Surface Species Formed during Methane Oxidation over Some Rare Earth Elements Oxides

摘要

This study has compared the ability of paramagnetic element oxides i.e. Pr, Eu, Yb in catalyst oxidation of methane. These have been prepared by precipitation, and then calcined at 600°C to get M₂O₃. Methane was then passed through a disk in KBr, and the reactions were conducted at room temperature; 200 style="white-space:normal;">°C and then 300 style="white-space:normal;">°C. The reaction products were then identified by F.T.I.R spectroscopy. It was observed that these oxides have extracted the protons from methane and the CH₃ style="white-space:normal;">·radicals were evidently formed. This focused radical react further to give CH₃O, C₂H₆ and the formation of Propionic acid is reported as one of the catalytic reaction products. The study also indicated the presence of aromatic products and in some instances, phenol was identified. Thereafter, the mechanism of the reaction was envisaged. For all the catalysts the conversion increases relatively with increasing the reaction temperature. The study can deduce that these oxides have the same ability as those of high paramagnetic properties to extract the proton, but the products are trapped and react further on the surface of the oxide.