Several features of the dealumination of type Y zeolite using silicon tetrachloride and ethylenediaminetetraacetic acid

Dealumination of type Y zeolite using SiCl₄ produces a statistically averaged distribution of Al and Si atoms in the framework. The action of H₄EDTA causes defects in the backbone and partial amorphization of the zeolite. Extracellular particles containing Al form due to dealumination with SiCl₄. The maximum number of these occurs at n_al ^bb=5–16 atoms/unit cell. Treatment with H₄EDTA has practically no effect on the composition of the particles, which are largely sodium cations. The extracellular particles localize both in sodalite cells and in large voids after dealumination with SiCl₄.The authors thank V. M. Mastikhin for recording the²⁷A1 and²⁹Si NMR spectra and S. A. Dubkova for taking the low-temperature x-ray diffraction spectra and calculating the _e map.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 967–973, May, 1990.