CATALYTIC CRACKING CATALYST OF RARE EARTH-CONTAINING Y-TYPE MOLECULAR SIEVE AND PREPARATION METHOD THEREFOR

摘要

The present invention relates to a catalytic cracking catalyst and a preparation method therefor; the catalytic cracking catalyst contains an active cracking component, an optional mesoporous silicon-aluminium material, clay and a bonder, wherein the cracking active component substantially comprises or consists of the group of a rare earth-containing Y-type molecular sieve, optional other Y-type molecular sieves and optional molecular sieves having an MET structure; for the rare earth-containing Y-type molecular sieve, the rare earth content thereof based on the rare earth oxide is 10 wt%- 25 wt%, such as 11 wt%-23 wt%, the lattice constant is 2.440 nm-2.472 nm, such as 2.450 nm-2.470 nm, the degree of crystallinity is 35%-65%, such as 40%-60%, and the atomic ratio of the skeleton silicon/aluminium is 2.5-5.0. The product of the ratio of the intensity I1 of the peak 2&thetas; = 11.8° ± 0.1° to the intensity I2 of the peak 2&thetas; = 12.3° ± 0.1° in the X-ray diffraction pattern of the molecular sieve multiplied by the rare earth percentage by weight based on the rare earth oxide is greater than 48, and preferably greater than 55.