Nitric Oxide Formation from Fuel Nitrogen Studied with a Pulse-Flame Combustor

Abstract

About 5 vol.% of aniline, pyrrole, cyclohexylamine, piperidine, pyridine, pyrrolidine or n-hexylamine were used as additives in isooctane to evaluate the effect of different nitrogen bonds in fuel molecules on the formation of NO in a laboratory combustor. All of these additives increased the NO concentration substantially over that resulting from isooctane alone. Under identical experimental conditions most of the additives produced essentially the same NO concentration, with the exception of aniline and pyrrole, which increased NO to a lesser extent. The influence of N₂ on NO formation was studied by comparing nitrogen and argon as a carrier gas under rich and lean conditions. The smallest contribution of fuel nitrogen to the NO formation was measured in N₂ under oxidizing conditions.