Exhaust system with a modified lean NOx trap
US9828896B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 7, 2015 |
| Grant date | Nov 28, 2017 |
| Priority date | — |
| Expiry date | Feb 1, 2036 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/12
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
An exhaust system for treating an exhaust gas from an internal combustion engine is disclosed. The system comprises a modified lean NOx trap (LNT), a urea injection system, and an ammonia-selective catalytic reduction catalyst. The modified LNT comprises a first layer and a second layer. The first layer comprises a NOx adsorbent component and one or more platinum group metals. The second layer comprises a diesel oxidation catalyst zone and an NO oxidation zone. The diesel oxidation catalyst zone comprises a platinum group metal, a zeolite, and optionally an alkaline earth metal. The NO oxidation zone comprises a platinum group metal and a carrier. The modified LNT stores NOx at temperatures below about 200° C. and releases at temperatures above about 200° C. The modified LNT and a method of using the modified LNT are also disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.