Regulated and unregulated emissions from a 2-stroke and a 4-stroke scooter were characterized during a legislative driving cycle in a certified laboratory. Scooter exhaust was analyzed at the tailpipe, in a dilution tunnel, and partly collected in a mobile smog chamber for photochemical aging. We present evidence that the photochemically aged exhaust from a 2-stroke and a 4-stroke scooter produces considerable amounts of secondary organic aerosol: from 1.5 to 22.0 mg/km, and from 5.5 to 6.6 mg/km, respectively. Tests were repeated after replacing the standard petrol and synthetic lube oil with an alkylate fuel (with low content of aromatic compounds) and ultra-clean lube oil (low ash forming potential). We observed emission reduction (with some exceptions) for several gaseous and particulate phase species, in particular for carbon monoxide (from 8% up to 38% and from 31% to 50%, for the 2-stroke and the 4-stroke scooters, respectively), particulate mass (from 32% up to 75% for the 2-stroke scooter), aromatic compounds (89% and 97% for the 2-stroke and the 4-stroke scooter, respectively), and secondary organic aerosol (from 87% to 100% and 99% for the 2-stroke and the 4-stroke scooters, respectively). We attribute the organic aerosol reduction to the low content of aromatics in the alkylate fuel.

ZARDINI Alessandro;  PLATT Stephen;  CLAIROTTE Michael;  HADDAD Imad;  TEMIME-ROUSSEL Brice;  MARCHAND Nicholas;  JEZEK Irena;  DRINOVEC Luka;  MOCNIK Grisa;  SLOWIK Jay;  MANFREDI Urbano;  PREVOT Andre S. H.;  BALTENSPERGER Urs;  ASTORGA-LLORENS Maria; 

2014-06-04

PERGAMON-ELSEVIER SCIENCE LTD

JRC84288

1352-2310,   

http://www.sciencedirect.com/science/article/pii/S1352231014001952,    https://publications.jrc.ec.europa.eu/repository/handle/JRC84288,   

10.1016/j.atmosenv.2014.03.024,