Magnesium as a Methanation Suppressor for Iron- and Cobalt-Based Oxide Catalysts during the Preferential Oxidation of Carbon Monoxide

The preferential oxidation of CO (CO-PrOx) to CO2 is an effective catalytic process for purifying the H2 utilized in proton-exchange membrane fuel cells power generation. Our current work reports on synthesis, characterization and CO-PrOx performance evaluation unsubstituted magnesium-substituted iron- cobalt-based oxide catalysts (i.e., Fe3O4, Co3O4, MgFe2O4 MgCo2O4). More specifically, ability Mg stabilize MgCo2O4 structures, as well suppress CH4 formation during was great importance this study. achieved higher yields than iron-based below 225 °C. highest yield (100%) over Co3O4 between 150 175 °C, however, undesired only observed catalyst due bulk fcc hcp Co0 200 250 presence suppressed formation, with reducing a CoO-type phase (possibly containing Mg). did not undergo reduction produce under reaction conditions. In conclusion, our study has demonstrated beneficial effect stabilizing active suppressing CO-PrOx.