MOSSBAUER STUDY OF PEROVSKITE OXIDES FOR OXIDATIVE COUPLING OF CH4 AND ABSORPTION OF CO2

Perovskite oxides, (Ba0.95Ca0.05)(Co1-xFex) O3-delta, are prominent ma terials for oxidative coupling of methane and for CO2 absorption at hi gh temperature, and these oxides before and after treatment in CH4 and CO2 atmosphere were analysed by Mossbauer spectroscopy. The perturbat ion of microstructure by substitution of Ha sites with Ca, and the ele ctron transfer of mixed valences in Fe and Co ions with the formation of oxygen vacancies at high temperatures, are considered to contribute strongly to the selectivity of CH4 coupling and the rapid absorption of CO2 at high temperatures.