Online characterization of regulated and unregulated gaseous and particulate exhaust emission from two-stroke mopeds: A chemometric approach

Two-stroke mopeds are a popular and convenient mean of transport in particular in the highly populated cities but due to their engine technology, these vehicles can emit potentially toxic gaseous and aerosol pollutants. The legislative measurements of moped emissions are based on offline methods; however, the online characterization of gas and particulate phases presents a great interest to understand aerosol formation mechanism and to adapt the future emission standard. The purpose of this work was to study the emissions of two mopeds belonging to different European emission standards (EURO1 and EURO2). A sophisticated set of online analyzers was applied to monitor simultaneously the gas and particulate phase on a real time basis. The gaseous emission was analyzed with a Fourier transform infrared spectrometer (FTIR; Nitrogen species) and a resonance-enhanced multiphoton ionization time-of-flight mass spectrometer (REMPI-ToF-MS; polycyclic aromatic hydrocarbons : PAH), whereas the particulate phase was chemically characterized by a high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS; organic, nitrate and chloride aerosol) and a multiangle absorption photometer (MAAP; black carbon). The physical characterization of the aerosol was carried out with a condensation particle counter (CPC; particle number) and a Fast Mobility Particule Sizer (FMPS; size distribution). In order to extract underlying correlation between gas and solid emissions, a Principal Component Analysis was applied on the comprehensive online dataset. Multivariate analysis highlighted the considerable effect of the temperature on the particles and heavy PAH emission. The results showed that the after-treatment used to comply with the latest EURO2 emission standard may be responsible of the production of much more harmful unregulated aerosol compared to the EURO1 moped emission.

CLAIROTTE Michael;  ADAM Thomas W.;  CHIRICO Roberto;  GIECHASKIEL Barouch;  MANFREDI Urbano;  ELSASSER M.;  SKLORZ M.;  DECARLO Peter;  HERINGA M.F.;  ZIMMERMANN R.;  MARTINI Giorgio;  KRASENBRINK Alois;  VICET Aurore;  TOURNIÉ Eric;  PREVOT Andre S. H.;  ASTORGA-LLORENS Maria; 

2012-12-06

ELSEVIER SCIENCE BV

JRC61278

0003-2670,   

http://www.sciencedirect.com/science/article/pii/S0003267011016941,    https://publications.jrc.ec.europa.eu/repository/handle/JRC61278,   

10.1016/j.aca.2011.12.029,