MOF-derived ceria-zirconia supported Co3O4 catalysts with enhanced activity in CO2 methanation

Abstract

Recent research in catalyst development for CO2 methanation has been focussing on the design of nanostructures with high porosity and better redox properties. Herein, nanostructured Ce0.8Zr0.2O2 mixed oxide support was prepared by a metal organic framework (MOF)-template approach and its properties were well compared with a similar catalyst prepared by a conventional coprecipitation (CP) method. The MOF-template approach resulted in the production of a nanoporous Ce0.8Zr0.2O2 support with improved redox properties compared to the coprecipitated Ce0.8Zr0.2O2. The prepared support was then decorated with Co3O4 nanoparticles and tested in CO2 methanation reaction. At 320 °C, 1.5 MPa and GHSV = 15,000 mL g˗1 h˗1, the Co/Ce0.8Zr0.2O2 catalyst prepared by MOF-template method achieved far better CO2 conversion (81.2%) and improved CH4 selectivity (99%) than the catalyst prepared by CP method (48.7% CO2 conversion and 97% CH4 selectivity). The long-time presence of the MOF-derived Co/Ce0.8Zr0.2O2 catalyst on the stream proved its resistance towards sintering, which may be ascribed to the fine dispersion of Co3O4 nanoparticles as well as their excellent integration in the network of nanoporous Ce0.8Zr0.2O2.