The Influence of Cerium to Manganese Ratio and Preparation Method on the Activity of Ceria-Manganese Mixed Metal Oxide Catalysts for VOC Total Oxidation

A set of ceria-manganese mixed metal oxide catalysts with varying Ce:Mn ratios were prepared by coprecipitation using sodium carbonate and evaluated for the total oxidation propane naphthalene. Manganese-rich samples most active, Ce0.25Mn0.75Ox having highest activity. Catalysts characterised X-ray diffraction, Brunauer–Emmett–Teller (BET) surface area, Raman spectroscopy, temperature programmed reduction (TPR), electron microscopy, photoelectron spectroscopy (XPS), establishing that high activity was due to formation phase-separated Mn-substituted ceria Mn2O3 phases not simultaneously present in other catalysts. The catalyst preparation technique active ratio investigated co-precipitation urea, oxalic acid citric acid, mechanochemical grinding. For propane, urea more than coprecipitated catalyst, greater area increased phase separation. This work demonstrates oxides are parent oxide, but is also important controlling