Recyclable Elastomeric Plastics safely and sUstainably designed and produced via enzymatic Recycling of Post-cOnsumer waSte strEams

Project Information

REPurpose

Grant agreement ID: 101057971

DOI

10.3030/101057971

EC signature date 23 May 2022

Start date 1 September 2022

End date 31 August 2026

Funded under

• Digital, Industry and Space

Total cost

€ 6 373 176,75

EU contribution

€ 6 058 487,00

Coordinated by

BIO BASE EUROPE PILOT PLANT VZW
Belgium

Periodic Reporting for period 2 - REPurpose (Recyclable Elastomeric Plastics safely and sUstainably designed and produced via enzymatic Recycling of Post-cOnsumer waSte strEams)

Reporting period: 2024-03-01 to 2025-08-31

Summary of the context and overall objectives of the project

Due to their wide applications, the annual plastic production is expected to quadruple by 2050. However, their production largely relies on fossil-derived chemicals and, when disposed, plastics accumulate in landfills or nature causing global pollution. It is essential to find resource-efficient solutions and reach high-quality recycling, thus closing the circular economy loop and reducing the environmental impacts. In order to do so, it is essential to address design issues as it is estimated that over 80% of impacts are determined during this phase. The proposed European Safe-and-Sustainable-by-Design (SSBD) framework focuses on integrating safety, circularity, and functionality from the early design stage to end-of-life, aiming to mitigate environmental impacts. The Horizon Europe funded REPurpose initiative aligns with the SSBD concept by considering waste as part of the solution. It aims to create new, endlessly recyclable plastics from local post-consumer waste as sustainable and secure raw materials. This involves targeted biochemical conversion of the waste streams into chemical building blocks and polymerisation thereof into innovative plastics, all while incorporating design features for reuse and controlled recycling.

As such, REPurpose will deliver a platform of waste-based, recyclable polymers and products with adjustable functional properties for hard-to-recycle applications in the consumer goods, construction and automotive industry. The project adopts a cross-sectorial value chain approach, involving waste handlers, regulators, specialty material producers, technology developers, and end users. The project will compile best practices and contribute to SSBD criteria development as well as shaping policy recommendations.

In conclusion, the transformative potential of the REPurpose initiative presents an opportunity to address the escalating challenges posed by the increasing global consumption of materials, particularly in the field of plastics.

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

Various types of local post-consumer waste have been pretreated for biochemical conversion into REP (Recyclable Elastomeric Plastics) building blocks. An enzyme-based process to degrade paper and cardboard waste into 2nd-generation sugars was optimised and scaled up. These sugars, which do not compete with food sources, were successfully converted into polymer building blocks via fermentation using engineered bacteria. Biotechnological protocols for producing key monomers (glutaric and muconic acid) were scaled up and supplied for polymer synthesis.

In parallel, several enzymes were characterised, selected, and produced at lab and pilot scale to depolymerise different types of pretreated plastic waste into similar building blocks, now used in recycling trials.

Further down the chain, a broad library of new REP polymers was developed using commercial and validated waste-based building blocks. These polymers were characterised for their functional properties, incorporating feedback from application developers and end users. Selected formulations were scaled up, and toxicity testing confirmed their safety for human health and the environment. Some REP polymers were compounded with natural fibres and processed using industrial techniques. Technical requirements were defined, and product design for targeted applications is ongoing.

Efforts focus on ensuring REP polymers and products are reusable, recyclable, and sortable from other plastics at end-of-life. A spectral detection method was validated for REP identification in industrial sorting, with successful sorting trials supporting practical recovery.

Key innovations were identified for business exploitation. Communication efforts included updated materials, a promotional campaign, editorial publications, and dissemination at numerous events, including collaborations with Sister and Cousin projects.

Life cycle, techno-economic, and social assessments are underway to evaluate sustainability, fully integrating the SSbD concept. An inventory of potentially toxic plastic additives was compiled, and compliance with existing regulations is ensured. A regulatory framework with policy recommendations, initial guidelines, and a technology trends report were developed. Industry input was collected via questionnaires, and work continues on a draft for a new recycling-related standard.

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)

Different steps of the post-consumer-waste-to-functional-plastics value chain are being developed in parallel. An enzymatic process to degrade pretreated paper and cardboard (P&C) waste into sugar hydrolysate was optimised and scaled to 1,500 L. This 2G feedstock was validated in 150 L fermentations using an engineered microorganism to produce glutaric acid as a polymer building block. Similarly, muconic acid was produced from lignin using various microbes, scaled up, and hydrogenated into adipic acid for polymerisation.

In parallel, enzymes for depolymerising pretreated plastic waste into similar building blocks were designed, selected, and produced at up to 150 L scale. Work is ongoing to upscale plastic depolymerisation processes.

Commercial analogues of waste-based monomers and one actual waste-based monomer have been polymerised into REP prototypes. By varying building block functionality, chain length, and polymerisation conditions, 26 REP prototypes with diverse architectures and functional properties were developed. One REP grade matched properties of Hytrel® (partly biobased); others showed more rigid yet processable profiles. Several have been selected for scale-up, with optimisation underway. Final validation using actual waste-based monomers will confirm the robustness of the REPurpose concept.

Technical requirements (durability, mechanical properties) have been defined for targeted applications (construction, automotive, consumer goods/sportswear). REP materials, both rigid and elastic, were tested in various processing techniques (sheets, injection moulding, 3D printing, foaming, extrusion). Initial product prototypes were made from commercial materials, with REP-based prototypes to follow. REP compounds with natural fibres have also been produced.

While REPurpose covers activities up to TRL 5, further development, demonstration, and market entry will require additional public or private funding.

Transversal activities include:
- Ensuring REACH/CLP compliance and proposing relevant framework conditions;
- Creating a public inventory of plastic additives for safe, biobased selection;
- Analysing spectral data to support REP identification during sorting;
- Conducting social, environmental, and economic assessments to guide development;
- Promoting Responsible Research and Innovation and Open Science within the consortium.

REPurpose concept