One of the most important raw materials in the chemical industry, methanol is one of the world’s most manufactured chemicals. Methanol synthesis using recycled CO2 and sustainably generated H2 has already been successfully demonstrated in the MefCO2 (Methanol fuel from CO2) project at the Niederaussem Innovation Centre, for example. The scientists and engineers in the European research project LOTER.CO2M then aimed to make the process to manufacture methanol from CO2 and renewable electricity easier and more efficient.
Whereas this previously required a separate process of water electrolysis to generate hydrogen and a synthesis plant operating with high temperatures and pressures, the LOTER.CO2M project created the methanol directly by electrochemical means, at almost atmospheric pressures and temperatures of about 100°C. With DLR (Deutsches Luft- und Raumfahrtzentrum e.V.) as lead partner, nine companies and research institutes from six countries worked together to achieve co-electrolysis of fuels with carbon content – essentially alcohols such as methanol – from CO2 and water.
The project started in January 2018 and ended after testing the new technology in Niederaußem in March 2022. The findings of the project directly went into the subsequent project ECO2FUEL.
Project implementation
The electrochemical conversion of methanol into CO2 and water with the release of electrical energy has been known for a long time and is designated as a direct methanol fuel cell. This process is reversed in the LOTER.CO2M project: CO2 and water react in a special electrolyser to form methanol and other carbon-based fuels as soon as electric power is applied.
The acronym “LOTER.CO2M” stands for the cumbersome project title “CRM1-free Low Temperature Electrochemical Reduction of CO2 to Methanol”. From the beginning of the development process, attention has been paid to sustainability and protection of resources, by avoiding the use of critical raw materials such as rare earths (e.g. cerium and yttrium) and metals in the platinum group (e.g. palladium and rhodium), even though they are effective as catalysts.
Key tasks in the project involve the manufacture of suitable catalysts to provide an electrochemical reaction at the electrodes, the selection of an electrolyte (acid or alkaline), and the provision and removal of reactants and products via gas-permeable distributors and collectors.
At the end of development, the result is an electrolyser stack of about 30 cells with an active surface of about 100 cm2 per cell. Its electric output will be about 2-3 kW, enough to generate about ten litres of methanol or other carbon-based fuels from CO2 and water. The electrolyser and all its ancillary units are fitted in a standard commercial 20’ container and assembled at the Niederaussem Innovation Centre, where it then recycles CO2 from the pilot CO2 scrubbing plant located there.
1 CRM = critical raw materials
