On-Road Emissions of Carbonyls from Light-Duty and Heavy-Duty Vehicles
详细信息 查看全文
- 作者：Daniel Grosjean ; Eric Grosjean ; and Alan W. Gertler
- 刊名：Environmental Science & Technology
- 出版年：2001
- 出版时间：January 1, 2001
- 年：2001
- 卷：35
- 期：1
- 页码：45 - 53
- 全文大小：77K
- 年卷期：v.35,no.1(January 1, 2001)
- ISSN：1520-5851
文摘
Vehicle emissions are a major source of carbonyls, whichplay an important role in atmospheric chemistry andurban air quality. Yet, little data are available for speciatedcarbonyls emitted by vehicles and especially by heavy-duty diesel vehicles. On-road vehicle emissions of carbonylshave been measured in May 1999 at the TuscaroraMountain Tunnel, PA. Ten saturated aliphatic aldehydes,4 saturated aliphatic ketones, 4 unsaturated aliphaticcarbonyls, 4 aliphatic dicarbonyls, and 9 aromatic carbonylshave been identified and their concentrations measured.For light-duty (LD) vehicles, total carbonyl emissions wereca. 6.4 mg/km, and the 10 largest emission factors were,in decreasing order, those of formaldehyde (2.58 ± 1.05 mg/km, ca. 40% of total carbonyls), acetone, acetaldehyde,heptanal, crotonaldehyde, 2-butanone, propanal, acrolein,methacrolein, and benzaldehyde. For weight class 7-8heavy-duty diesel vehicles (7-8 HD), total carbonyl emissionswere ca. 26.1 mg/km, and the 10 largest emission factorswere, in decreasing order, those of formaldehyde (6.73± 2.05 mg/km, ca. 26% of total carbonyls), acetaldehyde,acetone, crotonaldehyde, m-tolualdehyde, 2-pentanone,benzaldehyde, a C5 saturated aliphatic aldehyde isomer, 2,5-dimethylbenzaldehyde, and 2-butanone. Aromatic carbonyls,unsaturated aliphatic aldehydes, and aliphatic dicarbonylsrepresented larger fractions of the total carbonyl emissionsfor 7-8 HD vehicles than for LD vehicles. For HD vehicles,formaldehyde and acetaldehyde emission factors measuredin this study are ca. 4-5 times lower than those measuredin previous work. For LD vehicles, emission factorsmeasured in this study are generally lower than thosemeasured in earlier work and are about the same, withinreported uncertainties, as those measured in 1992 inthe same highway tunnel.