NOx production in plasma reactors by pulsed spark discharges

Nitrogen fertilizers are important for modern agriculture, among which nitric acid is a basic chemical for ammonium nitrate production. Herein, NOx was produced from N2 and O2 using a spark discharge technology with point-to-point and circle-to-plate types of plasma reactors driven by a nano-second pulsed power supply. NOx could be produced with an energy efficiency of 0.09 mol/kWh under the gases of 50%/50% N2/O2, while NO2 selectivity increased with increasing energy density. The gas temperatures in the spark channels were estimated using the Gibbs free energy equation. Based on kinetics calculations, the reactions of N with O2 and O with NO were the major reactions for NOx production.