The influence of NH3 on NO2 conversion in a dc corona discharge in N2:O2:CO2:NO2:NH3 mixture

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 N₂:O₂:CO₂: NO₂:NH₃ subjected to the so-called direct current (dc) corona discharge. The dc 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 dc 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.Supports from the Research and Development Commitee (KBN) under Programme KBN 0889/P4/93/04 and the Polish Academy of Sciences within IMP 3.1 project are gratefully acknowledged.