IMPACT OF ALTERNATIVE FUELS ON SOOT PROPERTIES AND DPF REGENERATION

In this work, fuel formulation exerted a strong influence on the properties of diesel particulates leading to differences in oxidation rate. These differences were especially significant when comparing soot derived from the combustion of soybean oil-derived biodiesel fuel (B100) and soot obtained from combustion of a Fischer-Tropsch diesel fuel (FT). These 2 fuels mainly differ in fuel oxygen content. Although B100 soot possesses an initially ordered structure, it is 5 times more oxidatively reactive than FT soot. While the initial structure alone does not dictate the reactivity of diesel soot, the relative amount of initial oxygen groups is the more important factor governing the oxidation rate than the initial structure and pore size distribution. Therefore, incorporation of greater surface oxygen functionality in the B100 soot provides the means for more rapid oxidation and thereby enables efficient regeneration of the diesel particulate filter.