Dynamic CO 2 Methanation using coprecipitated Mg(Ni)O-supported Ni Catalysts

Abstract

The high demand for robust, cheap and efficient CO 2 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 catalysts derived from a coprecipitated bimetallic single source precursor was compared to a commercial Ni/Al 2 O 3 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% CO 2 conversion with a CH 4 selectivity close to 100% under stochiometric 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/Al 2 O 3 catalysts in terms of activity, selectivity and GHSV endurance even under hydrogen deficient conditions.