A comparative study of the formation of aromatics in rich methane flames doped by unsaturated compounds

Abstract

For a better modeling of the importance of the different channels leading to the first aromatic ring, we have compared the structures of laminar rich premixed methane flames doped with several unsaturated hydrocarbons: allene and propyne, because they are precursors of propargyl radicals which are well known as having an important role in forming benzene, 1,3-butadiene to put in evidence a possible production of benzene due to reactions of C 4 compounds, and, finally, cyclopentene which is a source of cyclopentadienylmethylene radicals which in turn are expected to easily isomerizes to give benzene. These flames have been stabilized on a burner at a pressure of 6.7 kPa (50 Torr) using argon as dilutant, for equivalence ratios (φ) from 1.55 to 1.79. A unique mechanism, including the formation and decomposition of benzene and toluene, has been used to model the oxidation of allene, propyne, 1,3-butadiene and cyclopentene. The main reaction pathways of aromatics formation have been derived from reaction rate and sensitivity analyses and have been compared for the three types of additives. These combined analyses and comparisons can only been performed when a unique mechanism is available for all the studied additives.

New chemical scheme for studying carbon-rich exoplanet atmospheres

“…This database has been used with success in modelling of premixed flame of butadiene, propyne, allene, and acetylene (Fournet et al 1999) and in predicting formation of small aromatic compounds for flame of methane (Gueniche et al 2009;Belmekki et al 2002).…”

Detailed kinetic study of anisole pyrolysis and oxidation to understand tar formation during biomass combustion and gasification

“…A new detailed kinetic model for the pyrolysis and combustion of anisole has been developed based on a recent model of ethylbenzene oxidation [32], which was used as a comprehensive reaction base for the reaction of aromatics and smaller species. This mechanism contains the different reaction pathways producing aromatic rings from lighter species, such as propargyl radical combinations and C4 and cyclopentadienyl reaction routes [33]. A submechanism for the reactions of anisole has been developed in the present work.…”

New experimental evidence and modeling study of the ethylbenzene oxidation

“…al [11]. This model includes a C 0 -C 2 reaction base, a mechanism to model the oxidation of C 3 -C 5 unsaturated hydrocarbons, especially allene, propyne, 1,3-butadiene and cyclopentene, as well as mechanisms for the oxidation of small aromatic compounds, benzene [12] and toluene [8].…”

“…al. [11] has been first checked for the consistency between kinetic and thermochemical data by calculating the reverse rate constant of every reaction and needed corrections have been made. Then a few updates of the reactions of the C 0 -C 6 species have been made (see Supplementary data).…”