Evonik and Siemens have launched the second phase of their joint research project, Rheticus II, which aims to produce specialty chemicals from carbon dioxide (CO₂) and water, using renewable electricity and bacteria.

The project follows Rheticus I, under which the companies worked for two years to develop the basis for artificial photosynthesis using a bioreactor and electrolyzers. In the process, the electrolyzers convert CO₂ and water into carbon monoxide (CO) and hydrogen. Special microorganisms then convert the CO in the gases into chemicals.

Over the coming months, the partners will combine the two separate units into a test facility to be installed at Evonik’s site in Marl, Germany. In addition, they will build a unit to process the liquid from the bioreactor to obtain pure chemicals.

The facility, which will produce butanol and hexanol for research purposes, will start operating in early 2020. Evonik said these chemicals are used, for example, as starting products for specialty plastics and food supplements. It added, however, that other specialty chemicals are conceivable, depending on the bacterial strain and conditions.

“In the future, this platform could be installed anywhere CO₂ is available – for example, at power plants or biogas plants,” said Thomas Haas, responsible for the Rheticus project at Evonik.

Rheticus II will run until 2021 and receive funding of about €3.5 million from Germany’s Federal Ministry of Education and Research (BMBF).