Siemens Energy and Evonik commissioned a pilot plant sponsored by the German Federal Ministry of Education and Research (BMBF) that uses carbon dioxide and water to produce chemicals. The energy is supplied by electricity from renewable sources. The pilot plant is located in Marl, in the northern Ruhr area, and uses artificial photosynthesis. It is an essential part of the Rheticus I and II research projects, which are sponsored by the Federal Ministry of Education and Research (BMBF) with $6.3 million euros in funding.
The Rheticus research project is a spin-off of the Copernicus projects, one of the largest research initiatives of the German government on energy system transformation. Rheticus demonstrates how Power-to-X idea can be put into practice.
Artificial photosynthesis researchers at the Rheticus experimental facility looked to nature as a model. Just as plants use solar energy to produce sugar, for example, from carbon dioxide (CO2) and water in several steps, artificial photosynthesis uses renewable energies to produce valuable chemicals from CO2 and water through electrolysis with the help of bacteria. This type of artificial photosynthesis can serve as an energy store and thus help to close the carbon cycle and reduce carbon dioxide pollution in the atmosphere.
The pilot plant has started up in Marl, the largest Evonik site. It consists of a CO electrolyzer developed by Siemens Energy, a water electrolyzer and the bioreactor with Evonik's know-how. In the electrolyzers, carbon dioxide and water are converted into carbon monoxide (CO) and hydrogen (H2) with electricity in a first step. This synthesis gas is used by special microorganisms to produce specialty chemicals, initially for research purposes. These are starting materials for special plastics or food supplements, for example.
In the coming weeks, the composition of the synthesis gas and the interaction between electrolysis and fermentation will be optimized. In addition, a unit for processing the liquid from the bioreactor will be set up to obtain the pure chemicals.
After successful completion of the current Rheticus project phase (Rheticus II), Evonik and Siemens will have a platform technology that can produce energy-rich and valuable substances such as specialty chemicals or artificial fuels from CO2 - in a modular and flexible manner.
"Climate protection is not possible without chemistry, because our industry supplies and develops solutions for the energy turnaround. Research projects such as Rheticus are a motivation and innovation driver for a sustainable society," said Harald Schwager, Deputy Chairman of the Executive Board of Evonik in a press release. "Security of supply and reliability in political decisions set the framework in which new things are created.”
"Our goal is to use innovative technologies to enable new, more sustainable solutions. With our hydrogen and CO electrolysis, we are building a bridge from green electricity to sustainable material applications,” said Christian Bruch, CEO of Siemens Energy in a press release. “The close cooperation between politics, science and business partners, like Evonik, is an important step in this direction.”