Beschreibung
Multi-material materials are challenging waste fractions for mechanical recycling processes. One example of these waste streams are expired but unused Filtering Face Piece (FFP) masks that are commonly disposed of through incineration, despite being biologically uncontaminated. This study investigates the technical feasibility and environmental performance of mechanically recycling FFP3 masks. A mechanical recycling approach was developed, that consists of pre-shredding, shredding, pelletising and extrusion. The resulting polypropylene recyclate was compared to commercially available recyclates based on the melt flow rate and mechanical properties: tensile strength, tensile modulus and impact strength. The recycled material exhibits suitable melt flow rates and comparable or higher mechanical properties. In addition, a life cycle assessment (LCA) was performed to compare the potential environmental impacts of developed recycling approach with the current waste treatment, incineration with energy recovery. While incineration shows lower net impacts due to energy credits, mechanical recycling can achieve net-negative environmental impacts when the recyclate substitutes virgin polypropylene in appropriate product applications. The results demonstrate the technical and environmental potential of mechanically recycling expired FFP3 masks, while highlighting limitations related to mask design variability, data availability for the environmental assessment, and transferability to other mask types.