Effect of Fuel Compositions on PAH in Particulate Matter from DI Diesel Engine

The effects of fuel properties on poly aromatic hydrocarbons (PAHs) in particulate matter from the latest DI diesel engine were investigated under the Japanese 13 mode test cycle. It was found that the deeply desulfurized fuel had large effect on reducing PAH emissions. Furthermore, the reduction of PAH emissions was observed in the case of kerosene blend on the high sulfur fuel. However, the reduction of PAH emissions due to kerosene blend was not so large in the deeply desulfurized fuel. From the test using special fuel of which target property only changed under keeping the rest propeties constant, it was suggested that poly aromatics in the fuel affected PAH emissions and the influence of tri-aromatics in the fuel was promoted by the coexistence of mono-aromatics or naphthene. PAH formation scheme from each fuel component was proposed by chemical thermodynamic data.