| Popis: |
In order to better understand the reaction pathway during the partial oxidation of methane, O-exchange with O 2 and CO 2 over V 2 O 5 /SiO 2 was examined using isotopic transient techniques. It was found that, during the partial oxidation reaction, the O-exchange capability of the V 2 O 5 /SiO 2 catalyst increased significantly. Secondary exchange reactions of CO 2 with the V 2 O 5 /SiO 2 were demonstrated. It was also shown that the CO 2 species exchanging with the catalyst were in equilibrium and that the rate of O-exchange with O 2 was much lower than with CO 2 . This resulted in an apparently higher contribution of lattice oxygen for O-exchange with CO 2 during the partial oxidation reaction. Thus, the identification of the origin of the O-species involved in the formation of a particular product is greatly complicated by the presence of secondary exchange reactions. |
