Carbonyl and Nitrogen Dioxide Emissions From Gasoline- and Diesel-Powered Motor Vehicles
- 3 May 2008
- journal article
- research article
- Published by American Chemical Society (ACS) in Environmental Science & Technology
- Vol. 42 (11), 3944-3950
- https://doi.org/10.1021/es8002487
Abstract
Carbonyls can be toxic and highly reactive in the atmosphere. To quantify trends in carbonyl emissions from light-duty (LD) vehicles, measurements were made in a San Francisco Bay area highway tunnel bore containing essentially all LD vehicles during the summers of 1999, 2001, and 2006. The LD vehicle emission factor for formaldehyde, the most abundant carbonyl, did not change between 1999 and 2001, then decreased by 61 ± 7% between 2001 and 2006. This reduction was due to fleet turnover and the removal of MTBE from gasoline. Acetaldehyde emissions decreased by 19 ± 2% between 1999 and 2001 and by the same amount between 2001 and 2006. Absent the increased use of ethanol in gasoline after 2003, acetaldehyde emissions would have further decreased by 2006. Carbonyl emission factors for medium- (MD) and heavy-duty (HD) diesel trucks were measured in 2006 in a separate mixed-traffic bore of the tunnel. Emission factors for diesel trucks were higher than those for LD vehicles for all reported carbonyls. Diesel engine exhaust dominates over gasoline engines as a direct source of carbonyl emissions in California. Carbonyl concentrations were also measured in liquid-gasoline samples and were found to be low (2 showed a yearly rate of decrease for LD vehicle emissions similar to that of total NOx in this study. The observed NO2/NOx ratio was 1.2 ± 0.3% and 3.7 ± 0.3% for LD vehicles and diesel trucks, respectively.Keywords
This publication has 27 references indexed in Scilit:
- Effects of Fuel Ethanol Content and Volatility on Regulated and Unregulated Exhaust Emissions for the Latest Technology Gasoline VehiclesEnvironmental Science & Technology, 2007
- Ethanol Can Contribute to Energy and Environmental GoalsScience, 2006
- Real-world traffic emission factors of gases and particles measured in a road tunnel in Stockholm, SwedenAtmospheric Environment, 2004
- Decadal reductions of traffic emissions on a transit route in Austria – results of the Tauerntunnel experiment 1997Atmospheric Environment, 2001
- Relating Liquid Fuel and Headspace Vapor Composition for California Reformulated Gasoline Samples Containing EthanolEnvironmental Science & Technology, 2000
- Remote Sensing of NO and NO2 Emissions from Heavy-Duty Diesel Trucks Using Tunable Diode LasersEnvironmental Science & Technology, 2000
- Liquid Chromatography Analysis of Carbonyl (2,4-Dinitrophenyl)hydrazones with Detection by Diode Array Ultraviolet Spectroscopy and by Atmospheric Pressure Negative Chemical Ionization Mass SpectrometryAnalytical Chemistry, 1999
- Impact of Oxygenated Gasoline Use on California Light-Duty Vehicle EmissionsEnvironmental Science & Technology, 1996
- Nitrogen dioxide in exhaust emissions from motor vehiclesAtmospheric Environment (1967), 1987
- Characterization and analysis of diesel exhaust odorEnvironmental Science & Technology, 1987