TY - JOUR
T1 - Origin and transformation of ambient volatile organic compounds during a dust-to-haze episode in northwest China
AU - Xue, Yonggang
AU - Huang, Yu
AU - Sai Hang Ho, Steven
AU - Chen, Long
AU - Wang, Liqin
AU - Lee, Shuncheng
AU - Cao, Junji
N1 - Funding Information:
Acknowledgements. Yu Huang was also supported by the “Hundred Talent Program” of the Chinese Academy of Sciences. The authors gratefully acknowledge the NOAA Air Resources Laboratory (ARL) for the provision of the HYSPLIT transport and dispersion model and the READY website (https://www.ready.noaa.gov, last access: 30 April 2020) used in this publication. The data used are listed in the Supplement.
Funding Information:
Financial support. This research has been supported by the Na-
Funding Information:
tional Key Research and Development Program of China (grant nos. 2017YFC0212200 and 2016YFA0203000), the National Natural Science Foundation of China (grant nos. 41701565, 21661132005, and 41573138), and the Strategic Priority Research Program of the Chinese Academy of Sciences, China (grant no. XDA23010).
Publisher Copyright:
© Author(s) 2020.
Copyright:
Copyright 2020 Elsevier B.V., All rights reserved.
PY - 2020/5/8
Y1 - 2020/5/8
N2 - The high contribution of secondary organic aerosol to the loading of fine particle pollution in China highlights the roles of volatile organic compound (VOC) oxidation. In this respect, particulate active metallic oxides in dust, like TiO2 and Fe ions, were proposed to influence the photochemical reactions of ambient VOCs. A case study was conducted at an urban site in Xi'an, northwest China, to investigate the origin and transformation of VOCs during a windblown dust-to-haze pollution episode, and the assumption that dust would enhance the oxidation of VOCs was verified. Local vehicle exhaust (25 %) and biomass burning (18 %) were found to be the two largest contributors to ambient VOCs. In the dust pollution period, a sharp decrease in the loading of VOCs and the aging of their components were observed. Simultaneously, the secondary oxygenated VOC fraction (i.e., methylglyoxal) increased. Source strength, physical dispersion, and regional transport were eliminated as major factors for the variation of ambient VOCs. In another aspect, about a 2- to 3-fold increase in the loading of iron (Fe) and titanium (Ti) was found in the airborne particles, together with a fast decrease in trans-/cis-2-butene ratios, which demonstrated that dust can accelerate the oxidation of ambient VOCs and the formation of secondary organic aerosol (SOA) precursors..
AB - The high contribution of secondary organic aerosol to the loading of fine particle pollution in China highlights the roles of volatile organic compound (VOC) oxidation. In this respect, particulate active metallic oxides in dust, like TiO2 and Fe ions, were proposed to influence the photochemical reactions of ambient VOCs. A case study was conducted at an urban site in Xi'an, northwest China, to investigate the origin and transformation of VOCs during a windblown dust-to-haze pollution episode, and the assumption that dust would enhance the oxidation of VOCs was verified. Local vehicle exhaust (25 %) and biomass burning (18 %) were found to be the two largest contributors to ambient VOCs. In the dust pollution period, a sharp decrease in the loading of VOCs and the aging of their components were observed. Simultaneously, the secondary oxygenated VOC fraction (i.e., methylglyoxal) increased. Source strength, physical dispersion, and regional transport were eliminated as major factors for the variation of ambient VOCs. In another aspect, about a 2- to 3-fold increase in the loading of iron (Fe) and titanium (Ti) was found in the airborne particles, together with a fast decrease in trans-/cis-2-butene ratios, which demonstrated that dust can accelerate the oxidation of ambient VOCs and the formation of secondary organic aerosol (SOA) precursors..
UR - http://www.scopus.com/inward/record.url?scp=85084733306&partnerID=8YFLogxK
U2 - 10.5194/acp-20-5425-2020
DO - 10.5194/acp-20-5425-2020
M3 - Journal article
AN - SCOPUS:85084733306
SN - 1680-7316
VL - 20
SP - 5425
EP - 5436
JO - Atmospheric Chemistry and Physics
JF - Atmospheric Chemistry and Physics
IS - 9
M1 - 2020
ER -