[Characteristics of ambient VOCs and their role in O3 formation: a typical air pollution episode in Shanghai urban area].

Journal Article (Journal Article)

The concentration, speciation and chemical reactivity of ambient volatile organic compounds (VOCs) in shanghai city were analyzed and measured by using online gas chromatography with flame ionization detection systems (GC-FID) during a typical air pollution episode (from Oct. 30th to Nov. 2nd, 2010) and 55 kinds of VOCs were detected. The results show that averaged concentrations of VOCs was 27 x 10(-9) before the episode, and then dramatically increased by 3 times (87 x 10(-9)) in the episode than the former, the main components were alkanes (35.2 x 10(-9)), aromatics (30.0 x 10(-9)), alkenes (21.6 x 10(-9)). Furthermore, the maximum ozone formation potential (PhiOFP) is analyzed and showed that PhiOFP (in the episode) > PhiOFP (after the episode) PhiOFP (before the episode). Before the episode, the percent of PhiOFP for aromatics 53.0% , alkenes 36. 1% and alkanes 11.7%; in the episode, the percent of PhiOFP for aromatics 54.7%, alkenes 36.7% and alkanes 9.8%; after the episode, the percent of PhiOFP for alkenes 52.7%, aromatics 36.0% and alkanes 13.2%. Alkenes (C2-C4) and aromatics (C6-C8) are the main components for the ozone formation, namely toluene, m,p-xylene, 1,3-butadiene, propene, ethene et al. In addition, the relationship is negative and nonlinear between the O3 and PhiOFP. And efficiencies of PhiOFP formed into O3 are below 20. 0% in different stage of episode. This is very important and meaningful for the quantitative evaluate the influence of VOCs towards O3.

Duke Authors

Cited Authors

  • Cui, H-X; Wu, Y-M; Gao, S; Duan, Y-S; Wang, D-F; Zhang, Y-H; Fu, Q-Y

Published Date

  • December 2011

Published In

Volume / Issue

  • 32 / 12

Start / End Page

  • 3537 - 3542

PubMed ID

  • 22468514

International Standard Serial Number (ISSN)

  • 0250-3301

Language

  • chi