Oxidation of methane over polyoxide catalysts

Abstract

The effect of modifying additives of copper, neodymium and molybdenum on acidity and dispersity of nickel catalyst is studied by temperature-programmed desorption of ammonia and scanning electron microscopy. The activity of these catalysts in the reaction of partial oxidation of methane (POM) and dry reforming of methane (DRM) are measured. The greatest activity is observed for the catalysts NiCuNdMo/Al2O3HZSM-5. The introduction of molybdenum into the NiCuNd/Al2O3HZSM-5 catalyst increases the total acidity of the catalyst from 26.71 × 10−4 to 29.46 × 10−4 mol/gKt, and also it increases the dispersion of the active phases of the catalysts surface. This data of change positively affects the activity of the catalyst in POM reaction, concentration of hydrogen in the reaction product compared with NiCuNd/Al2O3HZSM-5 increases from 60 to 70 vol %. In the range 650–900 °C the equilibrium yield of H2 and CO is observed in the conversion of methane by carbon dioxide over the NiCuNdMo/Al2O3HZSM-5 catalyst. In the oxidation of methane by oxygen the main products is hydrogen, whereas synthesis gas is formed in the conversion of methane by carbon dioxide.