[Source profile and chemical reactivity of volatile organic compounds from vehicle exhaust].
Light-duty gasoline taxis (LDGT) and passenger cars (LDGV), heavy-duty diesel buses (HDDB) and trucks (HDDT), gasoline motorcycles (MC) and LPG scooters (LPGS), were selected for tailpipe volatile organic compounds (VOCs) samplings by using transient dynamometer and on road test combined with SUMMA canisters technology. The samples were tested by GC-MS to analyze the concentration and species composition of VOCs. The results indicate that light-duty gasoline automobiles have higher fractions of aromatic hydrocarbons, which account for 43.38%-44.45% of the total VOCs, the main aromatic hydrocarbons are toluene and xylenes. Heavy-duty diesel vehicles have higher fractions of alkanes, which constitute 46.86%-48.57% of the total VOCs, the main alkanes are propane, n-dodecane and n-undecane. In addition, oxy-organics account for 13.28%-15.01% of the VOCs, the main oxy-organics is acetone. The major compound from MC and LPGS exhaust is acetylene, it accounts for 39.75% and 76.67% of the total VOCs, respectively. VOCs exhaust from gasoline motorcycles and light-duty gasoline automobiles has a significantly higher chemical reactivity than those from heavy-duty diesel vehicles, which contribute 55% and 44% to the atmospheric chemical reactivity in Shanghai. The gasoline motorcycles and light-duty gasoline automobiles are the key pollution sources affecting city and region ambient oxidation, and the key active species of toluene, xylenes, propylene, and styrene make the greatest contribution.
Shanghai Academy of Environmental Sciences, Shanghai 200233, China. qiaoyuezhen@hotmail.com
Yue-Zhen
YZ
Qiao
Hong-Li
HL
Wang
Cheng
C
Huang
Chang-Hong
CH
Chen
Lei-Yan
LY
Su
Min
M
Zhou
Hua
H
Xu
Gang-Feng
GF
Zhang
Yi-Ran
YR
Chen
Li
L
Li
Ming-Hua
MH
Chen
Hai-Ying
HY
Huang
D000393:Air Pollutants / Q000032:analysis*; D000475:Alkenes / Q000032:analysis; D002681:China; D002947:Cities; D004784:Environmental Monitoring; D014050:Toluene / Q000032:analysis; D001335:Vehicle Emissions / Q000032:analysis*; D055549:Volatile Organic Compounds / Q000032:analysis* / Q000737:chemistry; D014992:Xylenes / Q000032:analysis
D000393:Air Pollutants; D000475:Alkenes; D001335:Vehicle Emissions; D055549:Volatile Organic Compounds; D014992:Xylenes; D014050:Toluene; C013658:propylene