The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 18, 2005
Filed:
Apr. 20, 2001
Adolf Schäfer-sindlinger, Frankfurt, DE;
Marcus Pfeifer, Solingen, DE;
Paul Spurk, Bad König, DE;
Yvonne Demel, Frankfurt, DE;
Thomas Kreuzer, Karben, DE;
Egbert Lox, Hanau, DE;
Adolf Schäfer-Sindlinger, Frankfurt, DE;
Marcus Pfeifer, Solingen, DE;
Paul Spurk, Bad König, DE;
Yvonne Demel, Frankfurt, DE;
Thomas Kreuzer, Karben, DE;
Egbert Lox, Hanau, DE;
UMICORE AG & Co. KG, Hanau-Wolfgang, DE;
Abstract
A process for reducing the nitrogen oxides present in a lean exhaust gas from an internal combustion engine by selective catalytic reduction on a reduction catalyst using ammonia, wherein a fraction of the nitrogen monoxide present in the exhaust gas is oxidized to nitrogen dioxide before the exhaust gas, together with ammonia, is passed over the reduction catalyst. The reduction catalyst contains a zeolite exchanged with transition metals and oxidation of the nitrogen monoxide is performed in such a way that the exhaust gas contains 30 to 70 vol. % of nitrogen dioxide before contact with the reduction catalyst.