Abstract:In order to remove the deposited particles inside diesel particulate filter (DPF) and realize the DPF regeneration, fuel borne catalyst (FBC) additive is thought to promote diesel particle combustion with the active metal component in fuel. FBC can reduce the particulate ignition temperature, and also decrease the peak temperature of regeneration process. Naphthenic acid cerium solution was selected as FBC, which was blended with diesel by the ratios of 50mg/kg, 100mg/kg, 150mg/kg and 300mg/kg (Ce mass fraction) and marked as F50, F100, F150 and F300, respectively. The particulate physicochemical properties of a common rail engine fueled with Ce-based FBC were studied by using thermosgravimetric analysis, gas chromatography/mass spectrometry (GC-MS), scanning electron microscopy (SEM) and staged sampling particulate system methods. The variations of oxidation susceptibility,soluble organic fraction (SOF) components, size distribution and microstructure of particulate with and without FBC were studied. Results showed that the oxidation reaction of particulate matter (PM) was moved to the low temperature area with the increase of FBC ratio, and the mass fraction of 150mg/kg for Ce was the optimal blending ratio. The ignition temperatures of PM combustion were reduced by 94℃, 131℃, 150℃ and 152℃, and the peak temperatures were reduced by 61℃, 123℃, 146℃ and 161℃ with the four FBC fuels. Before and after adding FBC, the mass fraction of SOF in PM sample were 29.6% and 24.1%, respectively. Compared with pure diesel PM sample, the high number of carbon atoms in SOF was decreased, and the polycyclic aromatic hydrocarbons (PAHs) were decreased by 49.2%. For FBC particle sample the particle sizes were moved towards small size direction, the peak number concentration of accumulation modal particle was decreased by 14.4%, the peak number concentration of nuclear modal particle was increased by 8.9%, and the peak mass concentration was decreased by 14.5%. FBC particle sample, which had porous sponge morphology and low bonding degree, contained 1.23% of Ce element.