INCAPE   05401
INSTITUTO DE INVESTIGACIONES EN CATALISIS Y PETROQUIMICA "ING. JOSE MIGUEL PARERA"
Unidad Ejecutora - UE
artículos
Título:
Characterization of ZnAl2O4 Obtained by Different Methods
Autor/es:
ADRIANA D. BALLARINI; SONIA A. BOCANEGRA; ALBERTO A. CASTRO; SERGIO R. DE MIGUEL; OSVALDO A. SCELZA
Revista:
CATALYSIS LETTERS
Editorial:
Springer
Referencias:
Lugar: Heidelberg, Alemania; Año: 2008
ISSN:
1011-372X
Resumen:
In this work the synthesis of a ZnAl2O4 spinel
to be used as a support of metals and its characterization
were studied. The methods used for the ZnAl2O4 preparation
were: ceramic method (CM), mechanochemical
synthesis in humid medium (HMS) and coprecipitation
(COPR). ZnAl2O4 CM and ZnAl2O4 HMS showed negligible
acidity, but the ZnAl2O4 COPR displayed a low
acidity. The spinels obtained by COPR and HMS showed
higher specific surface area and pore volumes than that
prepared by the ceramic method. In addition the catalytic
performance of Pt supported on the prepared spinel was
evaluated in the n-butane dehydrogenation reaction. The Pt
catalysts prepared with ZnAl2O4 COPR presented better
activity and selectivity to olefins than the ones prepared
with ZnAl2O4 HMS and ZnAl2O4 CM, which could be
correlated with a higher metallic dispersion and lower
particle sizes, detected by TEM. The acidity of ZnAl2O42O4 spinel
to be used as a support of metals and its characterization
were studied. The methods used for the ZnAl2O4 preparation
were: ceramic method (CM), mechanochemical
synthesis in humid medium (HMS) and coprecipitation
(COPR). ZnAl2O4 CM and ZnAl2O4 HMS showed negligible
acidity, but the ZnAl2O4 COPR displayed a low
acidity. The spinels obtained by COPR and HMS showed
higher specific surface area and pore volumes than that
prepared by the ceramic method. In addition the catalytic
performance of Pt supported on the prepared spinel was
evaluated in the n-butane dehydrogenation reaction. The Pt
catalysts prepared with ZnAl2O4 COPR presented better
activity and selectivity to olefins than the ones prepared
with ZnAl2O4 HMS and ZnAl2O4 CM, which could be
correlated with a higher metallic dispersion and lower
particle sizes, detected by TEM. The acidity of ZnAl2O42O4 preparation
were: ceramic method (CM), mechanochemical
synthesis in humid medium (HMS) and coprecipitation
(COPR). ZnAl2O4 CM and ZnAl2O4 HMS showed negligible
acidity, but the ZnAl2O4 COPR displayed a low
acidity. The spinels obtained by COPR and HMS showed
higher specific surface area and pore volumes than that
prepared by the ceramic method. In addition the catalytic
performance of Pt supported on the prepared spinel was
evaluated in the n-butane dehydrogenation reaction. The Pt
catalysts prepared with ZnAl2O4 COPR presented better
activity and selectivity to olefins than the ones prepared
with ZnAl2O4 HMS and ZnAl2O4 CM, which could be
correlated with a higher metallic dispersion and lower
particle sizes, detected by TEM. The acidity of ZnAl2O42O4 CM and ZnAl2O4 HMS showed negligible
acidity, but the ZnAl2O4 COPR displayed a low
acidity. The spinels obtained by COPR and HMS showed
higher specific surface area and pore volumes than that
prepared by the ceramic method. In addition the catalytic
performance of Pt supported on the prepared spinel was
evaluated in the n-butane dehydrogenation reaction. The Pt
catalysts prepared with ZnAl2O4 COPR presented better
activity and selectivity to olefins than the ones prepared
with ZnAl2O4 HMS and ZnAl2O4 CM, which could be
correlated with a higher metallic dispersion and lower
particle sizes, detected by TEM. The acidity of ZnAl2O42O4 COPR displayed a low
acidity. The spinels obtained by COPR and HMS showed
higher specific surface area and pore volumes than that
prepared by the ceramic method. In addition the catalytic
performance of Pt supported on the prepared spinel was
evaluated in the n-butane dehydrogenation reaction. The Pt
catalysts prepared with ZnAl2O4 COPR presented better
activity and selectivity to olefins than the ones prepared
with ZnAl2O4 HMS and ZnAl2O4 CM, which could be
correlated with a higher metallic dispersion and lower
particle sizes, detected by TEM. The acidity of ZnAl2O4n-butane dehydrogenation reaction. The Pt
catalysts prepared with ZnAl2O4 COPR presented better
activity and selectivity to olefins than the ones prepared
with ZnAl2O4 HMS and ZnAl2O4 CM, which could be
correlated with a higher metallic dispersion and lower
particle sizes, detected by TEM. The acidity of ZnAl2O42O4 COPR presented better
activity and selectivity to olefins than the ones prepared
with ZnAl2O4 HMS and ZnAl2O4 CM, which could be
correlated with a higher metallic dispersion and lower
particle sizes, detected by TEM. The acidity of ZnAl2O42O4 HMS and ZnAl2O4 CM, which could be
correlated with a higher metallic dispersion and lower
particle sizes, detected by TEM. The acidity of ZnAl2O42O4
COPR, observed by isopropanol dehydration and TPD of
pyridine, and the sequence of specific surface areas of the
different spinels (ZnAl2O4 COPR[ZnAl2O4 HMS[2O4 COPR[ZnAl2O4 HMS[
ZnAl2O4 CM) are other important factors to define the final
dispersion of the catalysts.2O4 CM) are other important factors to define the final
dispersion of the catalysts.