The reactions of nitromethane in the gas phase and on a Co-ZSM5 catalyst under the conditions of the methane /NO_x SCR reaction

The rate of reaction of nitromethane in the gas phase is little changed by the presence of O₂ or NO. The major products are CO, NO and H₂O, plus NO₂ if O₂ is included. The corresponding catalytic reaction over fresh Co-ZSM5 commences at a much lower temperature and gives primarily CO₂ and NH₃. the latter being oxidised to N₂ above 340°C. As the catalyst ages below 320°C HNCO eventually becomes the major nitrogen-containing product although it can be hydrolysed by added water. The results demonstrate one possible route for the methane-SCR reaction.