Catalytic reduction of NO with NH3 over carbons impregnated with Cu and Fe

Selective catalytic reduction (SCR) with NH3 remains as one of the most eff ective technologies controlling NO, emission from stationary sources. At lo w temperatures carbon exhibits higher catalytic activity in NOx reduction t han conventional catalysts made of metal oxides or zeolites. In,the present work, the rate of catalytic NOx reduction conducted at 110-200 degreesC ov er mineral matter free carbon particles was found to be low, contrary to th e findings reported in the literature. The activity of the carbon was signi ficantly enhanced from impregnating it with nitrates of Cu and Fe. The carb on impregnated with Cu shows the highest activity. The affinity of these ca rbon catalysts toward NH3 and NO, as well as the tendency of the impregnate d metal oxides toward reduction by carbon and H-2 has an order identical to that of their activity in NO reduction. The high activity of the metal-loa ded carbons was related to the combined catalytic effects of the carbon and the metal. It has been suggested on the basis of this study that the metal -carbon complexes may serve as the catalytic centers for oxygen transferenc e from NO to NH3, which is essentially slow in the absence of the metal.