Patent · US Expired

Method of purifying oxygen-excess exhaust gas

US5433933A · kind A · utility

22Cited by
14References
6Claims
0Family size

Assignees

Inventors

Key dates

Filing dateDec 30, 1993
Grant dateJul 18, 1995
Priority date
Expiry dateDec 30, 2013

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02T10/12
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

A method for purifying an exhaust gas containing an excess amount of oxygen, to remove nitrogen oxides, carbon monoxide and hydrocarbons therefrom, by bringing a catalyst into contact with the exhaust gas, the catalyst comprising a zeolite ion-exchanged with (a) cobalt or (b) both cobalt and at least one metal selected from the group consisting of alkaline earth metals and rare earth metals, the zeolite being selected from the group consisting of ferrierite, ZSM-5, ZSM-11, ZSM-12 and ZSM-20, and having a silica-to-alumina molar ratio of from 15 to 1,000.

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