In:
Atmospheric Chemistry and Physics, Copernicus GmbH, Vol. 19, No. 12 ( 2019-06-20), p. 8063-8081
Abstract:
Abstract. Gasoline evaporative emissions have become an important anthropogenic source
of urban atmospheric volatile organic compounds (VOCs) and secondary organic
aerosol (SOA). These emissions have a significant impact on regional air
quality, especially in China where car ownership is growing rapidly.
However, the contribution of evaporative emissions to secondary aerosol
(SA) is not clear in an air pollution complex in which a high concentration of
SO2 and NH3 was present. In this study, the effects of SO2
and NH3 on SA formation from unburned gasoline vapor were investigated
in a 30 m3 indoor smog chamber. It was found that an increase in SO2
and NH3 concentrations (0–151 and 0–200 ppb, respectively)
could linearly promote the formation of SA, which could be enhanced by a
factor of 1.6–2.6 and 2.0–2.5, respectively. Sulfate was most sensitive
to the SO2 concentration, followed by organic aerosol, which was due
not only to the acid catalytic effect, but was also related to the formation of
organic sulfur-containing compounds. In the case of an increasing NH3
concentration, ammonium nitrate increased more significantly than organic
aerosol, and nitrogen-containing organics were also enhanced, as revealed by
the results of positive matrix factorization (PMF) analysis. New particle
formation (NPF) and particle size growth were also significantly enhanced in
the presence of SO2 and NH3. This work indicates that gasoline
evaporative emissions will be a significant source of SA, especially in the
presence of high concentrations of SO2 and NH3. Meanwhile, these
emissions might also be a potential source of sulfur- and
nitrogen-containing organics. Our work provides a scientific basis for the
synergistic emission reduction of secondary aerosol precursors, including
NOx, SO2, NH3, and particularly VOCs, to mitigate particulate matter (PM) pollution
in China.
Type of Medium:
Online Resource
ISSN:
1680-7324
DOI:
10.5194/acp-19-8063-2019
DOI:
10.5194/acp-19-8063-2019-supplement
Language:
English
Publisher:
Copernicus GmbH
Publication Date:
2019
detail.hit.zdb_id:
2092549-9
detail.hit.zdb_id:
2069847-1
