Effect of CO2, H2O and SO2 in the ceria-catalyzed combustion of soot under simulated diesel exhaust conditions

Por favor, use este identificador para citar o enlazar este ítem: http://hdl.handle.net/10045/37700
Información del item - Informació de l'item - Item information
Título: Effect of CO2, H2O and SO2 in the ceria-catalyzed combustion of soot under simulated diesel exhaust conditions
Autor/es: Hernández Giménez, Ana M. | Lozano Castelló, Dolores | Bueno López, Agustín
Grupo/s de investigación o GITE: Materiales Carbonosos y Medio Ambiente
Centro, Departamento o Servicio: Universidad de Alicante. Departamento de Química Inorgánica | Universidad de Alicante. Instituto Universitario de Materiales
Palabras clave: Diesel soot | Soot combustion | Ceria–zirconia catalyst | Neodymium–ceria catalyst | Nitrogen oxides
Área/s de conocimiento: Química Inorgánica
Fecha de publicación: 27-abr-2014
Editor: Elsevier
Cita bibliográfica: Applied Catalysis B: Environmental. 2014, 148-149: 406-414. doi:10.1016/j.apcatb.2013.11.029
Resumen: The effect of CO2, H2O and SO2 in the Ce0.73Zr0.27O2 and Ce0.64Zr0.27Nd0.09O2 catalyzed combustion of soot with NOx + O2 has been studied. Combustion experiments performed in a fix-bed reactor with soot-catalyst mixtures prepared in loose contact mode showed that CO2, H2O and SO2 lower the activity of both catalysts, and the inhibiting effect follows the trend SO2 > H2O > CO2. Regardless the gas mixture composition, the catalytic activity for soot combustion of Ce0.64Zr0.27Nd0.09O2 is equal or higher to that of Ce0.73Zr0.27O2 because Nd3+ doping seems to promote the participation of the active oxygen mechanism together with the NO2-assisted mechanism in the catalytic combustion of soot. The maximum soot combustion rate achieved during a Ce0.64Zr0.27Nd0.09O2-catalyzed reaction in NOx/O2/CO2/H2O/N2 is about three times higher than that of the uncatalyzed combustion, and this catalyst also improves the CO2 selectivity. In situ DRIFTS experiments showed that CO2, H2O and SO2 compete with NOx for the adsorption sites on the catalysts’ surface. CO2 partially impedes the catalytic oxidation of NO to NO2, affecting much more to the Nd3+-containing catalyst; however, the contribution of the active oxygen mechanism seems to remain relevant in this case. H2O also hinders the catalytic oxidation of NO to NO2 on both catalysts, and therefore the catalytic combustion of soot, because delays the formation of nitrogen reaction intermediates on the catalysts’ surface and favors the formation of more stable nitrogen surface species than in a H2O-free gas stream. For both catalysts, SO2 chemisorption (with sulfate formation) is even able to remove nitrogen surface groups previously formed by NOx chemisorption, which significantly inhibits the catalytic oxidation of NO to NO2 and the catalytic combustion of soot.
Patrocinador/es: Financial support of Generalitat Valenciana (Project Prometeo 2009/047), the Spanish Ministry of Economy and Competitiveness (Project CTQ2012-30703), and the UE (FEDER funding).
URI: http://hdl.handle.net/10045/37700
ISSN: 0926-3373 (Print) | 1873-3883 (Online)
DOI: 10.1016/j.apcatb.2013.11.029
Idioma: eng
Tipo: info:eu-repo/semantics/article
Revisión científica: si
Versión del editor: http://dx.doi.org/10.1016/j.apcatb.2013.11.029
Aparece en las colecciones:INV - MCMA - Artículos de Revistas

Archivos en este ítem:
Archivos en este ítem:
Archivo Descripción TamañoFormato 
Thumbnail2014_Hernandez-Gimenez_etal_ACBE.pdfVersión final (acceso restringido)1,93 MBAdobe PDFAbrir    Solicitar una copia
Thumbnail2014_Hernandez-Gimenez_etal_ACBE_Accepted-manuscript.pdfVersión revisada (acceso abierto)1,2 MBAdobe PDFAbrir Vista previa


Todos los documentos en RUA están protegidos por derechos de autor. Algunos derechos reservados.