Fraunhofer Cluster of Excellence Circular Plastics Economy CCPELukas Killinger works in the Research Department “Advanced Recycling” at Fraunhofer CCPE. His work focuses on developing energy-efficient recycling processes for plastic waste, particularly depolymerization via solvolysis. He is currently evaluating and optimizing recycling strategies across the entire value chain to support industry partners in the transition to a sustainable and resource-efficient circular economy.
What do you work on at Fraunhofer CCPE? What creative ideas are you currently pursuing in your field of research?
In my research, I focus on the depolymerization of plastic waste using solvolysis. This process has the advantage that even mixed, contaminated waste can be recycled to a high standard. The end product consists of the basic building blocks (monomers) of the respective plastic, which can be easily purified and subsequently processed into plastics as good as new with high-quality properties. A major obstacle to the industrial application of this recycling strategy is often the high energy consumption. In my research, I therefore focus on making the processes more energy-efficient.
Do you have a specific project example, or why is this interesting for industry/society?
We humans produce a whole range of highly complex mixed waste streams, such as electronic scrap, textile waste, or automotive scrap. According to current state-of-the-art technology, this waste is predominantly thermally recycled. Higher-quality recycling methods are of interest for improved resource efficiency and a circular economy. In our projects, we specifically focus on these waste fractions to achieve improved value creation.
What has been your highlight so far at Fraunhofer CCPE?
A project from 2024 in which we were able to demonstrate the complete value chain for a waste fraction from the yellow bag. Through depolymerization, PET from this waste fraction was specifically broken down into monomers. These were purified, polymerized into virgin-quality PET, and finally processed into fibers. Various CCPE institutes collaborated on this project and were able to close the loop for this waste fraction together.
What challenges do you currently see for companies in the transition to a circular economy in the plastics sector (and how can Fraunhofer CCPE support companies in this process)?
Many companies are caught between the availability and costs of recycling processes on the one hand, and societal and legal demands regarding recycling rates on the other. With its extensive expertise in the circular economy, Fraunhofer CCPE offers the ability to compare, evaluate, and implement different recycling processes for a specific waste stream. This enables companies to identify an ideal recovery strategy for their waste that also meets societal and political requirements.
What does your typical workday look like?
My typical workday consists of a diverse mix of activities in the office and in the lab. This includes researching existing processes and framework conditions, developing new ideas at my desk—sometimes supported by numerical simulations—translating these ideas into the lab process, including a comprehensive analysis of the results, and finally scaling and evaluating the developed processes at a pilot plant scale. The variety of tasks is challenging on the one hand, but on the other hand, I really enjoy it and it rarely makes my daily work routine boring.