Process for the reduction of the nitrogen oxides in exhaust gases using a zeolite-containing catalyst

US4946659A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Wolfgang Held · Emmendingen, DE
• Axel Konig · Wemmel, BE
• Lothar Puppe · Burscheid, DE

Key dates

• Filing date: Aug 21, 1989
• Grant date: Aug 7, 1990
• Expiry date: Aug 21, 2009

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02T10/12
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

An improvement in the removal of nitrogen oxides from the exhaust gases of internal combustion engines is achieved by adding urea or a urea-containing reducing agent to the exhaust gases and contacting the gases under oxidizing conditions with a zeolite containing catalyst.