Nitric oxide formation in an ammonia-doped methaneoxygen low pressure flame

Abstract

Mass spectrometry and absorption spectroscopy have been used to measure the concentration profiles of most of the species appearing in a slightly rich H 4 O 4 low pressure flame doped with NH 3. The mole flux profiles of these species and the net reaction rate profiles of the reactions producing NO or N 2 from NH 3 have been derived. The data lead to the following conclusions: 1. a. The reactions ▪ and ▪ are not in equilibrium if the JANAF value of ΔH f(NH) is used in the calculations. If the value of Kaskan and Nadler [1] is used, the last reactions appear to be equilibrated. 2. b. The HCNCN system is in partial pseudoequilibrium near the flame front. 3. c. The measured NO yield is in good agreement with De Soete's [2] empirical correlation. 4. d. In the flame zone NH 3 is transformed to HCN or N 2 by the reaction sequence ▪ but in the post flame zone, HCN and CN decay to NO or N 2 by ▪ The reactions involving N atoms are the most important paths, in good agreement with results published by Morley [3] and Haynes [4].