Microwave synthesis of iron oxide catalysts for cold start NOx removal
US11471873B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 24, 2019 |
| Grant date | Oct 18, 2022 |
| Priority date | — |
| Expiry date | Nov 13, 2040 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/12
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
Methods of making an iron based catalyst using microwave hydrothermal synthesis are provided. The methods include dissolving iron(III) nitrate, Fe(NO3)3, in an organic solvent to form a solution. Once dissolved, the methods include a step of neutralizing the solution with an alkaline mineralizing agent to obtain a precipitate. The solution with the precipitate is then subjected to microwave radiation to cause a temperature gradient and a hydrothermal crystallization process to form a synthesized product. The synthesized product is subsequently separated from the mineralizing agent. The method includes washing and drying the synthesized product to obtain particles of sodium iron oxide (NaFeO2) catalyst that can be used as a composition for a passive NOx adsorber. A two-stage NOx abatement device for removal of NOx from an exhaust gas stream during a cold start operation of an internal combustion engine is also provided.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.