Nickel-magnesium-modified cenospheres for CO2 methanation

Coal combustion for power generation is a source of CO2 emission into the atmosphere. During that process, waste materials are formed such as cenospheres, which are a fraction of fly ashes. These cenospheres were applied as a catalyst support for the CO2 methanation reaction, which is a promising process for carbon dioxide utilization. Two series of catalysts were compared, a reference one based on the unmodified cenospheres, and a second based on the cenospheres modified by perforation. Nickel supported on Cenospheres nickel, or else nickel with MgeAl mixed oxides, were prepared by solution combustion synthesis. Perforated cenospheres supporting MgeAl mixed oxides led to a catalyst with significantly improved catalytic performance (88% at 300 degrees C) and selectivity to methane (>99% at 300 degrees C). In this work we evidence better development of the specific surface area, increased surface basicity, improved dispersion of nickel crystallites thanks to the presence of MgeAl and enlarged number of basic centers at the surface. (C) 2022 The Author(s). Published by Elsevier Ltd on behalf of Hydrogen Energy Publications LLC.