THE EFFECT OF EXCHANGE DEGREE ON THE HETEROGENEITY OF ACID SITES IN DECATIONATED MORDENITES

Adsorption microcalorimetry, TPD, and IR spectroscopy indicate a nearl y linear relationship between the number of acid sites and die decatio nization level of mordenites. Growth of the exchange level increases t he acid strength, and removal of the last NH4+ ions results in sites w ith q(NH3) = 130 - 160 kJ/mol. Mordenites are more active in the crack ing of n-octane than HY zeolites are, and this was related to an incre ased concentration of the strong acid sites. With bulkier reactants, s uch as iso-octane and ethylbenzene, the difference in catalytic activi ty decreases.