THE ASSESSMENT OF BRONSTED ACIDITY CONCENTRATION IN HY ZEOLITES BY PROPAN-2-OL DEHYDRATION AND OTHER METHODS

Dehydration of propan-2-ol was studied on a series of HY zeolites with nominal proton contents up to 20 per unit cell. The combined rates of propene and diisopropyl ether formation at 370 K, when considered in conjunction with the effects of pyridine poisoning, showed most Bronsted acid sites to be equivalent, possessing a turnover number in terms of products of 5.1 X 10(-4) s-1. Bronsted acid site concentrations so determined compare favorably with those from infrared spectroscopy of adsorbed pyridine and temperature-programmed desorption of ammonia.