SOLV-CFK
Chemical recycling of carbon-fiber reinforced plastic composites via solvolysis
Components made of carbon fiber-reinforced plastic composites are characterized by their high strength, durability, and low weight. However, their increased use in the automotive and aerospace industries, modern wind turbines, and other applications is leading to growing amounts of composite waste. A sustainable recycling process for the cost- and energy-intensive production of carbon fibers has not yet been established. As part of this project, a chemical recycling process based on solvolysis using sub- and supercritical water is being investigated. Water serves as a reaction partner to gently dissolve and recover the fiber-surrounding matrix, regardless of the epoxy used. The project focuses on optimizing process parameters such as pressure and temperature to enable efficient recycling with high fiber quality, as well as analyzing the resulting decomposition products.
Figure: Electrically heated high-pressure autoclave (process conditions up to 250 bar and 430 °C) for solvolysis (left) and recycled carbon fibers (right)
Contact Person: Dipl.-Ing. Konstantin Höfs
Project Start: 11/2023
Funding: Budget funds
Publications:
Konstantin Höfs, Emma Torre, Narender Katta, Andreas Hiller, Paul Schulz, Robert Kupfer, Nils Modler, Markus Schubert. Influence of Solvolysis Conditions on Recycling Products of CFRP Matrices. DECHEMA Jahrestreffen 2025 – Fachgruppe Abfallbehandlung und Wertstoffrückgewinnung (AuW), Hochtemperaturtechnik (HT) und Rohstoffe (ROH), Dresden, March 2025.
Höfs, K., Schubert, M. (2024). Determination of decomposition rates of epoxy resins for carbon fiber reinforced composites with sub- and supercritical water based on a shrinking core model. 16th International Conference on Gas–Liquid and Gas–Liquid–Solid Reactor Engineering (GLS-16), Dresden September 2024.
Schubert, M., Hiller, A. (2023). Solvolysis - a suitable approach to recycle fiber composites? 26th International Dresden Lightweight Engineering Symposium, Dresden, June 2023.
Maisels, A.; Hiller, A.; Simon, F.-G.: Chemisches Recycling für Kunststoffe: Status und Perspektiven. In: Chem. Ing. Tech. 2021, 93, No. 11, 1-10.