HR: 0800h
AN: A51A-0025    [Abstracts]
TI: Chemical Composition of Aerosol Particles Emitted by a Passenger Car Engine Fueled by Ethanol/Gasoline Mixtures
AU: * Medrano, J M
EM: medranoj@carleton.edu
AF: Carleton College, Department of Chemistry 1 North College Street, Northfield, MN 55057, United States
AU: Gross, D S
EM: dgross@carleton.edu
AF: Carleton College, Department of Chemistry 1 North College Street, Northfield, MN 55057, United States
AU: Dutcher, D D
EM: ddutcher@me.umn.edu
AF: University of Minnesota, Department of Mechanical Engineering 111 Church Street SE, Minneapolis, MN 55455, United States
AU: Drayton, M
EM: dray0006@umn.edu
AF: University of Minnesota, Department of Mechanical Engineering 111 Church Street SE, Minneapolis, MN 55455, United States
AU: Kittelson, D
EM: kitte001@umn.edu
AF: University of Minnesota, Department of Mechanical Engineering 111 Church Street SE, Minneapolis, MN 55455, United States
AU: McMurry, P
EM: mcmurry@me.umn.edu
AF: University of Minnesota, Department of Mechanical Engineering 111 Church Street SE, Minneapolis, MN 55455, United States
AB: With concerns of national security, climate change, and human health, many people have called for oil independence for the United States and for the creation of alternative fuels. Ethanol has been widely praised as a viable alternative to petroleum-based fuels, due to the fact that it can be produced locally. A great deal of work has been done to characterize the energy balance of ethanol production versus consumption, but there have been fewer studies of the environmental and health impacts of emissions from combustion of ethanol/gasoline mixtures such as those burned in the modern vehicle fleet. To study the particulate emissions from such fuels, different ethanol/gasoline fuel mixtures with 0, 20, 40, and 85% ethanol were burned in a dynamometer-mounted automobile engine. The engine exhaust was diluted and sampled with two aerosol Time-of-Flight Mass Spectrometers (TSI 3800 ATOFMS), sampling different particle size ranges (50-500 nm and 150-3000 nm, respectively), to measure size and composition of the emitted aerosol particles. A variety of other aerosol characterization techniques were also employed to determine the size distribution of the aerosol particles, the mass emission rate from the engine, and the concentration of polycyclic aromatic hydrocarbons (PAHs) and elemental carbon (EC) in the particle emissions. Here we will focus on results from the ATOFMS, which provides us with a particle size and mass spectra - for both negative and positive ions - for each particle that is sampled. Particles being emitted were found to contain primarily PAHs, elemental carbon (EC), nitrates, and sulfates. Particles were analyzed to investigate trends in particle composition as a function of fuel ethanol content, particle size, and for the types of particles emitted. A trend in particle type as a function of fuel ethanol content was evident in smaller particles, and trends in composition as a function of particle size were visible across the entire size range sampled.
DE: 0305 Aerosols and particles (0345, 4801, 4906)
DE: 0345 Pollution: urban and regional (0305, 0478, 4251)
DE: 0394 Instruments and techniques
SC: Atmospheric Sciences [A]
MN: 2007 Fall Meeting