06/C250
Interacción metal-soporte en catalizadores de Ni sobre alúmina para el reformado seco de metano
Metal-support interaction in Ni-gamma alumina catalysts for dry reforming of methane
Director: GURAYA María Mónica
Correo electrónico: guraya@cab.cnea.gov.ar
Integrantes: ZAMPIERI, Guillermo; ASCOLANI, Hugo; SÁNCHEZ, Miguel; PASTRANA, Gustavo
Resumen Técnico: Se estudiará la interacción metal-soporte en catalizadores de Ni sobre gamma- alúmina preparados por impregnación y por coprecipitación de níquel durante el proceso sol-gel, caracterizados mediante técnicas de análisis de superficies y probados en la reacción de reformado seco de metano. Se pondrá énfasis en el análisis de los siguientes aspectos, en relación a su influencia en la formación de estructuras tipo “aluminato”: - Contenido de Ni, nominal y efectivo, según el método de preparación. - Temperatura de calcinación - Porosidad del sustrato.
Summary: The importance of metal-support interaction has been proved in Ni/alumina catalyst systems. Aluminate- like structures are observed when the preparation conditions favor strong metal-support interaction, but its role and its influence on the characteristics of the catalysts are still under discussion. Combining different surface analysis techniques an exhaustive characterization of the samples is possible. Particularly, the chemical state of Ni atoms, observed directly by XPS, and the thickness of the aluminate-like layer on the Ni particles, derived from depth profiles obtained by AES-ion bombardment cycles, give useful information of the already mentioned metal-support interaction. We will study the Ni-aluminate formation on Ni-alumina catalysts prepared in our laboratory and its influence on the activity and stability of the catalysts in the dry-reforming of methane. For sample preparation, two methods will be followed: impregnation of gamma-alumina and co-precipitation of Ni and gamma-alumina through a sol-gel process. In both cases samples will be prepared with different Ni content, treated under various thermal treatments, and tested against the reaction of dry-reforming of methane. Before and after the catalytic tests a thorough characterization by nitrogen adsorption, DTA-TG, TEM, SEM, XPS and AES-ion bombardment will be performed.