System for reduction of harmful exhaust emissions from diesel engines

US6256984A · kind A · utility

Assignee

• Engelhard Corporation · US

Inventors

• Kenneth E. Voss · Iselin, US
• Timothy D. Wildman · Metamora, US
• Michael G. Norris · Manchester, US
• Gary W. Rice · Florence, US
• Anthony J. Rotolico · Hauppauge, US
• Arthur J. Fabel · Westbury, US
• Gerald L. Kutner · Town of West Hartford, US

Key dates

• Filing date: Sep 7, 1999
• Grant date: Jul 10, 2001
• Expiry date: Sep 7, 2019

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T428/12549
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

Methods and apparatus for reducing the TPM level of a diesel engine exhaust stream by providing a suitable oxidation catalyst into the exhaust train. The oxidation catalyst may be incorporated into a thermal insulative coating on the inner surface of the exhaust train, particularly the exhaust manifold and exhaust pipes prior to the turbocharger. Alternatively, when the exhaust train includes a turbocharger, the catalyst can be in a separate monolithic unit between the engine and the turbocharger. The system may also include an improved diesel oxidation catalyst unit having a metal monolithic substrate. The oxidation catalyst can also be incorporated into a thermal insulative coating inside the cylinders, particularly on non-rubbing surfaces such as The invention also includes the use of a protective mullite top coat on the thermal coating. A further embodiment is the use of a stainless steel bond coat to bind the thermal coating to a metallic substrate, particularly an aluminum substrate.