Halogen cycles as important contribution for stabilising the electricity grid and for de-fossilisation of a future industrial society
Organic halogenated compounds and polymers feature unique properties. They are key components for many modern technologies. However, these compounds are environmentally problematic, and their recycling is often based on high-temperature total oxidation by combustion. This leads to high energy consumption, release of large amounts of CO2, and loss of the underlying carbon skeleton. Halocycles targets a disruptive paradigm, that is the use of electrochemical processes to split the carbon-halogen bonds and recover the halogens as anions as well as the intact carbon skeleton as building blocks for a circular economy based around halogenated compounds. Halocycles targets electrosynthetic approaches capable of operating with intermittent electricity supplies, so that excess electricity produced from sun or wind power can be utilised to drive these processes.
Many of these highly halogenated compounds are widely used due to their outstanding stability. In particular, the use and sensible recycling of polychlorinated compounds such as PVC or lindane waste represent a central challenge, the electrochemical conversion also enables a dioxin-free route.
The electro-conversion of highly fluorinated residual streams (Teflon, PFA, etc.) will pose the greatest challenge, as it is necessary to work at strongly negative electrical potentials. For later applicability requires not only robust electro-conversion but also suitable processes, analysis, and purification of the potentially complex mixtures.
When converting highly halogenated compounds, toxicological consideration is essential. Furthermore, both the flexible electrochemical stage and the process engineering steps will be analysed in terms of materials and economics to assess the contribution to a possible halogen circular economy. Here, we expect that realising the goals of Halocycles will not only increase resource efficiency, but also open up further opportunities for raw material sovereignty, which has far-reaching implications for value creation from residual material streams and pave a path to a circular halogen economy.
Funded by
Halocycles aims at developing disruptive concepts for a circular economy revolving around halogenated organic compounds. To achieve these ambitious goals, Halocycles brings together a diverse group of researchers with expertise spanning from materials design and organic electrosynthesis to inorganic and macromolecular chemistry, analytics, toxicology, chemical engineering, and economics. Our team is centred in Rhineland-Palatinate with major hubs at Mainz (Johannes Gutenberg University and Max Planck Institute for Polymer Research) as well as Kaiserslautern (RPTU and Leibniz-Institute for Composite materials). Halocycles will collaborate with industrial partners who bring additional expertise and economic interests to the field of electrosynthetic dehalogenation chemistry.
In the fields of materials design and materials chemistry, Halocycles will develop new classes of electrodes and electrode modification which are suitable to catalyse selective dehalogenation reactions while withstanding the harsh conditions expected during these processes.
In the fields of organic electrosynthesis and electrocatalysis, Halocycles will develop new approaches to combine electrodes, redox mediators, and reactors to allow the batch or continuously operated dehalogenated of industrially important halogenated compounds.
Novel analytical tools using machine learning algorithms will be employed to interpret spectroscopic data from complex feed-streams or product mixtures.
Halocycles will utilise advanced concepts from chemical engineering to design pilot reactors to facilitate upscaling of the most promising processes developed.
Delhalogenated product streams generated in Halocycles will be studied for further upcycling and use in industrially relevant processes.
Toxicological analyses of important intermediates or products will allow assessment of possible fields of usage or limitations of use.
Energetic and economic considerations relating to the use of the processes developed to buffer fluctuations in the electricity grid will be undertaken.
In sum, Halocycles will bring together expertise in natural sciences, engineering, and economics to provide new answers on how to deal with persistent halogenated organic compounds leading up to a circular economic model for these important industrial materials. Halocycles will establish means for efficient use of feedstocks with recycling and upcycling, so that CO2-neutral processing of halogenated compounds becomes possible.
1st Symposium from 11. to 12. April 2024
Held at Johannes Gutenberg University Mainz
April 2023
The projekt started
November 2022
Sustainable recycling using electrochemistry:
Carl Zeiss Foundation supports new research project
HALOCYLCES
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- Specht, T., Arweiler, J., Stüber, J., Münnemann, K., Hasse, H., Jirasek, F. (2024): Automated nuclear magnetic resonance fingerprinting of mixtures, Magnetic Resonance in Chemistry 62, 286-297. DOI: 10.1002/mrc.5381
- Gupta, N., Serge, C., Nickel, C., Streb, C., Gao, D., Glusac, K. (2024): Catalytic Water Electrolysis by Co-Cu-W Mixed Metal Oxides: Insights from X-ray Absorption Spectroelectrochemistry, ACS Applied Materials & Interfaces 16, 35793-35804. DOI:10.1021/acsami.4c06365
- Mohazzab, B. F., Torabi, K., Gao, D. (2024): Design of nanostructured 2D (photo-)electrocatalysts for biomass valorization coupled with H2 production, Sustainable Energy & Fuels 8, 5620-5637. DOI: 10.1039/d4se01034e
- Zhao, Y., Chen, Z., Ma, N., Cheng, W., Zhang, D., Cao, K., Feng, F., Gao, D., Liu, R., Li, S., Streb, C. (preprint): Atomically Engineered WOx/MoOx-Modified Defect-Rich Pd Metallene for Enhanced Alkaline Oxygen Reduction Electrocatalysis, ChemRxiv. DOI: 10.26434/chemrxiv-2024-fkr00
- Müller, S., Ströfer, E., Kohns, M., Münnemann, K., von Harbou, E., Hasse, H. (2024): Conversions and Selectivities in Cold Plasma Partial Oxidation of Methane, Plasma Processes and Polymers e2400027, 1-13. DOI: 10.1002/ppap.202400027
- Specht, T., Arweiler, J., Stüber, J., Münnemann, K., Hasse, H., Jirasek, F. (2024): Automated Nuclear Magnetic Resonance Fingerprinting of Mixtures, Magnetic Resonance in Chemistry 62, 286-297. DOI: 10.1002/mrc.5381