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Several ceria‐zirconia supported mono and bi‐metallic transition metal oxide clusters containing Fe, Cu, and Ni are synthesized by dry impregnation. Through XRD, H₂‐TPR, NH₃‐TPD, pyridine adsorption followed by FTIR spectroscopy and XAS, the well‐dispersed nature of the transition metal oxide clusters is revealed, and the Lewis acidity of the catalysts is assessed. In‐situ FTIR spectroscopy is used to monitor the methane activation on catalyst surfaces. All catalysts activate methane at 250 °C forming methyl, alkyl, and methoxy species on the catalyst surface. By co‐feeding steam and oxygen together with methane, continuous direct oxidation of methane to methanol can be achieved, with the complete oxidation to CO₂as the other reaction path. Methoxy species are found to be a key intermediate for methanol production. Lowering the methane conversion improves the methanol selectivity. By extrapolation, it is estimated that methanol selectivity close to unity can be achieved below a threshold of methane conversion at about 0.002 %. The formation of CuO and NiO mixed metal oxides produces stronger Lewis acid sites and yields higher methanol selectivity.

The reactions of acetone and hydroxyacetone over heteroatom doped BEA zeolites (Sn, Mo, and W) in the presence and absence of H₂O vapor are investigated using infrared spectroscopy. Acetone is converted to mesityl oxide over Sn‐BEA exclusively. At higher temperatures, larger oxygenates such as phorones, aromatics, and coke form. The presence of co‐adsorbed water in Sn‐BEA suppresses tautomerization. H₂O vapor is also beneficial for minimizing coke formation at high temperatures. Hydroxyacetone is converted into 2‐hydroxypropanal over Sn‐BEA, exhibiting high affinity to Sn sites up to 400 °C. Sn‐BEA catalyzes conversion of hydroxyacetone into the enol in the absence of H₂O, but exposure to H₂O induces the formation of 2‐hydroxypropanal and subsequent conversion to acrolein. The Lewis acid descriptors are used to rationalize the reaction pathways. For the isomerization of hydroxyacetone into 2‐hydroxypropanal, the hardness of acid sites influences the reaction and correlates with the overall Lewis acidity of the catalysts, respectively. However, the size of the exchanged metal significantly affects aldol condensation, where keto and enol forms of acetone adsorb to active sites simultaneously.