ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Structure properties of dealuminated Y-zeolites

V. Patzelová, A. Zukal, and J. Kloubek

J. Heyrovský Institute of Physical Chemistry and Electrochemistry, Czechoslovak Academy of Sciences, CS-121 38 Pragu

Abstract: The structure of a modified zeolite of the type Y was investigated, which has been prepared by hydrothermal modification of the sodium-ammonium form NaNFLY followed by the extraction of those aluminium atoms which have been removed from their positions in the lattice in the course of the modifica- tion. The results of the measurement of both adsorption isotherms of benzene and mercury porosimetry performed on the structure modified in this way were correlated with the values obtained by measurements carried out with the original NaY form. The following conclusions were drawn: 1. In the course of the hydrothermal treatment of the zeolite a decrease in the volume of the micropores takes place which is due to the decay of a part of the elementary structure units — the cubooctahedra — and the resulting formation of secondary mesopores. 2. The silicium atoms liberated in this way cause an annealing of the lattice defects originating from the hydrolytical removal of a part of aluminium atoms, i.e. they fill the vacancies in the unperturbed part of the structure.

Full paper in Portable Document Format: 393a361.pdf

Chemical Papers 39 (3) 361–367 (1985)