Catalysts for reducing nitrogen oxides to molecular nitrogen in a superstoichiometric medium of oxidizing compounds, process for preparation, and uses
US5736482A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 5, 1996 |
| Grant date | Apr 7, 1998 |
| Priority date | — |
| Expiry date | Feb 5, 2016 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02C20/10
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
Described is catalyst that is active and selective for reducing to molecular nitrous oxides contained in a superstoichiometric medium of oxidizing agents, said reduction being conducted with agents such as carbon monoxide, hydrogen, hydrocarbons, alcohols, ethers, and other oxidized organic compounds and also with ordinary fuels such as gasolines, gas oils, liquefied gases, and compressed natural gases, whereby said catalyst comprises: PA1 at least one refractory inorganic oxide, including alumina; PA1 at least one element (A) that belongs to the group of rare earths; PA1 at least one element (B) that belongs to groups VIB, VIIB, VIII and IB of transition metals; PA1 at least one metal (C) that belongs to the group of precious metals of the platinum family, and optionally PA1 at least one element (D) that belongs to group IIA of alkaline-earths; PA1 at least a portion of elements (A) is combined with alumina to form at the surface of the latter a microlayer of rare-earth aluminate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.