Quantifying Diffusion‐limited Catalytic Reactions in Hierarchically Structured Porous Materials by Combining Kinetic Monte Carlo Simulations with the Two‐region Model of Diffusion. Issue 21 (13th October 2022)

• Record Type: Journal Article
• Authors: Hwang, Seungtaik; Schneider, Daniel; Haase, Jürgen; Miersemann, Erich; Kärger, Jörg
• Is Part Of: ChemCatChem. Volume 14:Issue 21(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-10-13
• Subjects: diffusion, pore hierarchies -- catalytic conversion -- effectiveness factor -- two-region model; Catalysis -- Periodicals; 541.39505
• DOI: 10.1002/cctc.202200829
• Languages: English
• ISSNs: 1867-3880

Abstract

Abstract: The use of hierarchically organized nanoporous materials has proven to be well suited for counteracting transport hindrance in micropores and the resulting reduction in their technological performance. As a typical example, we consider materials with the structure of mesoporous zeolites, where a microporous continuum is traversed by a network of mesopores. Mass transfer in such material has recently been shown to be effectively quantitated by application of the two‐region approach of diffusion (the "Kärger model"). It operates with the diffusivities in the two pore spaces, their relative occupations and the mutual exchange rates as the only free parameters. In the present paper, the validity of this approach for the combined consideration of mass transfer and catalytic conversion in such materials will be confirmed by comparison with the outcome of kinetic Monte Carlo simulations. Abstract : The usefulness of the "two‐region approach" (the "Kärger model") for quantifying the combined influence of diffusion and reaction in hierarchically structured porous catalysts is confirmed by comparison with the results of kinetic Monte Carlo simulations, paving the way to handy expressions for both the uptake and release times and the effectiveness factor of catalytic conversion.