Preferential oxidation of CO in presence of H2: behavior of PtSn/y-Al2O3 catalysts modified by K or Ba

The behavior of catalysts based on Pt/y -Al2O3 is analyzed in the CO oxidation reaction. Experiments were performed in the temperature range between 50°C and 250°C with a feed H2 rich, and a concentration of 1% CO and 0.6% O2 Catalysts studied were: monometallic Pt/ y-Al2O3, bimetallic PtSn/ -Al2O3...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Siri, Guillermo Jorge, Bertolini, Guillermo Ramón, Ferretti, Osmar
Formato: Articulo
Lenguaje:Inglés
Publicado: 2007
Materias:
Acceso en línea:http://sedici.unlp.edu.ar/handle/10915/99917
https://ri.conicet.gov.ar/11336/16655
http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S0327-07932007000400008&lng=es&nrm=iso&tlng=en
Aporte de:
Descripción
Sumario:The behavior of catalysts based on Pt/y -Al2O3 is analyzed in the CO oxidation reaction. Experiments were performed in the temperature range between 50°C and 250°C with a feed H2 rich, and a concentration of 1% CO and 0.6% O2 Catalysts studied were: monometallic Pt/ y-Al2O3, bimetallic PtSn/ -Al2O3 with a ratio Sn/Pt=1.6 at/at and two catalysts prepared by modification of the last one with K or Ba. The catalyst that showed maximum activity and selectivity levels is the PtSnK/y -Al2O3. The tin addition increases the activity which allows the reaction to occur at lower temperatures due to the decrease in the CO-Pt interaction. The addition of K or Ba produces a subsequent improvement with respect to the CO oxidation temperature, which leads to a selectivity increase. The selectivity of the CO oxidation passes through a maximum value as a function of the temperature. This maximum is explained by the importance acquired by the reverse of water gas shift reaction at temperatures near 200ºC