Exhaust gas-purifying composition
US10434502B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 26, 2017 |
| Grant date | Oct 8, 2019 |
| Priority date | — |
| Expiry date | Jul 26, 2037 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF01N2510/063
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
The present invention provides an exhaust gas purifying composition containing BEA zeolite containing phosphorus, wherein an amount of phosphorus is such that a molar ratio thereof with respect to Al in the zeolite is 0.5 or greater, and a maintaining factor RS of a specific surface area of the exhaust gas purifying composition after heating at 980° C. for 25 hours is 35% or greater. Furthermore, the present invention also provides an exhaust gas purifying composition containing phosphorus-containing zeolite, wherein an amount of phosphorus is such that a molar ratio thereof with respect to Al in the zeolite is from 0.5 to 8, and a maintaining factor Rd of a crystallite diameter after heating at 980° C. for 25 hours is 50% or greater. The exhaust gas purifying composition of the present invention has excellent HC purifiability for exhaust gas purification in internal combustion engines such as gasoline engines.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.