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Amplification of Molecular Traffic Control in catalytic grains with novel channel topology design

Andreas Brzank·Gunter M. Schuetz
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Abstract

We investigate the conditions for reactivity enhancement of catalytic processes in porous solids by use of molecular traffic control (MTC). With dynamic Monte-Carlo simulations and continuous-time master equation theory applied to the high concentration regime we obtain a quantitative description of the MTC effect for a network of intersecting single-file channels in a wide range of grain parameters and for optimal external operating conditions. Implementing the concept of MTC in models with specially designed alternating bimodal channels we find the efficiency ratio (compared with a topologically and structurally similar reference system without MTC) to be enhanced with increasing grain diameter, a property verified for the first time for an MTC system. Even for short intersection channels, MTC leads to a reactivity enhancement of up to approximately 65%. This suggests that MTC may significantly enhance the efficiency of a catalytic process for small as well as large porous particles with a suitably chosen binary channel topology.

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Andreas Brzank, Gunter M. Schuetz. 2005-12-30. Amplification of Molecular Traffic Control in catalytic grains with novel channel topology design. https://doi.org/10.1063/1.2200691

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