Polypropylene (PP) is a common material for single-use food packaging. However, there is currently a lack of systems, technologies, and approvals across Europe to use recycled PP (rPP) as a Food Contact Material (FCM) in a closed loop. Instead, rPP is exclusively used in non-food applications. In order to ensure recyclability in the longer term, the use of recyclates in food contact materials must also be made possible. This requires technical innovations, systemic adjustments and regulatory changes to be implemented.
The «FCMrPP» project investigates the feasibility of a closed PP loop in Switzerland. The aim is to develop a value chain for rPP that meets the high demands placed on the material in terms of food safety. A closed loop would not only conserve valuable resources and support net-zero targets, but also strengthen the resilience of the Swiss economy.
Sorting for high-quality recyclate
A central challenge is the sorting of PP packaging: It is necessary to sort packaging according to food/non-food applications and their original manufacturing technique – injection molding or thermoforming – in order to be able to produce a high-quality recyclate. Sorting according to the area of application is carried out using artificial intelligence and near-infrared spectroscopy. However, there is no established technology for sorting according to the manufacturing technique. High purities were achieved for the project through manual sorting. Further technological advances are needed for large-scale implementation.
Processing and further processing for closing the loop
Another important step is the processing of the flakes. In a pilot test at KATZ, 94% of the printing inks were successfully removed using a de-inking process based on the know-how of the BASF company Chemetall GmbH. To protect the material from degradation during further processing, an additive blend from BASF's IrgaCycle® range was added during re-granulation. Until March 2025, the recyclate will be tested for initial demo packaging made of rPP in industrial processes at Greiner Packaging AG, Säntis Packaging AG and Silac AG, and then the filling and sealing behavior of the recycled packaging will be tested at Emmi Schweiz AG.
A closed loop for polypropylene would be a milestone for the circular economy, conserving resources, relieving the burden on the environment and enabling a more sustainable future.
Read our findings and challenges in the current KunststoffXtra.