Composition based on cerium oxide and on zirconium oxide having a high reducibility and high specific surface, methods for the preparation thereof and use as a catalyst
US7939040B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 2, 2004 |
| Grant date | May 10, 2011 |
| Priority date | — |
| Expiry date | Sep 3, 2025 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01P2006/12
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
The inventive composition is based on cerium oxide and on zirconium oxide in an atomic proportion Ce/Zr of at least 1, and has a reducibility rate of at least 70% and a surface area of at least 15 m; 2; /g. This composition is obtained by a method in which: a mixture is made containing cerium and zirconium compounds; this mixture is provided with a basic compound whereby obtaining a precipitate that is heated in an aqueous medium; a surfactant-type additive or a polyethylene glycol or a carboxylic acid is added to this medium or to the separated precipitate; the mixture is ground; the precipitate obtained thereof is calcined under inert gas or vacuum, in a first period of time, at a temperature of at least 850° C. and then under an oxidizing atmosphere, in a second period of time, at a temperature of at least 400° C.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.