Karlsruhe Institute of Technology (KIT) (Karlsruhe, Germany) will serve as the host site for a test facility that would actively reduce atmospheric carbon dioxide (CO2) by converting it into a highly pure carbon black powder.
KIT’s partners in this NEgative Carbon DiOxide to Carbon (NECOC) research project include the Karlsruhe Liquid Metal Laboratory (KALLA) and the Institute of Thermal Processes Engineering (TVT). Other outside partners include INERATEC GmbH, a spinoff of KIT, and Climeworks, a spinoff of ETH Zürich.
‘Our project approach consists of removing CO2 from the atmosphere and converting it into carbon black, i.e., highly pure carbon in powder form,” says Prof. Thomas Wetzel of TVT and head of KALLA. “In this way, a hazardous greenhouse gas will be converted into a raw material for high-tech applications…[including] electronics, printing, or construction.”
The KIT test facility to be set up by the NECOC research project combine several process steps, all of which were studied and developed up to the laboratory scale by the researchers involved. These process steps are as follows:
- By means of an adsorber, CO2 is captured from ambient air through direct air capture (DAC).
- Together with renewable hydrogen, it is converted into methane and water in a microstructured reactor.
- The methane produced serves as a carbon carrier in the downstream process and is passed into a bubble reactor filled with liquid tin.
- In the ascending methane bubbles, a pyrolysis reaction takes place, by which means methane is decomposed into its constituents: hydrogen and solid carbon.
- The hydrogen is directly fed back to methanation, while the solid carbon assumes the form of microgranular powder.
“We know the individual modules well,” says Dr. Benjamin Dietrich of TVT and project coordinator of NECOC. “However, they have never been realized together in an integrated facility so far…Skillful integration of the process modules and correct process conduct will be decisive for the energy efficiency of the process and the quality of the carbon black product.”
The end product of carbon black offers one major advantage over other previous research projects to reduce atmospheric CO2. “So far, carbon black has been produced mainly from fossil petroleum,” notes Dietrich. “This is why our process represents a technological approach for a sustainable future in several respects. It combines the direct contribution to solving the climate problem with a process for post-fossil resource supply.”
The NECOC research project is scheduled to take three years and is funded by the Federal Ministry for Economic Affairs and Energy for €1.5 million ($1.65 million).
Source: Karlsruhe Institute of Technology, www.kit.edu/english.