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The high-temperature, high-pressure pyrolysis of the prototype aromatic, benzene, has been studied behind reflected shock waves in the UIC High Pressure Single Pulse Shock Tube. Three sets of experiments were performed at nominal pressures of 30 and 50 bars in the high temperature regime from 1200–1800 K. Stable species sampled from the shock tube were analyzed offline using gas chromatographic techniques. The present data set was simulated using the three most recent models, two of the models developed and validated against high-temperature benzene pyrolysis shock-tube data for stable species profiles as well as H atom production rates and the third model, a “work-in-progress” model from our laboratory aimed at resolving the high-pressure combustion of primary aromatics such as benzene and toluene. The simulations reflect the complexities and uncertainties involved not only in describing the primary decay steps but also the subsequent high-temperature secondary chemistry for even the simplest aromatic molecule, benzene. [ABSTRACT FROM AUTHOR]

Abstract: A detailed chemical kinetic model has been developed to predict the oxidation of toluene in the high temperature regime (1200–1500K) over wide pressure ranges (25–610bar) based on experimental data obtained in the high pressure single pulse shock tube at the University of Illinois at Chicago. The experimental data were obtained at pressures of 25, 50, and 610bar over the temperature range from 1210 to 1480K for stoichiometries of ? =1 and ? =5. The proposed model is derived from an earlier literature model for toluene oxidation that had been validated against experimental data obtained at 1atm and at lower temperatures (<1200K). The new model provides a good fit to all the experimental data for stoichiometric oxidation but provides a less satisfactory fit to the ? =5 (fuel-rich) data set and forms the first step in the development of a more comprehensive model for toluene combustion for fuel-rich oxidation and pyrolysis. [Copyright &y& Elsevier]

Abstract: The high-pressure single pulse shock tube (HPST) at the University of Illinois at Chicago has been used to study the oxidation of toluene at reflected shock pressures from 22 to 550 bar and temperatures from 1210 to 1480 K. Experiments were performed for dilute stoichiometric, , and rich, , reagent mixtures. Stable species were analyzed using gas chromatography and gas chromatography/mass spectrometry. The resulting data set is the first that provides species concentrations over such extremes of pressure, temperature, and stoichiometry, and it serves as an excellent base for the validation and refinement of future detailed chemical kinetic models. Two literature models for the oxidation of toluene that have been validated against atmospheric pressure turbulent flow reactor and jet stirred reactor data were used to simulate the experimental data. Several modifications were made to one model to more accurately simulate the high-pressure/high-temperature experimental data. The modified model reproduces the experimental data well and forms the first step in the development of a more comprehensive model for toluene combustion validated over wide ranges of temperature and pressure. [Copyright &y& Elsevier]