Low-temperature NOx storage catalyst used for automobile exhaust purification and preparation method thereof
US11612859B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 12, 2020 |
| Grant date | Mar 28, 2023 |
| Priority date | — |
| Expiry date | Jun 13, 2040 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/12
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A low-temperature NOx storage catalyst for automobile exhaust purification and a preparation method thereof. Loading a noble metal salt solution on molecular sieve by equal volume impregnation method, wherein the noble metal salt solution comprises palladium nitrate and platinum nitrate, and the molecular sieve comprises SSZ, SAPO and BETA, then drying at 60-120° C. for 2-6 h, roasting at 500-550° C. in air for 2-5 h, and further roasting at 750-850° C. in air for 2-5 h, and then mixing with aluminum sol, ball milling and pulping, and then coating the slurry on a carrier, wherein the loading on the coating is 100-250 g/L and the noble metal content is 10-150 g/ft3, drying at 60-120° C. for 2-6 h, then roasting at 500-550° C. in air for 2-5 h, and further continuing roasting at 750-850° C. in air for 2-5 h, to obtain the catalyst. Loading the noble metals Pt and Pd into a pore channel of a molecular sieve improves NOx storage capacity of a catalyst at low temperatures, and selecting a different type of molecular sieve as an NOx storage unit and increasing a roasting temperature of a molecular sieve material on which Pt and Pd are loaded significantly increases NOx storage capacity.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.