CoCe composite catalyst for the CH4/CO2 reforming reaction: Synergistic effects between Co and Ce species

Abstract

The greenhouse gases CH4 and CO2 can be use as feedstock to prepare syngas (CO + H2) by CH4/CO2 reforming reaction, and the syngas can be used to produce high value-added chemicals through Fischer-Tropsch reaction. That is, the CH4/CO2 reforming reaction can provide an effective way to rationally use CO2 and CH4. The CoCe catalysts were prepared by impregnation method and grinding method, respectively, and the physicochemical properties were characterized by H2-TPR, XRD, BET, Quasi in-situ XPS and CO2-TPD. The synergistic effects between Co and Ce species can promote the CH4 and CO2 molecules to be continuously and rapidly activated, so that the CoCe catalysts exhibited good catalytic activity for the CH4/CO2 reforming reaction. The preparation methods can affect the dispersion of the Co species and the thermal stability of the oxygen vacancies on the CoCe catalysts to affect catalytic activity. The impregnation method is conducive to the Co species dissolving into the CeO2 lattice to form oxygen vacancies with high thermal stability, and the Co species on the CeO2 surface were in a highly dispersed state, which can provide more stable catalytic activity centers. Thus, the catalysts prepared by impregnation method displayed superior catalytic performances for CH4/CO2 reforming reaction. And the CH4 and CO2 conversions can reach 43.4% and 29.0% at the reaction temperature of 600 °C, respectively.