Evonik and Siemens have launched a project called Rheticus, which plans to use electricity from renewable sources and bacteria to convert carbon dioxide (CO2) into specialty chemicals.

The two companies are working together on electrolysis and fermentation processes, an undertaking which is due to run for two years. The first test plant is scheduled to go on stream by 2021 at the Evonik facility in Marl, Germany which produces chemicals such as butanol and hexanol, both feedstocks for special plastics and food supplements, for example.

The next stage could see a plant with a production capacity of up to 20,000 tonnes a year. There is also potential to manufacture other specialty chemicals or fuels. Some 20 scientists from the two companies are involved in the project.

Dr. Günter Schmid, technical project responsible of Siemens Corporate Technology, explains, “We are developing a platform that will allow us to produce chemical products in a much more cost-effective and environmentally-friendly way than we do today.” He continued, “Using our platform, operators will in future be able to scale their plants to suit their needs.

The new technology combines multiple benefits. It not only enables chemicals to be produced sustainably, it also serves as an energy store, can respond to power fluctuations and help stabilise the grid.

Source: Evonik

Rheticus is linked to the Kopernikus Initiative for the energy transition in Germany which is seeking new solutions to restructure the energy system. The Rheticus project will receive €2.8m in funding from Germany’s Federal Ministry of Education and Research (BMBF).

Dr. Thomas Haas, who is responsible for the project in Evonik’s strategic research department Creavis, added, “With the Rheticus platform, we want to demonstrate that artificial photosynthesis is feasible.”

Artificial photosynthesis is where CO2 and water are converted into chemicals using a combination of chemical and biological steps, in a process similar to how leaves use chlorophyll and enzymes to synthesize glucose.

Siemens and Evonik are each contributing their own core competencies to this research collaboration. Siemens is providing the electrolysis technology, which is used in the first step to convert carbon dioxide and water into hydrogen (H2) and carbon monoxide (CO) using electricity. Evonik is contributing the fermentation process, converting gases containing CO into useful products by metabolic processes with the aid of special micro-organisms. In the Rheticus project, these two steps – electrolysis and fermentation – are scaled up from the laboratory and combined in a technical test facility.

Dr. Karl Eugen Hutmacher from the BMBF, said, “Rheticus brings together the expertise of Evonik and Siemens. This research project shows how we are applying the Power-to-X idea.”

Using electricity to generate chemicals is an idea from the Power-to-X concept. As one of the four pillars of the Kopernikus Initiative, the idea is to help convert and store renewable, electrical energy efficiently. At the same time, the Rheticus platform also contributes to the reduction of CO2 levels in the atmosphere, as it uses CO2 as a raw material. Three tonnes of CO2 would be needed to produce one tonne of butanol, for example.

Rheticus project: How to turn carbon dioxide into green chemicals