and Applied Sciences, Article
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T. Doğu, “Diffusion and reaction in catalyst pellets with bidisperse pore size distribution,”
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
, pp. 2158–2171, 1998, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/62328.