Rare earth stabilized Cr/Ti substituted molecular sieves
US5688975A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 10, 1996 |
| Grant date | Nov 18, 1997 |
| Priority date | — |
| Expiry date | Apr 10, 2016 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01B39/06
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Molecular sieve compositions have been synthesized which are resistant to the loss of framework atoms. Specifically, the molecular sieves of the invention have the empirical formula EQU mA: (M.sub.w Al.sub.x Si.sub.y)O.sub.2 where A is at least one rare earth metal, M is chromium or titanium and "m", "w", "x" and "y" are the mole fractions of A, M, Al and Si respectively. Applicants have discovered that the rare earth metals prevent loss of chromium and titanium from the framework and degradation of the molecular sieve. Along with the composition, a process for preparing the composition and processes using the composition are disclosed and claimed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.