Aggregates of small crystallites of zeolite Y

摘要

This invention relates to aggregates of small primary crystallites of zeolite Y that are clustered into larger secondary particles. At least 80% of the secondary particles may comprise at least 5 primary crystallites. The size of the primary crystallites may be at most about 0.5 micron, or at most about 0.3 micron, and the size of the secondary particles may be at least about 0.8 micron, or at least about 1.0 μm. The silica to alumina ratio of the resulting stabilized aggregated Y zeolite may be 4:1 or more.

主权项

1. A highly aggregated form of zeolite Y comprising small size primary crystallites of zeolite Y, wherein at least 80% of the primary crystallites are aggregated to form secondary particles having an external surface, wherein the zeolite exhibits a silica to alumina molar ratio of 4:1 or more, wherein an average size of the secondary particles, as viewed from the external surface of the secondary particles, is about 0.8 micron or more, and wherein at least one of the following conditions apply:
(a) an average size of the primary crystallites in the secondary particles, as viewed from the external surface of the secondary particles, is about 0.5 micron or less; (b) at least 80% of the secondary particles comprise at least 5 primary crystallites; and (c) in at least 80% of the secondary particles, a ratio of the average size of the secondary particles to the average size of the primary crystallites is at least 3:1.