Synthesis of nitrogen oxides NO$_x$ in atmospheric pressure discharge sustained in the flow of argon-air gas mixture by continuous electromagnetic radiation with frequency 263 GHz

The results of an experimental study of a plasma torch sustained at atmospheric pressure in a flow of argon–air gas mixture by continuous radiation of a gyrotron with a frequency of 263 GHz are presented. The discharge sustained inside a customised electrodynamic structure having the shape of a truncated cone absorbed up to 80% of the injected millimetre radiation power in some regimes. It is shown that in the realised plasma-chemical process the degree of oxygen conversion into nitrogen oxides (NO$_x$ ) can be up to 58 $\pm$ 4%.