The interaction of NO with active carbons promoted with transition metal oxides (Mn, Cr, Co, Ni) was studied. Activity in reduction by carbon increased from ca. 573-653 K in comparison to unpromoted active carbon. The extent of increase in activity, as well as selectivity to N-2, depended on the type of active material. Product distribution (N-2, N2O) showed similarities with SCR by ammonia which suggests that some steps are in common for both reactions. TPD experiments indicate that undissociated NO molecule adsorbed on the surface may be the source of N2O, (C) 2004 Elsevier B.V. All rights reserved.