Effect of acetone-butanol-ethanol addition to diesel on the soot reactivity

The ability of acetone-butanol-ethanol (ABE) to reduce pollutant emissions has been validated in recent studies. In this study, the effect of addition of ABE (up to 30% by volume) to diesel on the soot oxidation reactivity was investigated to further evaluate the feasibility of increasing the particulate filter regeneration rate. The oxidation activities of soot samples were compared using the average activation energies calculated from the thermal gravimetric curves. It was found that the average activation energies of the ABE-diesel-blends-derived soot are lower than that of diesel-derived soot. The variations in the physical and chemical properties of the soot samples were investigated to determine the parameters that improve the soot oxidation reactivity. Several experimental diagnostic techniques, such as Fourier transform infrared spectroscopy, elemental analysis, X-ray diffraction, and high-resolution transmission electron microscopy, were used to investigate the changes in the functional groups, atomic O/C and H/C ratios, nanocrystallite parameters, and soot nanostructures. With increasing concentration of ABE in diesel, the size of the primary particles, nanocrystallite length, and amount of aromatic C=C functional groups in the soot decrease, while the nanocrystallites tortuosity, amount of oxygenated functional groups, and atomic O/C and H/C ratios increase. The changes of these parameters prove the higher reactivity of ABE-diesel-blends-derived soot.