Comment on “high temperature shock tube study of the reactions CH 3 + OH → products and CH 3 OH + Ar → products”

In [1], experiments are performed on the title reactions to determine the rate coefficients for these reactions as a function of temperature. The authors’ result for the reaction CH3 + OH → products is very important to understanding the acetylene–methane chemistry in the postflame region of moderately rich ( = 1.5), atmospheric pressure, nonsooting, hydrocarbon– air flames [2]. Measured hydrocarbon species profiles in rich, laminar, flat flames fueled by methane, ethane, ethylene, or propane in [2] show that both acetylene and methane persist in the postflame gas to a distance greater than 1.0 cm beyond the flame front, which is located ∼0.15 cm above the burner. Acetylene is converted into methane in this region, resulting in rising methane concentrations as the distance from the flame front increases for all fuels except methane. The amount by which the product methane rises depends upon the fuel used. In the case of ethylene fuel over the distance range 0.6–1.3 cm above the burner, the acetylene mole fraction decreases from 2100 to 1300 ppm, while the methane mole fraction increases from 900 to 1200 ppm. Other hydrocarbon species measured in the