Secondary organic aerosol formation from gasoline vehicle emissions in a new mobile environmental reaction chamber

We present a new mobile environmental reaction chamber for the simulation of the atmospheric aging of different emissions sources without limitation from the instruments or facilities available at any single site. Photochemistry is simulated using a set of 40 UV lights (total power 4 KW). Characterisation of the emission spectrum of these lights shows that atmospheric aging of emissions may be simulated over a range of temperatures (-7 to 25°C). A photolysis rate of NO2, JNO2, of (8.0±0.7)×10-3 s-1 was determined at 25°C. We demonstrate the utility of this new system by presenting results on the aging (OH=12×106 cm-3h) of emissions from a modern (Euro 5) gasoline car operated during a driving cycle (New European Driving Cycle, NEDC) on a chassis dynamometer in a vehicle test cell. Emissions from the entire NEDC were sampled and aged in the chamber. A thorough investigation of the composition of the gas phase emissions suggests that the observed SOA is from previously unconsidered precursors and processes. This large enhancement in PM mass from gasoline vehicle aerosol emissions due to SOA formation, if it occurs across a wider range of gasoline vehicles, would have significant implications for our understanding of the contribution of on-road gasoline vehicles to ambient aerosols.

PLATT Stephen;  HADDAD Imad;  ZARDINI Alessandro;  CLAIROTTE Michael;  ASTORGA-LLORENS Maria;  WOLF Robert;  SLOWIK Jay;  TEMIME-ROUSSEL Brice;  MARCHAND Nicholas;  JEZEK Irena;  DRINOVEC Luka;  MOCNIK Grisa;  MOEHLER O;  RICHTER H;  BARMET P.;  BIANCHI F;  BALTENSPERGER Urs;  PREVOT Andre S. H.; 

2013-10-01

COPERNICUS GESELLSCHAFT MBH

JRC84286

1680-7316,   

http://www.atmos-chem-phys.net/13/9141/2013/acp-13-9141-2013.pdf,    https://publications.jrc.ec.europa.eu/repository/handle/JRC84286,   

10.5194/acp-13-9141-2013,