The monooxides copper, manganese, molybdenum and chromium catalysts supported on MgF2 were tested in NO decomposition and reduction by propene. The effect of the oxides content, time on stream and O-2 concentration in reaction mixture during NO reduction on their catalytic activity was investigated. All the catalysts showed the optimum active phase concentration corresponding to 2-4 wt.% of the metal. For the best copper catalyst an effect of introduction of another oxide (manganese or chromium oxide) on the catalytic performance was studied. The double copper-manganese oxide sample containing 2 wt.% Cu and 4 wt.% Mn was proved to ensure the best catalytic performance. (c) 2006 Elsevier B.V. All rights reserved.