A comprehensive Analysis of Closed-Loop Food-Grade Polyolefin Packaging: Mechanical Recycling and Contaminant Assessment

The transition from a linear to circular economic model is essential to address the growing issue of value waste as a resource. This shift necessitates the development of efficient recycling processes to promote sustainability and circularity. This dissertation explores the role of mechanical recycling as a valuable asset in achieving circularity and sustainable development. The study highlights that while state-of-the-art technology enables effective material recovery from post-consumer plastic waste, it still faces challenges in producing high-quality recyclate suitable for closed-loop materials circulation and upcycling applications. To accelerate the development of decontamination processes, standardized and exhaustive tests for polyolefins are identified as crucial necessity. From a risk-based perspective, the research reveals that the tests conducted on food-contact polypropylene (PP) and polystyrene (PS) packaging samples yield results similar to those obtained from regular recycled polymer samples. No substances of very high concern (SVHC) compounds were detected. However, the detection of non-candidate compounds, such as 2-benzyloxyphenylacetic acid, calls for further investigation to identify the sources and mitigate potential health and safety concerns in the future. Notably, the exclusion of cosmetic- and personal care-related compounds, such as octocrylene, represents a significant improvement brought about by the selected material input addressing safety concerns upon exposure. The dissertation also emphasizes that, whereas current mechanical recycling methods are already capable of yielding high quality plastic materials, the HolyGrail 2.0 initiative is identified as a promising avenue for significantly improving material recovery and recirculation by preserving the physical chemical quality of recycled materials. This advancement is anticipated to expand the range of applications and make upcycling more accessible, further contributing to the promotion of a sustainable circular economy.