Structure Study of a Cf2br2-inhibited Methane Flame. Effect of Cf2br2 on Composition, Net Reaction Rates, and Rate Coefficients.
The microstructures and a cf2br2-inhibited methane flame and its uninhibited analog have been determined using molecular beam-mass spectrometry. The slightly lean flames were stabilized on a cooled porous plug burner at reduced pressure. Composition profiles of stable, intermediate, and radical species and temperature profiles revealed the following inhibition effects; a shift of the primary reaction zone to higher temperatures, a higher maximum flame temperature, an increase in the ch3 concentration, and a reduction in the h2co, h, o, and oh concentrations. Kinetic analyses of the data yielded rate coefficients at flame temperatures for the reactions h + ch4 -> ch3 + h2, h + o2 -> oh + o, CO + oh -> co2 + h, and ch3 + o -> h2co + h. Cf2br2 is judged to decay by thermal decomposition and abstraction reactions.