Arsenic-resistant mixed oxide catalyst and process for producing the same

US5112794A · kind A · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventors

• Erich Hums · Prüm, DE
• Gunther Spitznagel · Erlangen, DE

Key dates

• Filing date: Jun 21, 1990
• Grant date: May 12, 1992
• Expiry date: Jun 21, 2010

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B01J23/002
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

In an arsenic resistant mixed oxide catalyst and a process for producing the same, oxides of at least the metals vanadium and molybdenum are provided, especially for reducing nitrogen oxides in flue gases in the presence of a reducing agent such as ammonia and carbon monoxide. A MoO.sub.3 phase and at least one oxygen-rich mixed oxide phase such as V.sub.9 Mo.sub.6 O.sub.40 is at least partly converted into a mixed oxide phase being poorer in oxygen such as a V.sub.9 Mo.sub.4 O.sub.25 phase, for increasing arsenic resistance.