Catalyst Aging and Effects on Particle Emissions of 2-Stroke Scooters 2008-01-0455
An active oxidation catalyst is an efficient measure to reduce not only gaseous components (CO, HC), but also particle emissions (mostly oil condensates) of a small 2-stroke engine with lost oil lubrication.
Since the 2- and 3-wheelers with 2-stroke propulsion are still a very serious source of air pollution worldwide in many urban areas, it is important to have a look on some consequences of an improperly working catalyst.
The present paper shows some results of user-oriented aging of catalyst on the vehicle and results of limited emissions and unlimited (nano)particles during the catalysts screening tests.
The works are a part of an international scooter network project, which was performed (2004 to 2007) in the Laboratories for IC-Engines & Exhaust Emission Control of the University of Applied Sciences, Biel, Switzerland with main support of the Swiss Federal Office of Environment (BAFU), Swiss Petrol Union (EV) and Swiss Lubes (VSS).
A catalyst, which is polluted by oil overdosing, becomes a longer light-off time and lower conversion rates. A part of this deterioration is irreversible. An inactive catalyst causes clearly higher gaseous and particulate emission components.