ChBE Seminar Series: Tony Dean, CO School of Mines
Speaker: Anthony M. Dean, Emeritus Professor of the Chemical Engineering Dept., Colorado School of Mines
Title: Development and Application of Detailed Kinetic Models
The improved understanding of elementary chemical reactions has markedly improved our ability to quantitatively characterize “real-world” systems. Such improvements require development of accurate, detailed chemical mechanisms, which in turn requires careful analysis of the different types of elementary reactions incorporated into the mechanisms. This talk will describe our approach to the characterization of elementary reactions and the construction of detailed mechanisms. We will focus on the development of rate rules for various types of free radical reactions. Applications of these approaches to describe several hydrocarbon pyrolysis and oxidation systems will be presented. One such system is alkene pyrolysis. Alkenes are components in hydrocarbon fuels, and they are also key intermediates during the decomposition of alkanes, alcohols, ethers, and biofuels. Thus, their subsequent reactions will have substantial impact on the final product distribution. More specifically, alkenes, unlike alkanes, can undergo radical addition reactions that then may lead to formation of higher molecular weight growth (MWG) species, perhaps leading to deposit formation. We will summarize a combined experiment-modeling effort to describe the pyrolysis kinetics of propene and the three butene isomers. This model accurately describes fuel decay, major products formation, and generation of the major molecular weight growth products. The similarities and differences among these fuels will be discussed in terms of the impact of their structures. Many applications of interest also require an analysis of the impact of transport on the chemical kinetics. This will generally require a substantial reduction in the size of the mechanism. One example to be discussed considered the impact of droplet evaporation on counter-flow diffusion flames.
Tony Dean retired as Senior Vice President for Research and Technology Transfer at the Colorado School of Mines in June 2017. He is still active in research as an Emertius Professor in the Chemical Engineering Deptartment, with a focus on the development of rate rules for elementary chemical reactions that are based upon high-level electronic structure calculations. These rules are then applied to the development of detailed chemical mechanisms for pyrolysis and oxidation of fuels, with particular emphasis on the impact of fuel structure on conversion and selectivity. He had previously served as Dean of the College of Applied Science and Engineering at CSM from 2012-2014. He joined Mines in 2000 as the W. K. Coors Distinguished Professor in the Chemical Engineering Department. In 2008, he received the Dean’s Excellence Award from CSM. In 2012, he received the Colorado Section Award from the American Chemical Society. From 1979-2000, he worked in the Corporate Research Labs at Exxon Research and Engineering where his group developed quantitative kinetic mechanisms to characterize fuel reactivity in engines and other high-temperature reactors such as steam crackers. He was a faculty member and Associate Chairman in the Chemistry Department at the University of Missouri-Columbia (1970-79). He has served on the boards of the Combustion Institute, the Colorado Energy Research Collaboratory, and the Alliance for Sustainable Energy. He received his Ph.D. in Physical Chemistry from Harvard University in 1971.