SCR catalysts having improved low temperature performance, and methods of making and using the same
US11000836B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 24, 2019 |
| Grant date | May 11, 2021 |
| Priority date | — |
| Expiry date | Apr 24, 2039 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/12
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
SCR-active molecular-sieve based catalysts with improved low-temperature performance are made by heating a molecular-sieve in a non-oxidizing atmosphere with steam (hydrothermal treatment), or in a reducing atmosphere without steam (thermal treatment), at a temperature in the range of 600-900° C. for a time period from 5 minutes to two hours. The resulting SCR-active iron-containing molecular sieves exhibit a selective catalytic reduction of nitrogen oxides with NH3 or urea at 250° C. that is at least 50% greater than if the iron-containing molecular-sieve were calcined at 500° C. for two hours without performing the hydrothermal or thermal treatment.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.