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Anthony
M. Dean
William K. Coors Distinguished Professor
B.S.
Chemistry, Spring Hill College
A.M. Physical Chemistry, Harvard University
Ph.D. Physical Chemistry, Harvard University
Free radical
kinetics, coupling kinetics and transport, solid-oxide fuel cells
Research Description
Dean Research
Group Page
Publications
Experience
Contact Information
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Research
Description
The efforts of our research team focus on the quantitative kinetic characterization
of reaction systems, especially those where the kinetics and transport
are coupled. For example, we are interested in the reactions that occur
in high-temperature solid oxide fuel cells (SOFCs). These gas-phase reactions
in the fuel-channel produce intermediates that can profoundly influence
fuel cell performance. We seek to understand the detailed chemical pathways
that lead to production of the smaller hydrocarbons that might be electrochemically
oxidized, as well as the molecular weight growth processes that can lead
to deposit formation within the anode channels. These reactions are strongly
influenced by multiple transport processes including diffusion and reaction
of the gaseous hydrocarbons as they migrate through the porous anode.
Once we characterize the gas-phase kinetics and the catalytic kinetics
occurring within the porous anode, we can include these reactions into
the combined transport-kinetic models needed for optimization of fuel
cell performance.
Another area of interest is low temperature hydrocarbon ignition, especially
in the temperature regime of the "negative temperature coefficient",
where the ignition delay increases as the temperature increases. Understanding
the ignition kinetics is essential to be able to reliably characterize
events such as ignition in a HCCI (homogeneous charge compression ignition)
engine. As with the fuel cell, transport effects (here due to temperature
gradients within the cylinder) play a critical role in the ignition timing.
To better characterize the kinetics, we are focusing on a detailed analysis
of the reactions between alkyl radicals and molecular oxygen. We incorporate
the results from these detailed analyses into existing mechanisms to
generate improved descriptions of the ignition process. These improved
mechanisms can then be used to suggest combinations of fuel and engine
conditions that should lead to more robust operation of the HCCI engine.
A new research area for our group concerns the production of fuel cell
fuels from renewable resources, specifically biomass. In particular,
we are interested in understanding the gas-phase reactions that lead
to tar formation during biomass gasification. Such understanding can
lead to identification of optimum residence time-temperature combinations
that minimize tar formation, thus substantially simplifying the clean-up
needed.
Current
Research Projects:
• Fundamental Chemistry and Physics of Direct-Oxidation in Solid-Oxide
Fuel Cells (ONR MURI)
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Modeling and Simulation Tools for Chemical and Electrochemical Systems:
Bridging Between Atomistic Fundamentals and System Engineering (ONR)
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Hydrocarbon Ignition Kinetics
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Thermal Cracking of Tar Model Compounds in Biomass-Derived Vapors (NREL)
Experience
Senior Research Associate, ExxonMobil Research and Engineering Co. 1990-2000
Research Associate, Exxon Research and Engineering Co. 1982-1990
Senior Staff Chemist, Exxon Research and Engineering Co., 1979-1982
Associate Professor, Chemistry Dept., University of Missouri-Columbia
1975-1979
Associate Chairman, University of Missouri-Columbia 1977-1979
Assistant
Professor, University of Missouri-Columbia 1970-1975
Recent
Professional Activities:
Panel for Chemical Science and Technology of the Board of Assessment
of NIST programs, 1994-1999 Scientific
Advisory Committee for the EPA Center on Airborne Organics, 1992-
Chemical Physics
Program Review, Lawrence Berkeley National Lab, 2000 Board
of Directors of the Combustion Institute, 1996- Member:
ACS, AIChE, Combustion Institute, ASEE
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