Periodic Reporting for period 1 - REPurpose (Recyclable Elastomeric Plastics safely and sUstainably designed and produced via enzymatic Recycling of Post-cOnsumer waSte strEams)
Reporting period: 2022-09-01 to 2024-02-29
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 rubbery 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 rubbery 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.
As such, REPurpose will deliver a platform of waste-based, recyclable polymers and products with adjustable functional properties for hard-to-recycle rubbery 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.
Several types of local post-consumer waste have been (pre-)treated to allow biochemical conversion into REP (Recyclable Elastomeric Plastics) polymer building blocks. An enzyme-based process to degrade paper and cardboard waste into sugars has been optimised and scaled up. These 2nd-generation sugars have been proven to be a perfect source for conversion into a polymer building block by fermentation using engineered bacteria, hence without causing competition with the food industry as is typically the case when using first-generation sugars. In the meantime, several enzymes have been characterised, selected and produced at lab scale to depolymerise different types of pretreated plastic waste into similar polymer building blocks.
Further down the value chain, a first library of new REP polymers has been developed using commercial counterparts of said REP polymer building blocks, later to be replaced by the ones produced within REPurpose after scale-up. These REP polymers are being characterised for their functional properties, while considering design feedback from application developers within the consortium and external end users. At the same time, attention is paid to developing polymers and products that are reusable or recyclable and eventually sortable from other plastics when disposed, and do not cause any harm to the environment. Life cycle, social and techno-economic assessments have been initiated to evaluate sustainability of the innovations in all its aspects. As such, the SSBD concept is fully integrated. Finally, an inventory has been made of potentially toxic plastic additives, while compliance with existing regulations and standards is ensured.
Further down the value chain, a first library of new REP polymers has been developed using commercial counterparts of said REP polymer building blocks, later to be replaced by the ones produced within REPurpose after scale-up. These REP polymers are being characterised for their functional properties, while considering design feedback from application developers within the consortium and external end users. At the same time, attention is paid to developing polymers and products that are reusable or recyclable and eventually sortable from other plastics when disposed, and do not cause any harm to the environment. Life cycle, social and techno-economic assessments have been initiated to evaluate sustainability of the innovations in all its aspects. As such, the SSBD concept is fully integrated. Finally, an inventory has been made of potentially toxic plastic additives, while compliance with existing regulations and standards is ensured.
Different steps of the post-consumer-waste-to-rubbery-plastics value chain are being developed in parallel. An enzymatic process to degrade pretreated paper and cardboard (P&C) waste into a sugar hydrolysate has been optimised and demonstrated at 1,500 L scale. This 2G feedstock was successfully validated in fermentation up to 7 L scale for growth of a newly engineered micro-organism and production of glutaric acid as polymer building block. Likewise, muconic acid production from lignin has been optimised using different microbial production organisms.
Besides enzymatic depolymerisation of P&C waste, new enzymes have been designed, selected and/or produced up to 7 L scale for the degradation of different types of pretreated plastic waste into similar building blocks. Further research is focused on thermostability of the enzymes and scalability of their production.
In the meantime, commercial counterparts of the waste-based building blocks have been tested for polymerisation into new REP polymers. Through alteration of the building block functionalities, chain length and polymerisation conditions, a library of 20 REP prototypes has been developed and analysed for its physico-chemical and mechanical properties. One REP grade was found to have similar properties to commercial thermoplastic elastomer Hytrel® (only partly biobased). Others showed interesting processability potential. Further optimisation trials, scale-up and use of actual REPurpose building blocks, originating from post-consumer waste, will be pursued in the coming period. Technical requirements for the polymers to be developed, such as durability, and mechanical properties have been defined considering the targeted applications (building, automotive, consumer goods/sportswear). Processing applications for REP materials are being screened for both rigid and elastic REP grades to open up the spectrum of feasible applications in the envisaged sectors.
All biotechnological and polymerisation processes will be optimised and scaled up to pilot scale in the coming months and years. Additional private financing or public subsidies are required for further finetuning, scale-up to demonstration scale, and market exploitation.
The core technical developments have been accompanied by transversal activities to increase their impact:
1) Ensuring REACH and CLP compliance of all building blocks produced, while analysing and proposing relevant framework conditions;
2) Developing a publicly available inventory of plastic additives, to allow proper selection (i.e. safe for use, biobased) thereof;
3) Analysing spectral data of the REP polymers and building blocks to allow their detectability from other plastics in a sorting scenario;
4) Evaluating the social, life cycle and techno-economic impact of the innovations to guide strategic decisions regarding REP development;
5) Teaching the consortium how to apply Responsible Research and Innovation and use an Open Science approach.
Besides enzymatic depolymerisation of P&C waste, new enzymes have been designed, selected and/or produced up to 7 L scale for the degradation of different types of pretreated plastic waste into similar building blocks. Further research is focused on thermostability of the enzymes and scalability of their production.
In the meantime, commercial counterparts of the waste-based building blocks have been tested for polymerisation into new REP polymers. Through alteration of the building block functionalities, chain length and polymerisation conditions, a library of 20 REP prototypes has been developed and analysed for its physico-chemical and mechanical properties. One REP grade was found to have similar properties to commercial thermoplastic elastomer Hytrel® (only partly biobased). Others showed interesting processability potential. Further optimisation trials, scale-up and use of actual REPurpose building blocks, originating from post-consumer waste, will be pursued in the coming period. Technical requirements for the polymers to be developed, such as durability, and mechanical properties have been defined considering the targeted applications (building, automotive, consumer goods/sportswear). Processing applications for REP materials are being screened for both rigid and elastic REP grades to open up the spectrum of feasible applications in the envisaged sectors.
All biotechnological and polymerisation processes will be optimised and scaled up to pilot scale in the coming months and years. Additional private financing or public subsidies are required for further finetuning, scale-up to demonstration scale, and market exploitation.
The core technical developments have been accompanied by transversal activities to increase their impact:
1) Ensuring REACH and CLP compliance of all building blocks produced, while analysing and proposing relevant framework conditions;
2) Developing a publicly available inventory of plastic additives, to allow proper selection (i.e. safe for use, biobased) thereof;
3) Analysing spectral data of the REP polymers and building blocks to allow their detectability from other plastics in a sorting scenario;
4) Evaluating the social, life cycle and techno-economic impact of the innovations to guide strategic decisions regarding REP development;
5) Teaching the consortium how to apply Responsible Research and Innovation and use an Open Science approach.