Thermographic and Mass Spectrometric Study on Zeolite Dehydration and Deammoniation

Thermography and thermal desorption with mass spectrometric monitoring have been applied to dehydration, deammoniation, and dehydroxylation in cationic, NH4, H, and dealuminated forms of synthetic zeolites of faujasite and mordenite types, as well as natural mordenite. The dehydration temperatures for the synthetic materials are only slightly dependent on the cation form. As the window size decreases and the Si/Al ratio in the framework increases, the deammoniation and dehydroxylation temperatures rise in the sequence Y < M < Mh.