Propiedades ácidas de mordenitas modificadas por desaluminización
Resumen
Se estudia la desaluminización de la mordenita tratada hidro térmicamente. El aluminio extra-red ALER producido durante la desaluminización se encuentra bajo diferentes formas, una iónica en posición de intercambio, una neutra y y una fase amorfa invisible al RMN del 27Al. Los sitios ácidos de Lewis observados son asociados con la presencia de especies ALER en los canales de la mordenita. No se distingue una dependencia directa entre la fuerza de los sitios ácidos de Bronsted y el contenido en aluminio reticular ALR. Sin embargo, el número de los sitios ácidos titulados por la piridina aumenta luego de la desaluminización. los estudios de adsorción muestran la aparición de una red mesoporosa secundaria, la cual disminuye las restricciones difusionales al interior del grano.
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