Chemical kinetic study of a novel lignocellulosic biofuel: Di-n-butyl ether oxidation in a laminar flow reactor and flames
Egolfopoulos, Fokion N.
Pitsch, Heinz G.
Westbrook, Charles K.
KAUST DepartmentClean Combustion Research Center
Physical Sciences and Engineering (PSE) Division
Chemical and Biological Engineering Program
MetadataShow full item record
AbstractThe combustion characteristics of promising alternative fuels have been studied extensively in the recent years. Nevertheless, the pyrolysis and oxidation kinetics for many oxygenated fuels are not well characterized compared to those of hydrocarbons. In the present investigation, the first chemical kinetic study of a long-chain linear symmetric ether, di-n-butyl ether (DBE), is presented and a detailed reaction model is developed. DBE has been identified recently as a candidate biofuel produced from lignocellulosic biomass. The model includes both high temperature and low temperature reaction pathways with reaction rates generated using appropriate rate rules. In addition, experimental studies on fundamental combustion characteristics, such as ignition delay times and laminar flame speeds have been performed. A laminar flow reactor was used to determine the ignition delay times of lean and stoichiometric DBE/air mixtures. The laminar flame speeds of DBE/air mixtures were measured in the stagnation flame configuration for a wide rage of equivalence ratios at atmospheric pressure and an unburned reactant temperature of 373. K. All experimental data were modeled using the present kinetic model. The agreement between measured and computed results is satisfactory, and the model was used to elucidate the oxidation pathways of DBE. The dissociation of keto-hydroperoxides, leading to radical chain branching was found to dominate the ignition of DBE in the low temperature regime. The results of the present numerical and experimental study of the oxidation of di-n-butyl ether provide a good basis for further investigation of long chain linear and branched ethers. © 2013 The Combustion Institute.
SponsorsThe authors are grateful to Dr. Mariam Al Rashidi (KAUST, Saudi Arabia) and Dr. Alex Davis (NIST, USA) for performing the quantum chemical BDE calculations. This work was performed as part of the Cluster of Excellence "Tailor-Made Fuels from Biomass", which is funded by the Excellence Initiative by the German federal and state governments to promote science and research at German universities, and as part of the collaborative research center (SFB) 1029 which is funded by the German Research Foundation (DFG). This work was partly funded by the Clean Combustion Research Center at the King Abdullah University of Science and Technology. Co-author S.M.S. acknowledges funding from the TMFB Visiting Fellowship program. The LLNL work was performed under the auspices of the US Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. The USC work was supported as part of the CEFRC, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, and Office of Basic Energy Sciences under Award Number DE-SC0001198.
JournalCombustion and Flame