Effects of CO and H2 on the formation of N2O via catalytic NO reduction

The formation of N2O in a mixture of NO, CO, H2, O2 and N2 was investigated experimentally in a tubular-flow reactor containing a catalyst. It was found that the reduction of NO is enhanced by the presences of H2, and to a lesser extent CO, and that N2O is formed as a by-product of NH3 decomposition and NO reduction in the presence of H2, and through NO reduction in the presence of CO. The main product of NH3 oxidation is N2 in addition to the products of NO and N2O, and the rate of conversion for NH3 to N2O is about 10%. The conversion of NO to N2O is higher in the presence of H2 than in the presence of CO at lower temperature, and there is a range of temperature in which the formation of N2O is enhanced in the presence of either H2 or CO, whereas CO enhances N2O production from catalytic NO reduction more than H2 in a CO/H2/NO/O2/N2 gas system.