Production of faujasites with high-silica skeleton

The process of production of faujasite with a high silica (HS) skeleton by water steam high-temperature treatment (600-800° C, 101 kPa) of zeolites with Si-Al ratio in the lattice being 2.4-3 was studied by the methods of IR-spectroscopy, magic angle rotation NMR, X-ray phase analysis and pulsed microcatalytic method. Thoroughly substituted ammonium forms of zeolites and amorphous alumosilicates, as well as NH4NaY and NH4LaY zeolites of different degree of decationization were used as initial components. It is shown that chemical composition affects considerably the depth of zeolite lattice dealuminization, dynamics of aluminium removal from the skeleton, quality and number of acid centres, type and properties of non-lattice aluminium compounds and catalytic activity in cracking processes.