Carbon black is what makes a tyre black, strong and hard-wearing. It is 15 to 20 per cent of a passenger car tyre, according to Continental. Almost all of it is still made from fossil oil. Recovered carbon black (rCB) — carbon black recovered from end-of-life tyres by pyrolysis — is the most direct way to complete that loop.
Where things stand
Less than 1 per cent of the carbon black in new tyres comes from recycled tyres, according to a 2023 white paper by Bridgestone and Michelin. The same paper puts the potential emissions saving at up to 85 per cent against virgin material.
The tyre makers want more. In 2022 Michelin and Bridgestone said demand for rCB could reach about one million tonnes a year by 2030, provided recycling technology keeps developing. Michelin aims for 40 per cent recycled and renewable materials in its tyres by 2030; Continental for more than 40 per cent. Both Michelin and Bridgestone target 100 per cent sustainable materials by 2050.
Why supply has not kept up
The constraint is quality, not demand.
- Ash. Virgin carbon black has under 1 per cent ash; rCB typically has 15 to 30 per cent, from the fillers and minerals in the original tyre.
- Consistency. Feedstock varies from tyre to tyre, so output varies from batch to batch. Tyre makers need the same material every time.
- Partial substitution. Current specifications do not allow rCB to replace every grade of virgin carbon black. It works in some compounds and parts of a tyre, not all.
What is changing
- Standards. ASTM's committee on carbon black has been publishing test methods written for rCB rather than borrowed from virgin carbon black, including a method for ash content (D8621) that cuts testing from about 18 hours to a few. Common tests make specifications and offtake contracts easier to agree.
- Long-term offtake. In July 2024 Continental signed a ten-year agreement to buy rCB from Pyrum Innovations, and supplies Pyrum with end-of-life tyres in turn. Continental already uses Pyrum's rCB in all new forklift tyres made at its Korbach plant.
- Policy. In India, recovered carbon black usable as a raw material for new tyres is one of five recycling outputs that earn EPR certificates.
What it means
For tyre makers, rCB is a way to cut emissions, meet recycled-content goals and secure part of a raw material at home. For recyclers, it is the highest-value output a pyrolysis plant can sell — if it meets specification. For investors, the gap between what tyre makers want and what plants can deliver to specification is where the opportunity sits.
The winners will be the plants that pair consistent feedstock with consistent quality, and sign the offtake before they build.
Related: Recycling routes and market access, Clean energy finance and clean technology investment.
Sources
- European Rubber Journal — Michelin, Bridgestone see potential for rCB demand to reach 1m tonnes by 2030 (28 November 2022)
- IO+ — Tyre giants Bridgestone and Michelin publish rCB white paper (7 November 2023)
- Tyre Trends — Reducing ash content in rCB (18 December 2025)
- Continental — ten-year purchase agreement with Pyrum Innovations (30 July 2024)