CETMIC   05378
CENTRO DE TECNOLOGIA DE RECURSOS MINERALES Y CERAMICA
Unidad Ejecutora - UE
artículos
Título:
Influence of the support treatment on the Behavior of MnOx/Al2O3 Catalysts used in VOC Combustion
Autor/es:
FABIOLA N. AGÜERO, ALBERTO SCIAN, BIBIANA P. BARBERO AND LUIS E. CADUS
Revista:
CATALYSIS LETTERS
Editorial:
Springer
Referencias:
Año: 2009 vol. 128 p. 268 - 280
ISSN:
1011-372X
Resumen:
Abstract Alumina was treated with water and diluted nitric acid and then was used to prepare supported MnOx/ Al2O3 catalysts with two different loadings. The influence of the support treatment on the catalytic behavior in ethanol and toluene combustion was studied. The treatments modified the alumina physicochemical properties (porosity, surface area, isoelectric point, and surface acidity). The modification of these properties affected the interaction of the manganese oxide species with the support and increased the dispersion of the active phase. Catalysts prepared from treated supports showed the best catalytic performance in ethanol combustion. At high manganese loading, this better catalytic performance was related to the high capacity for adsorbing oxygen. While at low manganese loading, the great amount of dispersed surface manganese oxide species and/or the existence of surface defects were relevant in the catalytic activity. On the other hand, the reactivity of the catalysts in toluene combustion was roughly correlated with the reducibility of the surface manganese oxide species. On the basis of these observations, we conclude that the ethanol combustion occurs by a suprafacial mechanism whereas the toluene combustion proceeds through an intrafacial mechanism. of the support treatment on the catalytic behavior in ethanol and toluene combustion was studied. The treatments modified the alumina physicochemical properties (porosity, surface area, isoelectric point, and surface acidity). The modification of these properties affected the interaction of the manganese oxide species with the support and increased the dispersion of the active phase. Catalysts prepared from treated supports showed the best catalytic performance in ethanol combustion. At high manganese loading, this better catalytic performance was related to the high capacity for adsorbing oxygen. While at low manganese loading, the great amount of dispersed surface manganese oxide species and/or the existence of surface defects were relevant in the catalytic activity. On the other hand, the reactivity of the catalysts in toluene combustion was roughly correlated with the reducibility of the surface manganese oxide species. On the basis of these observations, we conclude that the ethanol combustion occurs by a suprafacial mechanism whereas the toluene combustion proceeds through an intrafacial mechanism. Al2O3 catalysts with two different loadings. The influence of the support treatment on the catalytic behavior in ethanol and toluene combustion was studied. The treatments modified the alumina physicochemical properties (porosity, surface area, isoelectric point, and surface acidity). The modification of these properties affected the interaction of the manganese oxide species with the support and increased the dispersion of the active phase. Catalysts prepared from treated supports showed the best catalytic performance in ethanol combustion. At high manganese loading, this better catalytic performance was related to the high capacity for adsorbing oxygen. While at low manganese loading, the great amount of dispersed surface manganese oxide species and/or the existence of surface defects were relevant in the catalytic activity. On the other hand, the reactivity of the catalysts in toluene combustion was roughly correlated with the reducibility of the surface manganese oxide species. On the basis of these observations, we conclude that the ethanol combustion occurs by a suprafacial mechanism whereas the toluene combustion proceeds through an intrafacial mechanism. of the support treatment on the catalytic behavior in ethanol and toluene combustion was studied. The treatments modified the alumina physicochemical properties (porosity, surface area, isoelectric point, and surface acidity). The modification of these properties affected the interaction of the manganese oxide species with the support and increased the dispersion of the active phase. Catalysts prepared from treated supports showed the best catalytic performance in ethanol combustion. At high manganese loading, this better catalytic performance was related to the high capacity for adsorbing oxygen. While at low manganese loading, the great amount of dispersed surface manganese oxide species and/or the existence of surface defects were relevant in the catalytic activity. On the other hand, the reactivity of the catalysts in toluene combustion was roughly correlated with the reducibility of the surface manganese oxide species. On the basis of these observations, we conclude that the ethanol combustion occurs by a suprafacial mechanism whereas the toluene combustion proceeds through an intrafacial mechanism. nitric acid and then was used to prepare supported MnOx/ Al2O3 catalysts with two different loadings. The influence of the support treatment on the catalytic behavior in ethanol and toluene combustion was studied. The treatments modified the alumina physicochemical properties (porosity, surface area, isoelectric point, and surface acidity). The modification of these properties affected the interaction of the manganese oxide species with the support and increased the dispersion of the active phase. Catalysts prepared from treated supports showed the best catalytic performance in ethanol combustion. At high manganese loading, this better catalytic performance was related to the high capacity for adsorbing oxygen. While at low manganese loading, the great amount of dispersed surface manganese oxide species and/or the existence of surface defects were relevant in