Pilot plants: Process optimization up to the industrial prototype

At Fraunhofer IAP, we operate pilot plants for industry. They allow us to develop new technologies, materials and processes that advance society and the economy. Our pilot plants support industry in testing syntheses for polymers, biopolymers or nanoparticles, scaling up promising approaches to material and process development, and producing products on a cost-effective basis. These are crucial steps in making innovative laboratory-scale solutions fit for production and large-scale processing. After all, not everything that works in a test tube or on a small scale makes it to market maturity. This is how we pave the way for new technologies to enter the market and daily life.

At the Fraunhofer Pilot Plant Center PAZ in Schkopau, we operate Europe’s largest industrial-scale facility for polymer synthesis outside of industry. In September 2023, we opened a new, 550-square-meter building where we conduct sustainable polymer synthesis. Our aim is to use renewable raw materials and to increase the resource and energy efficiency of the plant and production processes. This also includes measures to reduce or even avoid the use of environmentally harmful solvents in syntheses.

Another focus is on the further development of innovative synthetic rubbers, such as the biomimetic synthetic rubber BISYKA. Vehicle tires made from BISYKA rubber cause around 30 percent less abrasion than tires made from natural rubber, thus reducing microplastics in the environment. The new building received around 7 million euros of funding from the European Union (ERDF), the Ministry of Science, Energy, Climate Protection and the Environment of the State of Saxony-Anhalt, and the Federal Ministry of Education and Research.

Bioplastics are increasingly becoming an alternative to petroleum-based plastics. These sustainable materials offer several advantages, for example, they are made from renewable raw materials and can be biodegradable. Biopolymers help to reduce dependence on fossil raw materials and greenhouse gas emissions. They have processing properties that are comparable to those of conventional plastics. In order to be able to achieve various industrial applications, we are expanding the range of products on offer. There is a great demand for development in this area.

Polybutylene succinate (PBS)

In the RUBIO project, 18 partners from industry and research are fulfilling the vision of a sustainable plastics economy. Researchers at Fraunhofer IAP are developing new types of the bioplastic polybutylene succinate so that it can be used for significantly more applications. Both the synthesis process for the new PBS types and the transfer of the results to an industrial pilot scale are carried out at Fraunhofer IAP. In addition, our experts at the Biopolymers Processing Technology Center Schwarzheide are investigating how the newly developed plastic types and mixtures can be thermoplastically processed – from blow molding to extrusion and injection molding. Tests on biodegradability, printability, sealability and machinability are also carried out at the processing technology center. PBS is produced from renewable sources and is biodegradable. In the RUBIO project, regional plant residues are to be used in future.

“In principle, all materials that contain cellulose or lignocellulose can be recycled. These include non-rotting fermentation residues from biogas plants, various forms of agricultural residues and, theoretically, even waste from paper production.”

Thomas Büsse, Coordinator of the RUBIO joint project “Processing”

Polylactic acid (PLA)

The bioplastic PLA, also known as polylactic acid or polylactide, is obtained from lactic acid and has a high market potential in the bioplastics sector. The biodegradable polymer is made from renewable raw materials such as corn starch or sugar cane. PLA is widely used as an environmentally friendly alternative to conventional plastics. The packaging industry manufactures carrier bags, cups, trays and films from polylactic acid. In the textile industry, it is used to produce clothing and nonwovens. Medical technology uses polylactide in absorbable suture materials or implants. It is also a popular material in 3D printing. A pilot plant is available at Fraunhofer IAP for the development of new PLA materials. It enables syntheses up to the kilogram scale, both in batch and continuous processes. We are commissioned by customers to test different qualities of lactic acid. We check whether the lactic acid can be produced into PLA, and we support the development process through to the production of stabilized PLA. We also improve synthesis processes and adapt the properties of PLA materials for specific applications.

Green plastics – bio-based polymer building blocks

In the “Green Plastics” project, a team of researchers from several Fraunhofer Institutes is investigating how polymers can be produced from carbon dioxide and biogenic raw materials. Headed up by Fraunhofer IAP, the scientists are developing the entire process chain for the production of sustainable polymers through fermentation – i.e. through microbial or enzymatic processes. From the cultivation of the microorganisms and their fermentation in bioreactors, to the purification of the target substances and the design of the reactors, the researchers are gathering data that will be used to develop sustainable processes for the chemical industry. “Green Plastics” is part of the Fraunhofer flagship project “ShaPID - Shaping the Future of Green Chemistry by Process Intensification and Digitalization.” With this flagship project, Fraunhofer-Gesellschaft is supporting the transformation of the chemical industry towards sustainable and environmentally friendly production – so-called green chemistry. Dr. Ulrich Wendler, head of the Synthesis and Product Development Department at Fraunhofer PAZ, a research division of Fraunhofer IAP, presented the initial findings from “Green Plastics” at the “Fraunhofer Technology Day - Scale up Green Chemistry Now!”, which was held on November 29, 2023.

Our many years of experience in polymer development are helping us strengthen the circular economy. Recycling is one important aspect of this. We use an industry-oriented pilot plant to investigate new methods of separating and processing materials. We test, analyze and evaluate recycling processes for petroleum-based and bio-based plastics – especially for polyamides and polyesters. We are also developing and testing processes to recover monomers from plastic products. In the circular economy, they can be reused as precursors for new, high-quality polymers.

“Chemical recycling is a growing field of research and development. One of the major challenges is to recover monomers that have a high degree of purity.”

Dr.-Ing. Marcus Vater, Head of the “Chemical and Biological Recycling” working group at Fraunhofer IAP. In the following interview, he talks about current developments and fields of activity.

At the Center for Applied Nanotechnology CAN, a research division of Fraunhofer IAP, we operate a flow reactor for the production and scaling of high-quality, metal-based nanoparticles. Metal-based nanomaterials are suitable for many applications. In fuel cells, for example, they serve as catalysts, in printable inks they can be processed into semiconductor layers for solar cells, in medicine they help to diagnose diseases. Our flow reactor allows us to quickly change synthesis parameters and thus significantly accelerate nanoparticle development time.

At Fraunhofer IAP, we have at our disposal various pilot plants in the Polymer Materials and Composites PYCO Research Division that are used in polymer-based lightweight construction with fiber-plastic composites. Their fields of application range from the development of special polymers or methods for curing composites to the production of entire components in lightweight construction. Among other things, industrial partners have access to a modular impregnation system that can be used together with a large-scale continuous microwave to tests strips of materials. We use a second large-scale microwave to test curing processes for carbon fiber-reinforced components up to one meter in width and height.

We produce fiber composite components with complex geometries using automated fiber placement technology (AFP technology). It enables the precise and efficient production of fiber composite components for industries that place high demands on the strength and rigidity of components, such as the aerospace, energy technology and automotive industries. We are currently using AFP technology to develop a very lightweight drive and side shaft system for cars and trucks that has a thermoplastic matrix. According to our calculations, the fuel consumption of a vehicle with the new shafts can be reduced by 0.3 percent, thereby significantly lowering the CO₂ emissions of newly registered cars and trucks in Germany. A weight savings of more than 65 percent can even be achieved compared to steel drive shafts.