CO2 methanation catalyzed by a Fe-Co/Al2O3 catalyst

Abstract Carbon dioxide (CO2) hydrogenation to methanation is a potential way for alleviating greenhouse effect and storing energy sources. Here, alumina supported Fe-Co catalysts were synthesized and used for the CO2 methanation. Comparing with supported Fe/Al2O3 or Co/Al2O3 catalysts, the Fe-Co/Al2O3 catalysts showed superior catalytic performance under mild reaction conditions (280 °C and 0.2 MPa), whose reaction rate was 8.7 μmol·gcat−1·s−1. It was 3 times higher than that of 2.4 μmol·gcat−1·s−1 for the Fe/Al2O3 catalysts and 2.8 μmol·gcat−1·s−1 for the Co/Al2O3 catalysts. Based on the comprehensive investigations by the temperature-programmed reduction by hydrogenation (H2-TPR), in situ X-ray diffraction (XRD) and catalytic test in different integration manner of catalysts, the cooperative effect between Fe and Co was determined in the Fe-Co/Al2O3 catalyst. The presence of Fe effectively reduced the working pressure of the reaction and the Co directly acted on the CO2 conversion and CH4 formation. When compared to Fe/Al2O3 or Co/Al2O3 catalysts, the reducibility of metals and adsorption capacity for CO2 and H2 promoted a lot in the Fe-Co/Al2O3 catalyst, leading to the enhanced reactivity for CO2 methanation.