Flat flames of premixed acetylene-nitric oxide have been stabilized on a low-pressure burner, operating at 80 Torr, in the temperature range of 2800-3100K. Two flames were investigated, one fuel rich and the other of stoichiometric composition. Temperature profiles and concentration profiles of free radicals species and of the stable products of reaction were determined in the reaction and postreaction zones using spectroscopic techniques. NO, CN, NH, C2, CH, and OH were measured by absorption, CO2 and HEO were measured from the intensity of their infrared emission bands. The analysis of the data indicates that the reactions of NO with C2, CH, CN, and NH are extremely fast and are responsible for the majority of NO destruction in the early part of the flame. Later in the flame the reduction of NO continues, very likely, according to a Zeldovich reverse type mechanism.
I. INTRODUCTION
The high temperature chemistry of nitric oxide is a subject which continues to be of current interest. Referring to the early work of Wolfhard et al. [1-3] we believe that much about this chemistry can be learned by investigating nitric oxide flames. In continuations of the work of Wolfhard et al. the NHa-NO oxide flame was reinvestigated by Caralp et al. [4]. Using rapid scanning spectroscopy they identified excited species NHE, NH, OH, and NO emission spectra in the flame. They found that NO was reduced mainly by NH and NHE free radicals. In a recent study, Mainiero et al. [5] reinvestigated the HE-NO flames by emission and absorption spectroscopy. They measured O, OH, and NO concentration profiles in the reaction zone and were able to determine the rate constant of the H + NO reaction.
This research concentrates on the CEHE-NO oxide flame because of its important role in understanding the reaction of hydrocarbon free radicals with nitric oxide. The CEHE-NO flame