Patent · US Expired

Process for eliminating oxides of nitrogen

US6551564B1 · kind B1 · utility

6Cited by
9References
24Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 8, 2000
Grant dateApr 22, 2003
Priority date
Expiry dateDec 6, 2020

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB01D2258/012
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

The invention concerns materials for eliminating oxides of nitrogen NO and NO2 present in exhaust gases, in particular from the internal combustion engines of automotive vehicles operating in a medium which is super-stoichiometric in oxidising agents, which can adsorb oxides of nitrogen then desorb the oxides of nitrogen by elevating the temperature with respect to the adsorption temperature or by passage of rich mixture, said materials comprising mixed oxides the metals of which are in octahedral coordination, with the octahedra connecting together so that the structure generates micropores in the form of channels. These materials adsorb oxides of nitrogen by insertion and do not become poisoned in contact with oxides of sulphur and carbon contained in the gases. In the presence of a group VIII metal, these materials are capable of eliminating oxides of nitrogen absorded by reduction during passage of a rich mixture.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.