Kinetics of ion formation in the volumetric reaction of methane with air

The formation of ions in the volumetric reaction of methane and hydrogen with air is analyzed. In methane–air mixtures, the highest concentrations are observed for NO$^+$, NO$_3^-$, CO$_3^-$, CO$_4^-$, OH$^-$, NO$_2^-$ ions. In hydrogen–air mixtures, maximum concentrations are characteristic for NO$^+$, OH$^-$, H$_3$O$^+$, O$^-$, and O$_2^-$ ions. In both rich and lean mixtures after ignition there is a long time interval during which the ion concentrations are far from equilibrium. The duration of this interval and the ion concentrations in it depend on the initial parameters of the mixture and the air–fuel ratio.