Selective catalytic reduction of NO with CO using different metal-oxides incorporated in MCM-41

• Metal-oxide catalysts activity correlated with their M–O bond-strength.
• The catalyst ability to release lattice oxygen initiates reaction between NO and CO.
• Ru-MCM-41 is the most efficient catalyst with lowest reaction onset temperature.

Metal oxide doped mesoporous silica (MCM-41) were prepared by a co-precipitation method and utilized for the selective catalytic reduction of nitric oxide with carbon monoxide at temperatures in the range 423–723 K. The supported metal oxides investigated included oxides of ruthenium, copper, cobalt, nickel and iron. This selection offered a wide range of metal–oxygen bond strength within the catalyst. The catalysts were characterized by powder XRD, N2 sorption analysis and temperature programmed reduction (TPR) in hydrogen. At reaction temperatures less than 550 K the activity of the catalysts was in the order of Ru-MCM-41 > Co-MCM-41 > Ni-MCM-41 ≈ Fe-MCM-41 ≈ Cu-MCM-41. At reaction temperatures above 650 K, the Ru-MCM-41 was still the most active catalyst followed by Cu-MCM-41.