In Situ FT-IR Study of O2, CO, CO2, CH4 and C2H4 Adsorption or Reaction on the La2O3MgO Catalyst

Publisher Summary Rare earth/alkaline earth metal binoxides have been found to be very active for oxidative coupling of methane. In these systems, the nature of the active oxygen species is still not clear and has aroused much speculation. Superoxide O 2 − was the most abundant species seen by X-ray photoelectron spectroscopy (XPS) for rare earth–alkaline earth metal composite oxide. The possibility of such a superoxide ion being involved in the oxidative coupling of methane has been raised by several authors. This chapter studies the adsorption and reaction of O 2 , CO, CO 2 , CH, and C 2 H 4 on the La 2 O 3 /MgO catalyst using in situ Fourier Transform Infrared (FT–IR) spectroscopy. In combination with the behavior of oxidative coupling of methane (OCM) over the La 2 O 3 /MgO, the nature of surface oxygen species is discussed.