Reaction of nitric oxide with metal-loaded carbon in the presence of oxygen

Abstract

The effective removal of a low concentration of nitric oxide can be realized by using carbon as a reducing agent. The C-NO reaction was catalyzed by metal loaded on coal-char both in the presence and in the absence of oxygen. This C-NO reaction was remarkably promoted by the presence of oxygen at temperatures as low as 300 °C. The ratio of the activity for NO_x, decomposition to that for carbon combustion in the coexistence of nitric oxide and oxygen depended on the kind of metal catalyst. The order of catalytic activity was Cu > Ca > Ni > none for the C-NO reaction, but Ca > Cu > Ni > none for the C-O₂ reaction. This result suggests a possible means of finding a suitable metal catalyst which can strongly promote only the C-NO reaction. A high conversion for the C-NO reaction in the presence of oxygen was achieved by copper-loaded brown coal-char.