the catalytic activity. On the other hand, the reactivity of the catalysts in toluene combustion was roughly correlated with the reducibility of the surface manganese oxide species. On the basis of these observations, we conclude that the ethanol combustion occurs by a suprafacial mechanism whereas the toluene combustion proceeds through an intrafacial mechanism. of the support treatment on the catalytic behavior in ethanol and toluene combustion was studied. The treatments modified the alumina physicochemical properties (porosity, surface area, isoelectric point, and surface acidity). The modification of these properties affected the interaction of the manganese oxide species with the support and increased the dispersion of the active phase. Catalysts prepared from treated supports showed the best catalytic performance in ethanol combustion. At high manganese loading, this better catalytic performance was related to the high capacity for adsorbing oxygen. While at low manganese loading, the great amount of dispersed surface manganese oxide species and/or the existence of surface defects were relevant in the catalytic activity. On the other hand, the reactivity of the catalysts in toluene combustion was roughly correlated with the reducibility of the surface manganese oxide species. On the basis of these observations, we conclude that the ethanol combustion occurs by a suprafacial mechanism whereas the toluene combustion proceeds through an intrafacial mechanism. Al2O3 catalysts with two different loadings. The influence of the support treatment on the catalytic behavior in ethanol and toluene combustion was studied. The treatments modified the alumina physicochemical properties (porosity, surface area, isoelectric point, and surface acidity). The modification of these properties affected the interaction of the manganese oxide species with the support and increased the dispersion of the active phase. Catalysts prepared from treated supports showed the best catalytic performance in ethanol combustion. At high manganese loading, this better catalytic performance was related to the high capacity for adsorbing oxygen. While at low manganese loading, the great amount of dispersed surface manganese oxide species and/or the existence of surface defects were relevant in the catalytic activity. On the other hand, the reactivity of the catalysts in toluene combustion was roughly correlated with the reducibility of the surface manganese oxide species. On the basis of these observations, we conclude that the ethanol combustion occurs by a suprafacial mechanism whereas the toluene combustion proceeds through an intrafacial mechanism. of the support treatment on the catalytic behavior in ethanol and toluene combustion was studied. The treatments modified the alumina physicochemical properties (porosity, surface area, isoelectric point, and surface acidity). The modification of these properties affected the interaction of the manganese oxide species with the support and increased the dispersion of the active phase. Catalysts prepared from treated supports showed the best catalytic performance in ethanol combustion. At high manganese loading, this better catalytic performance was related to the high capacity for adsorbing oxygen. While at low manganese loading, the great amount of dispersed surface manganese oxide species and/or the existence of surface defects were relevant in the catalytic activity. On the other hand, the reactivity of the catalysts in toluene combustion was roughly correlated with the reducibility of the surface manganese oxide species. On the basis of these observations, we conclude that the ethanol combustion occurs by a suprafacial mechanism whereas the toluene combustion proceeds through an intrafacial mechanism. Alumina was treated with water and diluted nitric acid and then was used to prepare supported MnOx/ Al2O3 catalysts with two different loadings. The influence of the support treatment on the catalytic behavior in ethanol and toluene combustion was studied. The treatments modified the alumina physicochemical properties (porosity, surface area, isoelectric point, and surface acidity). The modification of these properties affected the interaction of the manganese oxide species with the support and increased the dispersion of the active phase. Catalysts prepared from treated supports showed the best catalytic performance in ethanol combustion. At high manganese loading, this better catalytic performance was related to the high capacity for adsorbing oxygen. While at low manganese loading, the great amount of dispersed surface manganese oxide species and/or the existence of surface defects were relevant in the catalytic activity. On the other hand, the reactivity of the catalysts in toluene combustion was roughly correlated with the reducibility of the surface manganese oxide species. On the basis of these observations, we conclude that the ethanol combustion occurs by a suprafacial mechanism whereas the toluene combustion proceeds through an intrafacial mechanism. of the support treatment on the catalytic behavior in ethanol and toluene combustion was studied. The treatments modified the alumina physicochemical properties (porosity, surface area, isoelectric point, and surface acidity). The modification of these properties affected the interaction of the manganese oxide species with the support and increased the dispersion of the active phase. Catalysts prepared from treated supports showed the best catalytic performance in ethanol combustion. At high manganese loading, this better catalytic performance was related to the high capacity for adsorbing oxygen. While at low manganese loading, the great amount of dispersed surface manganese oxide species and/or the existence of surface defects were relevant in the catalytic activity. On the other hand, the reactivity of the catalysts in toluene combustion was roughly correlated with the reducibility of the surface