REACTION-MECHANISM FOR AROMATICS FORMATION IN A LOW-PRESSURE, PREMIXED ACETYLENE-OXYGENE ARGON FLAME

This paper is aimed at validating a detailed reaction mechanism for th e formation of the first aromatic rings (benzene and phenyl radical) i n a rich premixed acetylene-oxygen-argon flame. Validation has been ca rried out by confrontation of computed mole fraction profiles of stabl e and labile species against experimental results. With only specific changes in kinetic data of a few reactions a good agreement was obtain ed for the mole fraction profiles of C-4 species. Distinction between singlet and triplet methylene radical was a more profound change broug ht to the mechanism and needed to obtain a good modelling of C3H3. The se changes result in a marked improvement in the modelling of C4H2, C4 H3, C4H4, C4H5, C3H3, C3H4 and C6H6, accompanied by a better coherence of the mechanism with recent kinetic data measurements. Pathways anal yses of benzene formation show that acetylene addition to C4H5 takes p lace close to the burner and is rapidly superseded by addition of prop argyl radicals to allene.