ACPD Atmospheric Chemistry and Physics Discussions ACPD Atmos. Chem. Phys. Discuss. 1680-7375 Göttingen, Germany 10.5194/acpd-14-16591-2014 Emissions of organic aerosol mass, black carbon, particle number, and regulated and unregulated gases from scooters and light and heavy duty vehicles with different fuels Chirico R. 1 2 Clairotte M. 3 Adam T. W. 3 Giechaskiel B. 3 6 Heringa M. F. 1 Elsasser M. 4 5 Martini G. 3 Manfredi U. 3 Streibel T. 5 Sklorz M. 5 Zimmermann R. 4 5 DeCarlo P. F. https://orcid.org/0000-0001-6385-7149 1 7 Astorga C. 3 Baltensperger U. https://orcid.org/0000-0003-0079-8713 1 Prevot A. S. H. 1 Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, 5232 Villigen PSI, Switzerland Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA), UTAPRAD-DIM, Via E. Fermi 45 – 00044 Frascati (RM), Italy European Commission, Joint research Centre (JRC), Institute for Energy and Transport (IET), Sustainable Transport Unit, Via Enrico Fermi 2749, 21027 Ispra VA, Italy Cooperation Group Comprehensive Molecular Analytics (CMA)/Joint Mass Spectrometry Centre, Helmholtz Zentrum München, 85764 Neuherberg, Germany Chair of Analytical Chemistry/Joint Mass Spectrometry Centre, Institute of Chemistry, University of Rostock, 18051 Rostock, Germany AVL List GmbH, Hans-List-Platz 1, Graz, Austria now at: Department of Civil, Architectural, and Environmental Engineering and Department of Chemistry, Drexel University, Drexel University, Philadelphia, USA 24 06 2014 14 11 16591 16639 Copyright: © 2014 R. Chirico et al. 2014 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://acp.copernicus.org/preprints/14/16591/2014/acpd-14-16591-2014.html The full text article is available as a PDF file from https://acp.copernicus.org/preprints/14/16591/2014/acpd-14-16591-2014.pdf

A sampling campaign with seven different types of vehicles was conducted in 2009 at the vehicle test facilities of the Joint Research Centre (JRC) in Ispra (Italy). The vehicles chosen were representative of some categories circulating in Europe and were fueled either with standard gasoline or diesel and some with blends of rapeseed methyl ester biodiesel. The aim of this work was to improve the knowledge about the emission factors of gas phase and particle-associated regulated and unregulated species from vehicle exhaust. Unregulated species such as black carbon (BC), primary organic aerosol (OA) content, particle number (PN), monocyclic and polycyclic aromatic hydrocarbons (PAHs) and a~selection of unregulated gaseous compounds, including nitrous acid (N<sub>2</sub>O), ammonia (NH<sub>3</sub>), hydrogen cyanide (HCN), formaldehyde (HCHO), acetaldehyde (CH<sub>3</sub>CHO), sulfur dioxide (SO<sub>2</sub>), and methane (CH<sub>4</sub>), were measured in real time with a suite of instruments including a high-resolution aerosol time-of-flight mass spectrometer, a resonance enhanced multi-photon ionization time-of-flight mass spectrometer, and a high resolution Fourier transform infrared spectrometer. Diesel vehicles, without particle filters, featured the highest values for particle number, followed by gasoline vehicles and scooters. The particles from diesel and gasoline vehicles were mostly made of BC with a low fraction of OA, while the particles from the scooters were mainly composed of OA. Scooters were characterized by super high emissions factors for OA, which were orders of magnitude higher than for the other vehicles. The heavy duty diesel vehicle (HDDV) featured the highest nitrogen oxides (NO<sub>x</sub>) emissions, while the scooters had the highest emissions for total hydrocarbons and aromatic compounds due to the unburned and partially burned gasoline and lubricant oil mixture. Generally, vehicles fuelled with biodiesel blends showed lower emission factors of OA and total aromatics than those from the standard fuels. The scooters were the main emitters of aromatic compounds, followed by the gasoline vehicle, the diesel vehicles and the HDDV.

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