Promoting innovation for sustainable sorting and recycling of dedicated bio-based plastics

Project Information

PROSPER

Grant agreement ID: 101157907

DOI

10.3030/101157907

EC signature date 15 May 2024

Start date 1 September 2024

End date 31 August 2028

Funded under

• Food, Bioeconomy Natural Resources, Agriculture and Environment

Total cost

€ 10 196 836,25

EU contribution

€ 7 498 855,25

Coordinated by

UNIVERSITEIT GENT
Belgium

Periodic Reporting for period 1 - PROSPER (Promoting innovation for sustainable sorting and recycling of dedicated bio-based plastics)

Reporting period: 2024-09-01 to 2025-08-31

Summary of the context and overall objectives of the project

Plastics are part of our everyday lives, but most are made from fossil fuels and create serious environmental problems when plastic waste is not properly managed. Bioplastics, either made from renewable resources such as corn and/or degradable, offer a more sustainable alternative. However, their use is less than 1% of the plastic market due to technical, economic, and systemic barriers. Bioplastics are currently not sorted or recycled, limiting their potential to contribute to a truly circular economy.
This project aims to show that bioplastics can be collected, sorted, and recycled successfully and economically, creating a true circular system for these materials. Besides, the project works to develop a transparent and realistic extended producer responsibility (EPR) calculation scheme that will help turn these technical solutions into real-world practice.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

Waste characterisation campaigns were performed in three operating sorting plants (Italy, Spain, France) and three composting plants (France). Results provide valuable information about the bioplastic type and percentage within household packaging waste and biowaste among different countries. Large-scale sorting trials have been conducted, highlighting that bioplastic (both rigid and films) can be sorted out from mixed waste streams, by implementing dedicated near-infrared NIR optical sorter that is equipped with an extended NIR spectral library including bio-based plastics. Pre-treatment protocols have been developed to improve the purity of feedstock for further mechanical and chemical recycling. The first prototype was created via mechanical recycling using sorted and pre-treated PLA waste. Lab-scale depolymerisation and mechanical recycling of PLA and polyester blends were performed with high recycling yields. These demonstrate the technical feasibility of sorting and recycling bio-based plastics, and producing end products with similar quality. Additionally, a techno-economic assessment of PLA sorting has been conducted, with PLA sorting costs and break-even points examined under different market conditions. This was then submitted to a high-impact journal (Resources, Conservation and Recycling), and is currently in revision.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

Comprehensive characterisation of household packaging waste streams was completed across three demonstration sites in Spain (FCCMA), Italy (A2A), and France (SUEZ). The outcomes provide the first harmonised dataset on bio-based plastic prevalence at European scale. A NIR-based sorting program was developed, trained, and validated for the identification and separation of target bio-based plastics. The system was successfully tested on real Dutch municipal waste streams spiked with representative bio-based products (both films and rigids). This marks a significant advance beyond the state of the art, demonstrating reliable sorting of bioplastics within complex waste streams—an essential step towards closed-loop recycling of bio-based materials. Following initial sorting trials, pre-treatment protocol for bio-based plastics were established and validated to induce material loss and degradation but provide high-purity feedstock for downstream recycling. Lab-scale depolymerisation of PLA achieving high conversion efficiency and high purity of recovered monomers. In parallel, solvolysis process for polyester blends was advanced, with high recovery of bio-polyesters achieved even in the presence of 5–10% fossil-based contaminants. These breakthroughs extend the applicability of chemical recycling to complex, mixed waste streams and blended bio/fossil polymers—currently a key limitation in the field.
Furthermore, mechanical recyclability of PLA and BIOTEC blends through multiple extrusion–thermoforming cycles was demonstrated, maintaining acceptable mechanical properties after three recycling iterations. Complementary solid-state post-condensation (SSPC) trials indicated the potential for molecular weight recovery, thus enhancing material performance and extending product lifetimes. The first prototype product contained recycled PLA fractions, validating the potential to reintroduce these recycled materials into new packaging applications without compromising quality or processing performance. This confirms the technical feasibility of a closed-loop recycling route for bio-based plastics.
These results collectively represent a significant step beyond current industrial practice in sorting and recycling of bio-based plastics, offering validated methods and pathways for high-quality recycling compatible with both chemical and mechanical routes.
To ensure further uptake and large-scale success, key enabling actions include:
• Further demonstration at pilot and industrial scale to validate process robustness under real operational conditions;
• Standardisation of testing and quality criteria for recycled bio-based plastics to support market confidence and regulatory compliance;
• Integration into existing EPR (Extended Producer Responsibility) frameworks to incentivise collection and recycling of bio-based plastics.
• International dissemination and alignment with EU Circular Economy and Bioeconomy strategies to enhance market access and cross-border uptake.
Together, these advances position the project outcomes as beyond the state of the art in the circular management of bio-based plastics, paving the way toward a fully circular, low-impact bio-based packaging value chain.

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