The formation of benzene in a series of fuel-rich premixed reaotant systems with a constant carbon-to-oxygen ratio of approximately 0.6 is investigated experimentally in a laminar flow reactor at temperatures between 1073 and 1823 K and at atmospheric pressure. The experimental data are compared to model results using a chemical kinetic mechanism based on the work of Pope and Miller. Modifications to their mechanism include changes in the reaction subsets of C_2H_2, C_3H_4, and 1,3-C_4H_6. The experimental data show that benzene formation may exhibit two distinct peaks as a function of the reaction temperature. A high-temperature peak is observed between 1500 and 1600 K, and it appears with a similar magnitude of concentration for all sets of reactants. A low-temperature peak is observed between 1200 and 1300 K for reactant sets CH_4/C_2H_2, CH_4/C_3H_4, and CH_4/1,3-C_4H_6. The low-temperature peak is comparable in magnitude for the CH_4/C_2H_2 and CH_4/1,3-C_4H_6 mixtures, while it is 5 times larger in the CH_4/C_3H_4 system. In general, there is good agreement between modeling and experimental results. However, some improvements are needed, in particular in the acetylene chemistry and the initiation kinetics for 1,3-butadiene.
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