Volatile organic compounds emissions from gasoline and diesel powered vehicle

In this research, volatile organic compound emissions were characterized fr om gasoline and diesel vehicles. Sampling campaigns in the Metropolitan Are a of Mexico City were designed and carried out in tunnels, crossroads, and truck and bus terminals. The samples were analyzed with gas chromatography getting more than 250 different compounds, being more or less 60 of them th e 80% of all,the emissions. The most abundant are the two carbon compounds, as a result of the combustion, and compounds related to fuels composition, like isopentane, xylenes, toluene among others. The profiles obtained in t unnels and crossroads were very similar with the exception of the 3 and 4 c arbon compounds, which were found in bigger proportion in the profiles at c rossroads. This may probably be due to the blend with the ambient air. The profiles corresponding to trucks and buses have a smaller content of two ca rbon compounds and a bigger content of xylenes, toluene and ethylbenzene. T he variations in the proportion of the compounds allow to differentiate the profiles of vehicles using gasoline and diesel.