The influence of NH3 on NO2 conversion in a DC corona discharge in N-2:O-2:CO2:NO2:NH3 mixtures

The aim of this paper is to investigate the influence of NH3 additive (540-1470 ppm) on the conversion of NO2 and the creation of NO and N2O in a mixture of N-2:O-2:CO2:NO2:NH3 subjected to the so-called direct current (de) corona discharge. The de corona discharge was generated in a needle-to-plate reactor. Seven positively polarized needles were used as one electrode and a stainless steel plate as the other. The time-averaged discharge current was varied from 0 to 7 mA. It was found that the de corona discharge decomposed NO2 and produced NO and N2O. The reduction of NO2 was higher without NH3 additive if the residence time of the operating gas was relatively short. However, in a longer corona discharge processing the NH3 additive may be useful for reduction of NO2.