Redox reaction of nitric oxide and carbon monoxide over Fe2O3 and Co3O4 phases

Fe2O3 and Co3O4 phases are synthesized by the thermal treatment in an air-flow of hydrated salts based on Fe and Co. The materials are characterized by X-ray diffraction, energy dispersive spectroscopy, scanning electron microscopy, thermogravimetric analysis and surface area measurements. Fe2O3 and Co3O4 were tested for nitric oxide reduction with carbon monoxide in a 1:5 gas phase ratio and showed reaction rates in a range from 8.7 x 10(-11) to 5.9 x 10(-10) mol s(-1) g(-1) with an activation energy interval from 50.2 to 54.4 kJ mol(-1). Fe2O3 and Co3O4 achieved (100 and 98) % NO conversion with (96 and 80) % selectivity to N-2 at (275 and 350) A degrees C. Fe2O3 and Co3O4 have the advantages such as facile synthesis, low-cost, good thermal stability, high activity and selective to N-2. These results regarding activity and selectivity are better or similar to some catalysts based on noble metals (Rh, Pt and Pd) currently used for air pollutants control.