Selective CO methanation with structured RuO2/Al2O3 catalysts

Active and selective structured RuO/AlO catalysts for CO methanation using a flow simulating CO-rich reformate gases from WGS and PROX units (H excess, CO presence and 300 ppm CO concentration) were prepared. Both, the RuO/AlO powder and the slurry prepared from it for its structuration by washcoati...

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Detalles Bibliográficos
Autores: Muñoz-Murillo, A., Martínez, L.M., Domínguez, M. I., Odriozola, José Antonio, Centeno, Miguel Ángel
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2018
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/169951
Acceso en línea:http://hdl.handle.net/10261/169951
Access Level:acceso abierto
Palabra clave:RuO2/Al2O3 catalysts
CO2 methanation
CO methanation
Washcoating
Metallic micromonolith
Descripción
Sumario:Active and selective structured RuO/AlO catalysts for CO methanation using a flow simulating CO-rich reformate gases from WGS and PROX units (H excess, CO presence and 300 ppm CO concentration) were prepared. Both, the RuO/AlO powder and the slurry prepared from it for its structuration by washcoating of the metallic micromonolithic structure, were also active and selective. Both the slurry (S-RuAl) and micromonoliths (M-RuAl) were able to completely and selectively methanate CO at much lower temperatures than the parent RuAl powder. The optimal working temperature in which the CO conversion is maximum and the CO conversion is minimized was determined to be from 149 °C to 239 °C for S-RuAl and from 165 °C to 232 °C for M-RuAl, whilst it was from 217 °C to 226 °C for RuAl powder. TPR, XRD and TEM measurements confirmed that the changes in the activity and selectivity for CO methanation among the considered catalysts can be related with modifications in the surface particle size of ruthenium and its reducibility. These were ascribed to the metallic substrate, the presence of PVA and colloidal alumina in the slurry preparation, the aqueous and acidic media and the thermal treatment used, resulting in a more active and selective catalysts than the parent powder.