The Role of Carbonate Formation during CO2 Hydrogenation over MgO-Supported Catalysts: A Review on Methane and Methanol Synthesis

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.