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:
May. 05, 1998
Filed:
Jul. 30, 1996
Mikio Murachi, Toyota, JP;
Seiji Okawara, Susono, JP;
Koichi Kojima, Susono, JP;
Takuya Kondo, Susono, JP;
Toyota Jidosha Kabushiki Kaisha, Toyota, JP;
Abstract
According to the method of the present invention, NO (nitrogen monoxide) in the exhaust gas of a diesel engine is first oxidized to NO.sub.2 (nitrogen dioxide) by an oxidizing catalyst. Further, carbon particles in the exhaust gas are trapped by a DPF (diesel particulate filter). The exhaust gas containing NO.sub.2 formed by oxidation of nitrogen monoxide is, then, fed to the DPF, and NO.sub.2 in the exhaust gas reacts with the carbon particles trapped in the DPF. When the NO.sub.2 reacts with carbon particles, carbon particles are oxidized (burned) by NO.sub.2 and removed from DPF, and, at the same time, NO.sub.2 is reduced to NO by the carbon particles. The exhaust gas containing NO formed by the reaction between the carbon particles and NO.sub.2 is fed to an NO.sub.X absorbent. In the NO.sub.X absorbent, NO is absorbed by the NO.sub.X absorbent and, thereby, removed from the exhaust gas. Therefore, according this method, the carbon particles collected by the DPF can be easily burned by NO.sub.2, thereby being removed from the DPF without increasing the amount of NO released to the atmosphere.