Effect of the support composition on the vapor-phase hydrogenation of crotonaldehyde over Pt/CexZr1-xO2 catalysts

Vapor-phase hydrogenation of toluene and selective hydrogenation of crotonaldehyde (2-butenal) have been performed at 333 K over Cl-free Pt/ZrO2 and Pt/CexZr1−xO2 catalysts (0.2⩽x⩽0.8) after reduction under H2 at low (473 K) and high (773 K) temperatures. The catalysts were characterized by X-ray di...

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Detalles Bibliográficos
Autores: Serrano Ruiz, Juan Carlos, Luettich, J., Sepúlveda-Escribano, Antonio, Rodríguez-Reinoso, F.
Tipo de recurso: artículo
Fecha de publicación:2006
País:España
Institución:Universidad Loyola Andalucía
Repositorio:Brújula
OAI Identifier:oai:repositorio.uloyola.es:20.500.12412/5012
Acceso en línea:https://hdl.handle.net/20.500.12412/5012
Access Level:acceso abierto
Palabra clave:Ceria–zirconia mixed oxides
Toluene hydrogenation
Crotonaldehyde hydrogenation
SMSI effect
Pt catalysts
Descripción
Sumario:Vapor-phase hydrogenation of toluene and selective hydrogenation of crotonaldehyde (2-butenal) have been performed at 333 K over Cl-free Pt/ZrO2 and Pt/CexZr1−xO2 catalysts (0.2⩽x⩽0.8) after reduction under H2 at low (473 K) and high (773 K) temperatures. The catalysts were characterized by X-ray diffraction, Raman spectroscopy, temperature-programmed reduction, and X-ray photoelectron spectroscopy after each reduction treatment. An important effect of the support composition on the catalytic activity was observed for both reactions. The catalytic behavior of Pt in the two test reactions studied was strongly dependent on the support composition and on the reduction temperature. For toluene hydrogenation, after reduction at 473 K, catalytic activity was higher for catalysts with no or low ceria content. Furthermore, whereas the increase in the reduction temperature hardly modified the activity of Pt/ZrO2, it strongly deactivated the catalysts with high cerium content in the support. For crotonaldehyde hydrogenation, on the other hand, increased reduction temperature produced a general increase in activity (except for the catalyst with the highest cerium content), along with an increase in selectivity toward the hydrogenation of the carbonyl bond to yield crotyl alcohol. The results are explained on the basis of the effect of partial reduction of Ce(IV) in the support.