Plenty of diesel particulate matter (PM) is emitted into the atmosphere in the forms of raw PM and partially oxidized PM. Comprehensive investigations of PM oxidation behavior and kinetics contribute to lower PM emission and optimize the PM capture device design. In this paper, diesel PM oxidation behavior was investigated using different temperature control programs, then, the oxidation kinetics were analyzed using Arrhenius equation. Nanostructure, Fourier Transform Infrared Spectroscopy (FTIR) and Raman characteristics were adopted to further clarify PM oxidation kinetics. The results indicated that PM oxidation showed multi-stage reactions, and reaction rate decreased rapidly in the isothermal process, with activation energy increasing. Heat transfer limitation significantly decreased the activation energy, also affected the following reactions. In the narrow temperature range 523°C~537°C, the activation energy of partially oxidized and aging PM was smaller than the values of the initial oxidation stage. The oxidation transformation phase had a huge potential of evolving into the heat transfer limitations. The activation energy of partially oxidized and aging PM was smaller than the value of raw PM at the end of oxidation, which was caused by the catalytic reaction of metal ash. Diesel PM nanostructure changed from the onion like to core-shell like structures after partial oxidation.
CORE (COnnecting REpositories)
CORE (COnnecting REpositories)