Patent · US Expired

Removal of nitrogen oxides from gases

US5955045A · kind A · utility

6Cited by
2References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 13, 1997
Grant dateSep 21, 1999
Priority date
Expiry dateJun 13, 2017

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC10G70/046
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

For selectively removing nitrogen oxides from a carrier gas that contains hydrocarbons, the nitrogen oxides are removed by chemisorption on metal oxides, without the occurrence of undesirable secondary reactions. The metal oxides are preferably formed from metals of the 6th to 8th subgroups, whereby manganese dioxide (MnO.sub.2,) is especially preferred as a metal oxide. The process can be conducted with one or more reactor beds, which preferably operate at 10 to 40.degree. C. and are regenerated with nitrogen at a temperature of 130 to 170.degree. C. By removing nitrogen oxides from an olefin-rich gas, for example from the waste gas of an FCC unit, the resultant gas can then be fed to a cryogenic olefin extraction stage without danger of explosion. Such a waste gas contains unsaturated hydrocarbons, hydrogen, carbon monoxide, and oxygen, the oxygen having a concentration preferably between 100 and 5000 mol ppm.

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