An EU-funded Horizon Europe initiative known as the Rubbio project is aiming to manufacture high-performance, bio-based synthetic rubbers: specifically polybutadiene (PB), styrene-butadiene rubber (SBR), and nitrile butadiene rubber (NBR), from starch-rich bread and potato waste. Besides the production of three rubber types, the project will aim to cut carbon emissions from butanediol production by 41% and reduce Europe’s reliance on imported rubber.
The project will address the challenges by developing sustainable, scalable, and high-performance rubber materials through the synthesis of key intermediates (2,3-butanediol and propionic acid), monomers (1,3-butadiene, acrylonitrile, and styrene), and rubber types (polybutadiene rubber – PB, SBR, NBR) from starch-rich food waste, which serves as a source of sugars for microbial fermentation.
Using biomanufacturing approaches and chemical engineering principles in an integrated manner, the project targets the decarbonisation of synthetic rubber use sectors and reduces the EU’s strategic dependence on imported natural rubber, it adds.
The four-year project is expected to:
· enable over 95% efficient conversion of starch feedstock into fermentable syrup, creating a marketable product with an expected selling price of €400–600 per tonne.
· reduce carbon emissions by 41% in butanediol production compared to fossil-based methods, or 82–89% when biogenic emissions are excluded from total CO? emissions.
· lower the carbon footprint of propionic acid (PA) production to below 2 kg CO2, representing a 35% reduction, by avoiding energy-intensive evaporation processes, recycling extractants, reducing media requirements through immobilised cells, and increasing volumetric productivity using high-rate fermenters.
· reduce the cost of bio-based propionic acid by approximately 35%, decreasing production costs from EUR1.25 – 1.70 per kg towards the petrochemical price of EUR0.85 per kg.
· establish a reliable industrial feedstock supply, securing over 1,500 tonnes of bread and potato waste per week, demonstrating the feasibility of large-scale food-waste transformation.
· reduce pressure on natural rubber supply chains, lowering dependency on extensive rubber tree use through the development of alternative bio-based rubber materials.
develop three new value chains based on food waste, creating a replicable model that can unlock local bioeconomy potential across the EU.
· support job creation in the green technology sector and contribute to increasing public acceptance of bio-based products.
The project’s consortium will span partners from countries like Spain, UK and Belgium, and will be coordinated by Spanish research organisation Fundacion Aitiip.