Methods to improve heteroatom lattice substitution in large and extra-large pore borosilicate zeolites
US6790433B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 18, 2002 |
| Grant date | Sep 14, 2004 |
| Priority date | — |
| Expiry date | Oct 18, 2022 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01B39/026
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
The invention, in one embodiment, is a method for preparing crystalline zeolites by (a) contacting a calcined essentially aluminum free borosilicate zeolite with an aqueous acid solution, thereby producing an at least partially deboronated zeolite; (b) contacting said at least partially deboronated zeolite with a solution selected from the group consisting of an aqueous aluminum salt solution, thereby producing an aluminosilicate zeolite; an aqueous gallium salt solution, thereby producing a gallosilicate zeolite; an aqueous iron salt solution, thereby producing a ferrosilicate zeolite; and mixtures thereof; and (c) where the contacting in step (b) occurs at a pH of not greater than about 3.5. In another embodiment, the present invention provides a method for preparing crystalline zeolites by contacting a calcined essentially aluminum free large or extra-large pore borosilicate zeolite with a solution selected from the group consisting of an aqueous aluminum salt solution, thereby producing an aluminosilicate zeolite; an aqueous gallium salt solution, thereby producing a gallosilicate zeolite; an aqueous iron salt solution, thereby producing a ferrosilicate zeolite; and mixtures th…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.