Influence of the Method of Synthesis of Cerium Oxide and its Modification with Manganese Oxide on the Activity of Copper-Cerium Catalysts in the Reaction of Oxidation of CO to CO in a Mixture of CO + O + H

Cerium oxide was synthesized by pyrolysis of the salt Ce(NO) · 6HO (P), co-combustion of Ce(NO) · 6HO with urea (M), sol-gel method (Z-G) and decomposition of the hydroxide precipitated by mixing aqueous solutions of Ce(NO) · 6HO and ammonia (G). Samples with manganese oxide MnO/CeO and MnCeO were obtained by impregnation and using urea. The effect of specific surface area on the activity of CuO/CeO CuO/MnO/CeO CuO/MnCeO samples in the reaction of CO oxidation in a mixture of CO + O + H in the range of 30 – 400°C was studied. It was found that the supported catalysts nCuO/nMnO/CeO(P) (n = 5,7.5,10 wt%) provide the highest conversion of CO to CO compared to that in the presence of the systems (5 – 10)% MnO/CeO(P) MnCeO(M) (x = 0.1 – 0.5) 7.5% CuO/MnCeO. On nCuO/nMnO/CeO(P) samples, 100% conversion of CO to CO is achieved at 120°C, the temperature window ΔT, in which this value remains unchanged, is 40°C, which is worse than the values for (7.5 – 10)% CuO/CeO(P) catalysts, for which 100% conversion of CO to CO is recorded at 100°C and is maintained up to 160°C in the temperature window ΔT = 60°C. Based on X-ray diffraction (XRD) and temperature-programmed reduction with hydrogen (TPR H) data, it is concluded that oxygen from the interacting oxides MnO/MnO CeO in binary systems participates in CO oxidation. The introduction of copper oxide into them increases oxygen activity as a result of the formation of copper-manganese oxide structures in ternary systems.