Dynamic CO2 methanation using coprecipitated Mg(Ni)O-supported Ni catalysts

The high demand for robust, cheap and efficient CO2 methanation catalysts is constantly growing as the challenges are evolving and industrial relevance is increasing. In this work, a series of nanoscale nickel–magnesium oxide (NM) catalysts derived from a coprecipitated bimetallic single source precursor was compared to a commercial Ni/Al2O3 catalyst and an impregnated benchmark Ni/MgO catalyst. At 260 °C and 20 bar under steady-state conditions the best performing catalyst with a nominal molar nickel-to-magnesium ratio of 50: 50 reached 92% CO2 conversion with a CH4 selectivity close to 100% under stoichiometric conditions. This catalyst was then subjected to a range of temperatures, GHSVs and gas feed compositions for a 100 h time-on-stream resilience test showing no deactivation while effectively suppressing the competing RWGS reaction. The results suggest that coprecipitated NM catalysts are highly productive and stable surpassing industrial methanation Ni/Al2O3 catalysts in terms of activity, selectivity and GHSV endurance even under hydrogen deficient conditions.