Process for reducing NO.sub.x from exhaust fumes

US6153161A · kind A · utility

Assignee

• BASF SE

Inventors

• Thomas Fetzer · Speyer, DE
• Bernd Morsbach · Ludwigshafen, DE
• Martin Hartweg · Erbach, DE
• Ralf-Dirc Roitzheim · Blaustein, DE
• Andrea Seibold · Blaustein, DE
• Leonhard Walz · Rastatt, DE

Key dates

• Filing date: Jun 2, 1998
• Grant date: Nov 28, 2000
• Expiry date: Jun 2, 2018

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S502/524
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

NO.sub.x, where x is 1 and 2, in exhaust gases is reduced over heterogeneous catalysts with hydrocarbons, carbon monoxide, hydrogen or mixtures thereof in the presence of oxygen from 100 to 650.degree. C. and an absolute pressure of from 0.5 to 50 bar by a process in which the heterogeneous catalysts used are bimodal or polymodal compounds of the general formula I EQU A.sub.1-x M.sub.2 O.sub.4 (I), which, if required, are doped with rare earth metals, noble metal, titanium, vanadium, molybdenum, tungsten or mixtures thereof, and where PA1 A is magnesium, calcium, titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc, tin or mixtures thereof, PA1 M is aluminum, gallium, indium, tin, chromium, manganese, iron, cobalt, nickel, copper, zinc or mixtures thereof and PA1 x is from 0 to 0.99, whose oxygen atoms are in a cubic close packed arrangement and A is present in the tetrahedral sites and M in the octahedral sites, it also being possible for A to occupy octahedral sites if an equivalent amount of M occupies tetrahedral sites.