Die Protonenresonanz von adsorbiertem Benzol an Zeolithen des Faujasittyps mit verschiedenen Si/Al-Verhältnissen / The Proton Resonance of Adsorbed Benzene in Zeolites of the Faujasite Type with Different Si/Al-ratioes

Abstract

At high Si/Al-ratioes of faujasite type zeolites, the cations in S2-position at the walls of the large cages are the prefered centers of sorption. In the present paper, the shape of the resonance lines is studied for samples with Si/Alratioes high enough so that different numbers of these ions can be expected. For samples with Si/Al above 2.43, a narrow line can be observed at high coverages, superimposing the broad line and indicating benzene molecules with a higher mobility, the intensity of which increases with increasing Si/Al-ratio or decreasing number of S2-ions in the large cage. The possible importance of this observation for the catalytic activity of these substances is shortly discussed in connection with results of other authors