Catalytic combustion of dry carbon monoxide by external power activation

The catalytic combustion of dry carbon monoxide and air in a planar stagnation-point flow over a platinum foil with external power is studied in this paper. The reduced heterogeneous kinetics are modelled with the dissociative adsorption of the molecular oxygen and the non-dissociative adsorption of...

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Detalles Bibliográficos
Autores: Prince, JC, Treviño, C
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2000
País:México
Institución:Universidad Nacional Autónoma de México
Repositorio:Sistema de Información de la Facultad de Ciencias, UNAM
OAI Identifier:oai:repositorio.fciencias.unam.mx:11154/3284
Acceso en línea:http://hdl.handle.net/11154/3284
Access Level:acceso abierto
Palabra clave:Chemistry, Physical
Physics, Condensed Matter
carbon monoxide
catalysis
models of surface chemical reactions
surface energy
Descripción
Sumario:The catalytic combustion of dry carbon monoxide and air in a planar stagnation-point flow over a platinum foil with external power is studied in this paper. The reduced heterogeneous kinetics are modelled with the dissociative adsorption of the molecular oxygen and the non-dissociative adsorption of CO, together with a surface reaction of the Langmuir-Hinshelwood type and the desorption reaction of the adsorbed product, CO2(s). The resulting governing equations have been numerically integrated and the whole S-shaped response curve has been obtained as a function of the mixture initial concentration. The critical conditions for the catalytic ignition and extinction are deduced using high activation energy asymptotics of the desorption kinetics of the most efficient adsorbed reactant, CO(s). We obtained a very good agreement between the numerical and asymptotic results for the ignition and extinction conditions. In general, the ignition process can be well modelled without reactant consumption, while extinction occurs in the partial diffusion-controlled regime, with a finite non-zero concentration of carbon monoxide close to the plate. (C) 2000 Published by Elsevier Science B.V. All rights reserved.