TEMPERATURE-PROGRAMMED DESORPTION OF AMMONIA FROM NA- AND H-Y ZEOLITES - DESORPTION ENERGIES DERIVED FROM ANALYSES OF TPD PROFILES BY 2 NEW METHODS

The thermal gravimetric desorption profiles of NH3 from the Na- and H-forms of zeolite Y and some dealuminated samples have been analyzed by (i) single heating rate, and (ii) variable heating rate methods. The activation energies and entropies of desorption obtained by the two methods have been compared. Both methods have been shown to give accurate, sensible energies of desorption and, thus, both methods could be used to characterize the acidity of zeolite acid catalysts. © 1990.