Magnetic field stabilized atmospheric pressure plasma nitrogen fixation: Effect of electric field and gas temperature

Abstract

In this paper, we investigate the influence of plasma characteristics on nitrogen fixation efficiency and explore the optimization of discharge parameters by utilizing a magnetic field stabilized atmospheric pressure plasma. The gas temperature and electric field of the plasma are maintained at a constant level and can be independently adjusted by controlling the discharge current, gas flow rate, and external magnetic field. The spatial distribution of the gas temperature of the plasma is measured by laser-induced Rayleigh scattering. The results show that reducing the electric field and gas temperature leads to an increase in NOx production. The optimal parameters for nitrogen fixation are identified as a discharge current of 55 mA, a gas flow rate of 6 l·min−1, and an O2 fraction of 40%. These settings result in the lowest recorded energy cost of 2.29 MJ·mol−1 and a NOx concentration of approximately 15 925 ppm. The stable characteristics of the magnetically stabilized atmospheric pressure plasma make it suitable for further investigations into the effect of plasma characteristics on nitrogen fixation.