INCAPE   05401
INSTITUTO DE INVESTIGACIONES EN CATALISIS Y PETROQUIMICA "ING. JOSE MIGUEL PARERA"
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Estudio del mecanismo de conversión de CO (WGS) sobre catalizadores basados en Pt mediante técnica DRIFT
Autor/es:
CH. VIGNATTI; C.R. APESTEGUÍA; T.F. GARETTO
Lugar:
Buenos Aires
Reunión:
Congreso; XVI Congreso Argentino de Catálisis; 2009
Resumen:
The water gas shift reaction was studied on Pt supported on reducible (CeO2 and TiO2) and non-reducible oxides (SiO2). All the catalysts were prepared by incipient wetness impregnation. The CO conversion turnover rate was 1-2 orders of magnitude higher on platinum supported on reducible oxides (CeO2 and TiO2) than on Pt/SiO2. The most active catalyst was Pt/TiO2 of high specific surface area. The chemical species formed on Pt/CeO2 and Pt/TiO2 during the WGS reaction were identified by DRIFT. Results showed that the reaction occurs via the interaction between CO and hydroxyl groups of the support, with formation of formate intermediates. The intensity of formate bands was lower on Pt/TiO2 catalysts than on Pt/CeO2. The lower stability of formate intermediates on Pt/TiO2 would explain the higher activity displayed by these catalysts. No formate bands were detected on Pt/SiO2, thereby suggesting that the WGS reaction on this catalyst occurs via a redox mechanism.2 and TiO2) and non-reducible oxides (SiO2). All the catalysts were prepared by incipient wetness impregnation. The CO conversion turnover rate was 1-2 orders of magnitude higher on platinum supported on reducible oxides (CeO2 and TiO2) than on Pt/SiO2. The most active catalyst was Pt/TiO2 of high specific surface area. The chemical species formed on Pt/CeO2 and Pt/TiO2 during the WGS reaction were identified by DRIFT. Results showed that the reaction occurs via the interaction between CO and hydroxyl groups of the support, with formation of formate intermediates. The intensity of formate bands was lower on Pt/TiO2 catalysts than on Pt/CeO2. The lower stability of formate intermediates on Pt/TiO2 would explain the higher activity displayed by these catalysts. No formate bands were detected on Pt/SiO2, thereby suggesting that the WGS reaction on this catalyst occurs via a redox mechanism.