Composite oxide, process for producing the same, catalyst for purifying exhaust gas, and process for producing the same
US6852665B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 25, 2001 |
| Grant date | Feb 8, 2005 |
| Priority date | — |
| Expiry date | Mar 26, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/12
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A composite oxide includes agglomerated particles which have an average particle diameter of 20 μm or less, which are composed of a plurality of metallic element oxides being in form of fine particles having an average diameter of 50 nm or less, and which have a surface and an inner portion whose metallic element distributions differ with each other. The characteristics of the respective metallic elements are exhibited maximally. Hence, it is extremely useful as a support for an exhaust gas purifying catalyst. The catalyst exhibits the activities which degrade less even after it is subjected to a sever durability, is good in terms of the heat and sulfur-poisoning resistance, and can efficiently purify the harmful components in exhaust gases. Moreover, it is possible to produce such a composite oxide and catalyst easily and stably by production processes disclosed herein.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.