The influence of adariantane on the reaction of n-heptane over H-Y, H-β and H-mordenite zeolites

The effect of adamantane (Ad) on the activity and selectivity of acidic zeolites Y, β and mordenite (M) in the isomerization and cracking of n-heptane (C₇) in He at 443 K was studied. Ad was found to promote the isomerization of C₇. The Ad uptake of the zeolites, and the IR spectra obtained from the zeolite-bound Ad were determined. It was found that Ad did not remain completely unconverted under the conditions of the C₇ reaction. The activity of the catalysts in the conversion of Ad increased in the sequence of H-Y < H-β < H-M. Existing data suggest that a fraction of the Ad, responsible for the cocatalytic effect, can participate in hydride transfer processes and remain unconverted, while another fraction, depending on catalyst acidity, is converted to dimer and oligomers.