Study of High Temperature Gas Reaction of NO-CH-O2(-CO2) Mixtures By Means of a Molecular Beam Sampling-Mass Filter System

Abstract

The homogeneous gas phase reaction of NO-CH₄-O₂(-CO₂)-Ar mixtures in high temperature is investigated by means of the molecular beam sampling method. The reaction species NO, CH₄, HCN, CO, COk and N₂ are quantitatively analyzed with a mass filter system within a limit of 10 ppm. The species resulting from NO reduction are HCN, NH₃ and Na. The amount of HCN decreases with an increase in the ratio of O₂ to CH₄. Both NO reduction and formation of HCN, NH₃and N₂ are clearly enhanced by the addition of CO₂. Conversely, the consumption of O₂ is retarded. In these reactions, it appears that oxidation of CH₄ initiates the NO reduction and, therefore, HCN, NH₃ and N₂ are progressively formed. Based on the experimental results, an overall kinetic equation for HCN behavior associated to NO reduction is derived as follows: The effect of CO₂ addition on the present reactions is in agreement with a reaction mechanism proposed earlier by Haynes.