Target modification of acid properties of ultrastable zeolite Y: 2. Effectof treatment with phosphorus and boron compounds on activity in isomerization of n-hexane

The catalytic properties of ultrastable zeolites Y modified with phosphorus and boron compounds, as well as of 0.5 wt % platinum-loaded catalyst speci mens prepared from these zeolites were examined in the n-hexane isomerizati on reaction. Information on the structure of the Pt-containing catalysts wa s obtained by IR and XPS techniques, and the number and strength distributi on of acid sites were determined by fitting calculated data to the experime ntal data on temperature-programmed ammonia desorption. The comparison of t he data on n-hexane conversion and selectivity for conversion products with the structure and acidity characteristics of the specimens allowed a concl usion on the nature of their catalytic activity to be drawn.