GRAFCO₂: New graphene materials for the synthesis of methanol from CO₂ and H₂

Project Summary

In order to reduce greenhouse gas emissions into the atmosphere generated by human activity, several routes have been identified. In addition to increasing the percentage of renewable energy use, the European Union, in its 2050 Energy Roadmap, establishes that the capture and storage of CO₂ (Carbon Capture and Storage: CCS) will have to play a key role in the overall generation of energy from fossil fuels. If, in addition, we are able to take advantage of CO₂ (Carbon Capture and Use, CCU) and convert it into commercially useful products, we will make the process viable and more sustainable.

An alternative is to hydrogenate the CO₂ to synthesise methanol, which, thanks to its physicochemical properties, is an excellent energy vector. This means that it can store energy from, for example, excess production peaks of solar or wind installations, and transport it safely to the point of use, avoiding the need for new transport and storage infrastructure. In addition, methanol can be used as a transportation fuel, but its major contribution to reducing CO₂ is to convert it into other molecules with longer lifetimes, such as ethylene, which is used in the production of plastics.

The scientific challenge of methanol synthesis by this route is that CO₂ is a molecule that is difficult to activate and convert into other products, which requires high energy consumption. To reduce this consumption, it is necessary to find catalysts that facilitate the process under industrially viable conditions. These catalysts must also be highly selective to the product of interest, stable and, as far as possible, compatible with existing facilities.

Therefore, the project proposes the use of transition metal carbides supported on graphene materials. These materials are characterised by their low cost and large surface area, which means they have the potential to disperse the active phase into very small particles. In addition, modifications in the graphene structure are expected to facilitate the activation of CO₂ and its conversion to methanol.

Application:  Mainly, the project applies directly to refineries, power generation plants and other industries such as steel production, which will eventually have to offset the CO₂ emissions they generate. The possibility of using this CO₂ as an economical, safe and renewable source of carbon to obtain high value-added products is one way of making the process viable. Furthermore, methanol, as an energy carrier, can play a key role in the future of energy, where we will see more decentralised and multi-source power generation systems.