Karlsruhe Institute of Technology Launches Research on Producing Carbon Black from Atmospheric CO2

At Karlsruhe Institute of Technology (KIT), the NECOC research project aims to build a unique test facility for the active reduction of atmospheric carbon dioxide (CO2). The world's first container-scale facility of this type will convert CO2 from ambient air into highly pure carbon black powder that can be used as a resource in industry. Project partners are INERATEC GmbH, a spin-off of KIT, and Climeworks, a spin-off of ETH Zurich. The research project, planned for a three-year period, is being funded with a total of EUR 1.5 million by the Federal Ministry for Economic Affairs and Energy (Bundesministerium für Wirtschaft und Energie). With the 2015 Paris Climate Agreement, the global community committed to limiting global warming to below 2°C by the end of the century. However, to achieve this goal, global efforts to reduce greenhouse gas emissions will need to be complemented by solutions to remove CO2 already released into the atmosphere. Thomas Wetzel, Professor at the Institute for Thermal Process Engineering (TVT) and Director of the Karlsruhe Liquid Metal Laboratory KALLA at the Institute for Thermal Energy Technology, said: "Our project approach consists of removing CO2 from the atmosphere and converting it into carbon black, meaning high-purity carbon in powder form. In this way, a hazardous greenhouse gas is converted into a raw material for high-technology applications. Carbon black can be used in electronics, printing or construction."

Test Facility Combines Several Process Steps

The test facility to be built as part of the NECOC research project will combine the following process steps: First, CO2 is captured from ambient air using an adsorbent (direct air capture, DAC). Together with renewable hydrogen, it is converted into methane and water in a micro-structured reactor. The produced methane serves as a carbon carrier in the downstream process and is fed into a bubble reactor filled with liquid metal. In the rising methane bubbles, a pyrolysis reaction occurs in which methane decomposes into its components. These are, on one hand, hydrogen which is recycled back to methanation and, on the other hand, solid carbon in microgranular powder form, namely carbon black. All process steps have been studied and developed to laboratory scale by the respective researchers. NECOC project coordinator Dr. Benjamin Dietrich (TVT) explained: "We know the individual modules well. However, they have never been implemented together in an integrated facility before. This is a world first. The skillful integration of process modules and correct process behavior will be decisive for the energy efficiency of the process and the quality of the carbon black product. Solid carbon is easier to store than CO2 and can even be used as a resource. So far, carbon black has been produced mainly from fossil oil. That is why our process represents a technological approach that is promising for a sustainable future from several perspectives. It combines direct contribution to solving the climate problem with a post-fossil resource supply process." The test facility will be built at KIT premises. The aim is to demonstrate the long-term results of operation. Future expansions of the facility are planned to increase performance per container and enable parallel operation of multiple facilities. KIT partners in the NECOC research project are the Karlsruhe Liquid Metal Laboratory (KALLA), the Institute for Thermal Energy Technology and Safety (ITES) and the Institute for Thermal Process Engineering (TVT). KIT will not only coordinate the project and operate the facility, but will also contribute to pyrolysis technology. NECOC will be funded by the Federal Ministry for Economic Affairs and Energy for three years with a total of EUR 1.5 million.