Synthesis of NO by rotating sliding arc discharge reactor with conical-spiral electrodes

Nitrogen oxides (NOx) generated by discharge plasma with air have many application prospects in the fields of medicine, nitrogen fixation, energy and environmental protection. In this paper, high voltage AC power supply was used to excite cone-spiral electrodes to generate large area discharge, amount of gaseous NOx was generated, and then nitrogen dioxide (NO2) was converted to nitric oxide (NO) by a redox reactor molybdenum wire under high temperature conditions. The results show that the generations of NOx are affected by the applied discharge energies, frequencies and airflow states (1.31-2.62 m/s are the laminar flow, 2.62-5.24m/s are the transition state, 5.24- 6.55m /s are the turbulent flow). Moreover, the concentrations of NO, NO2 and NOx gradually increased, and the concentration ratios of NO/NO2 and NOx/NO2 decreased with increasing the discharge power from 104.2 J to 170.2 J. Meanwhile, the concentrations of NO, NO2 and NOx gradually decreased, and the concentration ratios of NO/NO2 and NOx/NO2 first decreased and then increased with increasing the applied frequency from 5.0 kHz to 9.0 kHz. Further, the concentrations of NO, NO2 and NOx gradually decreased, and the concentration ratios of NO/NO2 and NOx/NO2 first increased and then decreased with increasing the air flow speeds from 1.31 m/s to 6.55 m/s. Additionally, the concentrations of NO gradually increased while the concentration of NO2 gradually decreased and the concentration unchanged basically by adjusting the temperature of the high-temperature molybdenum converted reaction device from 25 ℃ to 350 ℃. This research can provide experimental support for the application of plasma in the fields of medicine, nitrogen fixation, energy and environmental protection.