Removal Dynamics of Nitric Oxide (NO) Pollutant Gas by Pulse-Discharged Plasma Technique

Nonthermal plasma technique has drawn extensive attentions for removal of air pollutants such as NO(x) and SO(2). The NO removal mechanism in pulse discharged plasma is discussed in this paper. Emission spectra diagnosis indicates that the higher the discharge voltage is, the more the NO are removed and transformed into O, N, N(2), NO(2), and so forth. Plasma electron temperature T (e) is ranged from 6400 K at 2.4 kV discharge voltage to 9500 K at 4.8 kV. After establishing a zero-dimensional chemical reaction kinetic model, the major reaction paths are clarified as the electron collision dissociation of NO into N and O during discharge and followed by single substitution of N on NO to form N(2) during and after discharge, compared with the small fraction of NO(2) formed by oxidizing NO. The reaction directions can be adjusted by N(2) additive, and the optimal N(2)/NO mixing ratio is 2 : 1. Such a ratio not only compensates the disadvantage of electron competitive consumption by the mixed N(2), but also heightens the total NO removal extent through accelerating the NO oxidization process.