Diffusion and Reaction in Catalytic Monolith Washcoat - Modeling Approaches

To model properly the effects of varying washcoat thickness, distribution of noble metals and other catalyst components on ignition phenomena and conversion a detailed description of processes inside the catalytic washcoat layer is necessary. In this contribution we first discuss the spatially 2D (1D+1D) model of entire monolith with effective internal diffusion. Then we describe detailed, spatially 3D model using digital reconstruction of a section of porous catalytic washcoat on a micro- and nano-scale. We briefly describe suitable numerical procedures for solution of such models and coupling of the models on different levels. We illustrate the methodology on examples of oxidation catalyst and NOx storage & reduction catalyst.

References:

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