Molecular Traffic Control in Porous Nanoparticles

Andreas Brzank; Gunter Schuetz

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Molecular Traffic Control in Porous Nanoparticles

Andreas Brzank·Gunter 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) as a function of reaction rate and grain size. With dynamic Monte-Carlo simulations and continuous-time random walk theory applied to the low 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. The efficiency ratio (compared with a topologically and structurally similar reference system without MTC) is inversely proportional to the grain diameter. However, for small grains MTC leads to a reactivity enhancement of up to approximately 30% of the catalytic conversion $A\to B$ even for short intersecting channels. This suggests that MTC may significantly enhance the efficiency of a catalytic process for small porous nanoparticles with a suitably chosen binary channel topology.

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Andreas Brzank, Gunter Schuetz. 2005-06-29. Molecular Traffic Control in Porous Nanoparticles. https://arxiv.org/abs/cond-mat/0503068

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