Dynamics of Methane Impurity Conversion in Glow Discharge in Helium

This paper presents the results of numerical calculations to study the dynamics of methane conversion in helium in a DC glow discharge plasma. Analysis of changes in the concentrations of neutral particles and radicals revealed that intense methane decomposition begins at 0.05 s, reaching a significant concentration reduction of five orders of magnitude by 3.5 s. During this interval, atomic hydrogen becomes the dominant impurity, with its concentration reaching a maximum between 0.5 and 20 s. It is shown that molecular carbon C2 and the CH radical reach their maximum concentrations at 0.5 s, which is important for the synthesis of carbon nanostructures.