Alumina-based nitrogen oxide (NOx) trapping compositions and treatment of vehicular exhaust gases therewith
US9216381B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 7, 2007 |
| Grant date | Dec 22, 2015 |
| Priority date | — |
| Expiry date | Oct 30, 2030 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01J2523/00
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
Thermally stable, solid alumina-based compositions useful for the trapping of nitrogen oxides that are contained in gaseous fluids, notably in vehicular exhaust gases, are formed of alumina, cerium and a divalent metal M selected from among barium, strontium or an association of these two elements and which include at least 10% of the weight of element M expressed by weight of oxide in contrast to the total weight of the composition and also wherein the aluminate compound of the metal element M, i.e., MAl2O4, is absent and not detectable by X-ray diffraction of the composition, after calcination thereof with air at 700° C. for two hours.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.