Collect. Czech. Chem. Commun. 1992, 57, 2529-2538

Mn-Mo-O Catalysts for Methanol Oxidation. I. Preparation and Characterization of the Catalysts

Krasimir Ivanova, Penka Litchevaa and Dimitar Klissurskib

a Department of Chemistry, Higher Institute of Agriculture, 4000 Plovdiv, Bulgaria
b Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, 1040 Sofia, Bulgaria


Mn-Mo-O catalysts with a different Mo/Mn ratio have been prepared by precipitation. The precipitate composition as a function of solution concentration and pH was studied by X-ray, IR, thermal and chemical methods. Formation of manganese molybdates with MnMoO4.1.5H2O, Mn3Mo3O12.2.5H2O, and Mn3Mo4O15.4H2O composition has been supposed. It is concluded that pure MnMoO4 may be obtained in both acid and alkaline media, the pH values depending on the concentration of the initial solutions. The maximum Mo/Mn ratio in the precipitates is 1.33. The formation of pure Mn3Mo4O15.4H2O is possible in weakly acidic media. This process is favoured by increasing the concentration of initial solutions.