Process for the manufacture of catalytic elements and catalytic elements so produced

US4895821A · kind A · utility

Assignees

• Didier-Werke AG · DE
• Didier Engineering GmbH · DE

Inventors

• Hartmut Kainer · Wiesbaden, DE
• Eugen Buhler · Thannhausen, DE
• Daniel Grimm · Schlangenbad, DE
• Wilfried Schenelle · Wiesbaden, DE
• Claus Flockenhaus · Essen, DE
• Karl H. Laue
• Klaus Merkel · Essen, DE

Key dates

• Filing date: Aug 12, 1988
• Grant date: Jan 23, 1990
• Expiry date: Aug 12, 2008

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B01J23/862
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

This invention relates to a process for the manufacture of catalysts for the reduction of nitrogen oxides in exhaust gases or for chemical air cleaning processes, in which catalyst moldings are produced from iron oxide or mixtures of iron oxide and chromium oxide and/or manganese oxide, which are reduced to grain sizes less than 2 mm, with the use of inorganic binders and sulfuric acid, and with the possible addition of activating additives. In accordance with the invention: PA1 (a) either the mixture of the solid primary material is reacted with sulfuric acid, a mixture of sulfuric acid and phosphoric acid or a sulfuric acid or mixture of sulfuric acid and phosphoric acid containing sulfate, hydrogen sulfate, phosphate or hydrogen phosphate of ammonium, aluminum, iron, vanadium, manganese, molybdenum, chromium, copper and/or cobalt, and moldings are formed from this mixture, or the mixture of the solid primary material is formed into moldings after the addition of fluid and/or phosphoric acid and/or phosphates, and these moldings are treated with sulfuric acid or a sulfuric acid containing sulfate or hydrogen sulfate of ammonium, aluminum, iron, vanadium, manganese, molybdenum, ch…