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

Abstract

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 × 10−11 to 5.9 × 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 N2 at (275 and 350) °C. Fe2O3 and Co3O4 have the advantages such as facile synthesis, low-cost, good thermal stability, high activity and selective to N2. 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.