Methanol synthesis from carbon dioxide (CO2) may contribute to carbon capture and utilization, energy fluctuation control and the availability of CO2-neutral fuels. However, methanol synthesis is challenging due to the stringent thermodynamics. Several catalysts mainly based on the carrier material Al2O3 have been investigated. Few results on MgO as carrier material have been published. The focus of this study is the carrier material MgO. The caustic properties of MgO depend on the caustification/sintering temperature. This paper presents the first results of the activity of a Cu/MgO catalyst for the low calcining temperature of 823 K. For the chosen calcining conditions, MgO is highly active with respect to its CO2 adsorption capacity. The Cu/MgO catalyst showed good catalytic activity in CO2 hydrogenation with a high selectivity for methanol. In repeated cycles of reactant consumption and product condensation followed by reactant re-dosing, an overall relative conversion of CO2 of 76% and an overall selectivity for methanol of 59% was obtained. The maximum selectivity for methanol in a single cycle was 88%.

Industrial CO2 emission mitigation necessitates holistic technology concepts; especially in high‐emission industrial sectors like the iron and steel industry. A novel direct reduction technology with hydrogen reduces CO2 emissions in iron production from siderite ore by more than 60 %. Subsequent valorization of the process gas, consisting of unconverted hydrogen, carbon monoxide, and CO2, by catalytic hydrogenation to methane and methanol completes the technology concept. This route gives access to CO2 emission‐lean iron production from siderite ore, fossil‐free methane and methanol synthesis, and thus, improved energy density of the energy carrier hydrogen.

Methane and methanol are promising products for CO2 hydrogenation for carbon capture and utilization concepts. In the search for effective, robust, easy-to-manufacture and stable catalysts, supported metal-based catalysts have proven advantageous. Whereas nickel for methane synthesis and copper for methanol synthesis stand out as efficient and cost-effective catalytically active metals, the best choice of support material is still a matter of ongoing debate. This review discusses the potential of the alkaline earth metal oxide MgO as support material for CO2 hydrogenation catalysts. Due to its basicity, it gives access to bifunctional catalysts as it shows pronounced CO2 adsorption capacity. Whereas carbonate formation seems to be beneficial in CO2 methanation, it may even have an adverse effect in methanol synthesis from CO2.

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