CATALYTIC ACTIVITY AND ACID PROPERTIES OF Al-PENTASILS AND ISOMORPHICALLY SUBSTITUTED (Fe, B) SILICATES

Article abstract of DOI:10.1007/BF00960641

The catalytic activity of Al-containing pentasils and their isomorphically substituted analogs (ferri- and borosilicates) in transformations of n-alkanes are directly dependent on their acidity.Elemental silicates have a lower acidity and are significantly less active in cracking and aromatization of n-alkanes of C6-C10 composition than Al-pentasils.The gegree of conversion of alkanes decreases and the aromatizing capacity of zeolites decreases strongly with a decrease in the concentration of acid sites on pentasils with a different composition of the framework (SiO2/Al2O3 35-1000).Ferri- and borosilicates are close in activity in cracking and aromatization of n-alkanes but differ significantly in their acid characteristics.In particular, NH3 is adsorbed on ferrisilicate with high heats both an acid sites active in these reactions and in the Fe2O3 phase present in the ferrisilicate and inactive in catalysis.