Patent · US Expired

Method and apparatus for treating an engine exhaust gas stream

US6171556A · kind A · utility

152Cited by
41References
25Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 19, 1993
Grant dateJan 9, 2001
Priority date
Expiry dateNov 19, 2013

Classification

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

Abstract

A method and apparatus in accordance with the invention is described which comprises treating an engine exhaust gas stream containing hydrocarbons and other pollutants. The method of this invention comprises the steps of flowing the exhaust gas stream through a catalytic member comprising a monolith body having a first catalyst zone and a second catalyst zone therein to contact a catalyst in a first catalyst zone to convert at least some of the pollutants in the exhaust gas stream into innocuous products. The exhaust gas stream is then discharged from the catalytic member and flowed through an adsorbent zone to adsorb at least some of the hydrocarbon pollutants with an adsorbent composition. The exhaust gas stream is then discharged from the adsorbent zone and flowed to the second catalyst zone to convert at least some of the pollutants into innocuous products. The exhaust gas stream, so treated, is then discharged to the atmosphere through suitable discharge means. A preferred adsorbent is a zeolite, having a relatively high silica to alumina ratio and a low relative Bronsted acidity. The preferred adsorbent compositions comprise Beta zeolites. An oxidant such as air may be added …

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