INTERACTION OF OXYGEN AND CH4 WITH MOLYBDENUM OXIDE CATALYSTS

The Near-Edge X-ray Absorption Fine Structure (NEXAFS) technique and D ifferential Scanning Calorimetry (DSC) were utilized to investigate th e reaction of CH4 and O-2 on the MoO3/SiO2 catalyst. The NEXAFS result s showed that the stoichiometry of the molybdenum oxide catalyst suppo rted on silica was MoO3. MoO3 was reduced to MoO2 when the catalyst wa s exposed to CH4 at 773 K. NEXAFS results confirm that lattice oxygen is directly related to the process of CH4 oxidation which takes place on the surface of MoO3/SiO2 catalysts. DSC results show that the struc ture of MoO3 changes around 573 K and this structural change seems to improve the migration of oxygen in the lattice.