Oxidation catalyst

US8753999B2 · kind B2 · utility

Assignee

• HERAEUS PRECIOUS METALS GMBH & CO. KG · DE

Inventors

• Uwe Endruschat · Frankfurt, DE
• Ansgar Wille · Hannover, DE
• Prasanna Rajagopalan · Rostock, DE

Key dates

• Filing date: Jul 8, 2009
• Grant date: Jun 17, 2014
• Expiry date: Feb 13, 2031

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02A50/20
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

A catalyst for selective oxidation of hydrocarbons relative to carbon monoxide includes a mixed oxide based on the compound Ce0.1-0.5Ti0.2-0.8Cr0.1-0.5Ox, wherein x is (the total of the valences of the metals)/2. Preferably, the mixed oxide is fixed as a coating on a molded body or less than 0.5 wt. % precious metal is doped to the mixed oxide. Oxidizable exhaust-gas components are oxidized for exhaust-gas purification by a mixed oxide based on the compound Ce0.1-0.5Ti0.2-0.8Cr0.1-0.5Ox as the catalyst. Preferably, hydrocarbons are preferentially oxidized relative to carbon monoxides or nitrogen oxides. For producing an oxidation catalyst for internal combustion engines, a mixed oxide made of cerium oxide, titanium oxide, chromium oxide, and optionally other metal oxides is fixed to a metallic or oxide or carbide, high temperature-stable molded body or an oxide ceramic, wherein the oxide ceramic is fixed to a molded body. Preferably, here the molded body is a wire mesh or a honeycomb structure, or the oxide ceramic on which the mixed oxide is fixed is a wash coat. Within a combustion chamber and an exhaust-gas pipe or exhaust-gas return pipe connected to this combustion chamber, a …