NO2 oxidation reactivity and burning mode of diesel particulates
- Texas A & M Univ., College Station, TX (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
- Penn State Univ., University Park, PA (United States)
- Texas A & M Univ., College Station, TX (United States)
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
The NO2 oxidation kinetics and burning mode for diesel particulate from light-duty and medium-duty engines fueled with either ultra low sulfur diesel or soy methyl ester biodiesel blends have been investigated and are shown to be significantly different from oxidation by O2. Oxidation kinetics were measured using a flow-through packed bed microreactor for temperature programmed reactions and isothermal differential pulsed oxidation reactions. The burning mode was evaluated using the same reactor system for flowing BET specific surface area measurements and HR-TEM with fringe analysis to evaluate the nanostructure of the nascent and partially oxidized particulates. The low activation energy measured, specific surface area progression with extent of oxidation, HR-TEM images and difference plots of fringe length and tortuosity paint a consistent picture of higher reactivity for NO2, which reacts indiscriminately immediately upon contact with the surface, leading to the Zone I or shrinking core type oxidation. In comparison, O2 oxidation is shown to have relatively lower reactivity, preferentially attacking highly curved lamella, which are more reactive due to bond strain, and short lamella, which have a higher proportion of more reactive edge sites. Furthermore, this preferential oxidation leads to Zone II type oxidation, where solid phase diffusion of oxygen via pores contributes significantly to slowing the overall oxidation rate, by comparison.
- Research Organization:
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Fuels, Engines and Emissions Research Center (FEERC); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). National Transportation Research Center (NTRC)
- Sponsoring Organization:
- USDOE Office of Energy Efficiency and Renewable Energy (EERE)
- Grant/Contract Number:
- AC05-00OR22725
- OSTI ID:
- 1261321
- Journal Information:
- Topics in Catalysis, Vol. 59, Issue 8-9; ISSN 1022-5528
- Publisher:
- SpringerCopyright Statement
- Country of Publication:
- United States
- Language:
- English
Web of Science
Similar Records
Nanostructure and burning mode of light-duty diesel particulate with conventional diesel, biodiesel, and intermediate blends
Impacts of advanced diesel combustion operation and fuel formulation on soot nanostructure and reactivity