Carbon Dioxide Hydrogenation

The ecological impact of carbon dioxide (CO2) in the atmosphere necessitates a reduction of CO2 emissions and demands utilization strategies. Hydrogenation processes may contribute to reduction of CO2 emissions, and furthermore can be used in energy storage. The possible hydrogenation processes methanation and methanol (CH3OH) synthesis are investigated. Due to thermodynamic stability of CO2 large scale hydrogenation needs robust catalysts with sufficient activity at moderate reaction conditions, which are easy to prepare, easy to recycle, and stable for long term usage. Exemplarily, Ni doped MgO catalysts offer great performance in methanation and can easily be recycled in basic-oxygen-furnaces in either steel or copper industry.MoP3-(06) page 1MoP3-(06) page 4

Catalytic Hydrogenation of CO2 to Methanol over Cu/MgO Catalysts in a Semi-Continuous Reactor

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%