manganese oxide species. On the basis of these observations, we conclude that the ethanol combustion occurs by a suprafacial mechanism whereas the toluene combustion proceeds through an intrafacial mechanism. Al2O3 catalysts with two different loadings. The influence of the support treatment on the catalytic behavior in ethanol and toluene combustion was studied. The treatments modified the alumina physicochemical properties (porosity, surface area, isoelectric point, and surface acidity). The modification of these properties affected the interaction of the manganese oxide species with the support and increased the dispersion of the active phase. Catalysts prepared from treated supports showed the best catalytic performance in ethanol combustion. At high manganese loading, this better catalytic performance was related to the high capacity for adsorbing oxygen. While at low manganese loading, the great amount of dispersed surface manganese oxide species and/or the existence of surface defects were relevant in the catalytic activity. On the other hand, the reactivity of the catalysts in toluene combustion was roughly correlated with the reducibility of the surface manganese oxide species. On the basis of these observations, we conclude that the ethanol combustion occurs by a suprafacial mechanism whereas the toluene combustion proceeds through an intrafacial mechanism. of the support treatment on the catalytic behavior in ethanol and toluene combustion was studied. The treatments modified the alumina physicochemical properties (porosity, surface area, isoelectric point, and surface acidity). The modification of these properties affected the interaction of the manganese oxide species with the support and increased the dispersion of the active phase. Catalysts prepared from treated supports showed the best catalytic performance in ethanol combustion. At high manganese loading, this better catalytic performance was related to the high capacity for adsorbing oxygen. While at low manganese loading, the great amount of dispersed surface manganese oxide species and/or the existence of surface defects were relevant in the catalytic activity. On the other hand, the reactivity of the catalysts in toluene combustion was roughly correlated with the reducibility of the surface manganese oxide species. On the basis of these observations, we conclude that the ethanol combustion occurs by a suprafacial mechanism whereas the toluene combustion proceeds through an intrafacial mechanism. x/ Al2O3 catalysts with two different loadings. The influence of the support treatment on the catalytic behavior in ethanol and toluene combustion was studied. The treatments modified the alumina physicochemical properties (porosity, surface area, isoelectric point, and surface acidity). The modification of these properties affected the interaction of the manganese oxide species with the support and increased the dispersion of the active phase. Catalysts prepared from treated supports showed the best catalytic performance in ethanol combustion. At high manganese loading, this better catalytic performance was related to the high capacity for adsorbing oxygen. While at low manganese loading, the great amount of dispersed surface manganese oxide species and/or the existence of surface defects were relevant in the catalytic activity. On the other hand, the reactivity of the catalysts in toluene combustion was roughly correlated with the reducibility of the surface manganese oxide species. On the basis of these observations, we conclude that the ethanol combustion occurs by a suprafacial mechanism whereas the toluene combustion proceeds through an intrafacial mechanism. of the support treatment on the catalytic behavior in ethanol and toluene combustion was studied. The treatments modified the alumina physicochemical properties (porosity, surface area, isoelectric point, and surface acidity). The modification of these properties affected the interaction of the manganese oxide species with the support and increased the dispersion of the active phase. Catalysts prepared from treated supports showed the best catalytic performance in ethanol combustion. At high manganese loading, this better catalytic performance was related to the high capacity for adsorbing oxygen. While at low manganese loading, the great amount of dispersed surface manganese oxide species and/or the existence of surface defects were relevant in the catalytic activity. On the other hand, the reactivity of the catalysts in toluene combustion was roughly correlated with the reducibility of the surface manganese oxide species. On the basis of these observations, we conclude that the ethanol combustion occurs by a suprafacial mechanism whereas the toluene combustion proceeds through an intrafacial mechanism. 2O3 catalysts with two different loadings. The influence of the support treatment on the catalytic behavior in ethanol and toluene combustion was studied. The treatments modified the alumina physicochemical properties (porosity, surface area, isoelectric point, and surface acidity). The modification of these properties affected the interaction of the manganese oxide species with the support and increased the dispersion of the active phase. Catalysts prepared from treated supports showed the best catalytic performance in ethanol combustion. At high manganese loading, this better catalytic performance was related to the high capacity for adsorbing oxygen. While at low manganese loading, the great amount of dispersed surface manganese oxide species and/or the existence of surface defects were relevant in the catalytic activity. On the other hand, the reactivity of the catalysts in toluene combustion was roughly correlated with the reducibility of the surface manganese oxide species. On the basis of these observations, we conclude that the ethanol combustion occurs by a suprafacial mechanism whereas the toluene combustion proceeds through an intrafacial mechanism.