Bio-soot & carbon-black replacement

01Overview and value chain

Markers: [EC: EPA chemical/environmental product oversight / EU REACH & ISCC PLUS mass-balance certification / EU tire-labelling rolling-resistance regulation | OECD: Bio-based materials | Regulator: EPA (USA), REACH (EU)]

Bio-soot and carbon-black replacement covers two distinct routes to displacing virgin fossil carbon black — the reinforcing filler and pigment behind most rubber, tire and plastics products — and this Industry’s live sourcing surfaced real, well-documented companies on both, which is worth stating plainly rather than blurring: one route is genuinely bio-based (biological feedstock), and the other is circular (recycled end-of-life-tire feedstock, not biological in origin but displacing the same fossil demand). On the bio-based side, Canada’s FPInnovations — a forest-products research institute — has developed a hydrothermal carbonization (HTC) process that converts black liquor, the lignin-rich byproduct stream of kraft wood pulping, directly into a carbonaceous rubber filler without a separate drying step; tested in styrene-butadiene rubber blends, the filler restored more than 60% of the mechanical strength lost when virgin carbon black was cut by 15%. On the circular side, four companies convert end-of-life tires rather than virgin fossil feedstock into reinforcing carbon through two different technical routes: Cabot Corporation’s EVOLVE Sustainable Solutions platform and Orion Engineered Carbons’ ECORAX Circular line both process tire pyrolysis oil (TPO) into new circular carbon black grades under ISCC PLUS mass-balance certification, with production validated across the US, Brazil, Czech Republic, Indonesia and — notably — China (Orion’s Qingdao plant, Cabot’s Tianjin plant); Birla Carbon’s Continua Sustainable Carbonaceous Material (SCM) instead finishes and packs the solid carbonaceous char recovered directly from tire pyrolysis (fed by Circtec’s pyrolysis facility in the Netherlands) at a production line in Trecate, Italy; and India’s Epsilon Carbon sells Terrablack, a recovered-carbon-black and tire-derived-oil product line built on the company’s own backward-integrated production, claiming a 40-50% lower global-warming-potential footprint than virgin carbon black.

The key directions of bio-soot and carbon-black replacement are:

1. Lignin/black-liquor hydrothermal-carbonization rubber filler: FPInnovations converts black liquor — the lignin-rich chemical-recovery stream of kraft pulping — into a solid carbonaceous rubber filler via hydrothermal carbonization at 200-500°C and 2-40 MPa in water, without requiring drying or extensive purification of the feedstock; tested in styrene-butadiene rubber, the filler restored over 60% of mechanical strength lost when virgin carbon black content was reduced by 15%.
2. Tire-pyrolysis-oil mass-balance circular reinforcing carbon: Cabot Corporation’s EVOLVE Sustainable Solutions platform and Orion Engineered Carbons’ ECORAX Circular line (200, 210 and 215 grades for tires and mechanical rubber goods) both process tire pyrolysis oil under ISCC PLUS mass-balance certification into new circular carbon black, with Cabot validated across 13 ISCC PLUS-certified sites spanning the US, Brazil, Czech Republic, Indonesia and China, and Orion producing ECORAX Circular in both Poland and a newly launched Qingdao, China facility.
3. Direct recovered carbon black from tire-pyrolysis solids: Birla Carbon’s Continua SCM line finishes and packs solid carbonaceous material recovered directly from end-of-life-tire pyrolysis — sourced from Circtec’s newly opened pyrolysis facility in the Netherlands and processed at a dedicated production line in Trecate, Italy — designed to replace portions of traditional carbon black in both rubber and non-rubber applications; a Continua 8030 grade targets the Indian subcontinent and Asia specifically.
4. Backward-integrated recovered carbon black for the domestic tire industry: India’s Epsilon Carbon sells Terrablack, a recovered-carbon-black and tire-derived-oil (TDO) product line — Terrablack 3310 for heavy-duty tire treads (high wear resistance) and Terrablack 6615 for tire sidewalls, hoses, belts and sealing systems — built on the company’s own backward-integrated production and claiming a 40-50% lower global-warming-potential footprint than virgin carbon black.

Sectoral value chain

[kraft-pulping black liquor / end-of-life tires] ──> [hydrothermal carbonization / tire pyrolysis (solid char or TPO)]
                                                                          │
                                                       (mass-balance certification / direct finishing)
                                                                          │
                                                                          ▼
[rubber compound / tire] <─── [performance validation] <─── [reinforcing carbon finishing]

Value chain levels

Cross-cutting technologies of the sector:

• Lignin/black-liquor HTC rubber filler (Lignin/Black-Liquor HTC Rubber Filler): FPInnovations’ hydrothermal-carbonization process, converting kraft-pulping black liquor into a solid carbonaceous rubber filler without a drying step, restoring over 60% of mechanical strength at a 15% carbon-black reduction in SBR blends.
• Tire-pyrolysis-oil mass-balance circular carbon (Tire-Pyrolysis-Oil Mass-Balance Circular Carbon): Cabot’s EVOLVE and Orion’s ECORAX Circular platforms, both converting end-of-life-tire pyrolysis oil into new circular reinforcing carbon under ISCC PLUS mass-balance certification.
• Recovered carbon black from tire-pyrolysis solids (Recovered Carbon Black From Tire-Pyrolysis Solids): Birla Carbon’s Continua SCM and Epsilon Carbon’s Terrablack, both finishing solid carbonaceous char recovered directly from end-of-life-tire pyrolysis into reinforcing-grade product.

02US

The US and Canada anchor two different ends of this Industry: Cabot Corporation (Boston, founded 1882) supplies ISCC PLUS-certified circular reinforcing carbon at global scale, while Canada’s FPInnovations supplies the genuinely bio-based research underpinning a lignin-derived alternative.

Cabot’s global EVOLVE circular-carbon platform and FPInnovations’ lignin rubber-filler research

• Cabot Corporation (Boston, Massachusetts; founded 1882): its EVOLVE Sustainable Solutions platform converts end-of-life-tire pyrolysis oil into circular reinforcing carbons under an ISCC PLUS mass-balance approach; validated production spans 13 ISCC PLUS-certified sites, including Louisiana (USA), Mauá (Brazil), Valašské Meziříčí (Czech Republic), Cilegon (Indonesia) and Tianjin (China) — a global rather than single-market rollout; Dunlop and Cabot are exploring commercial adoption of circular reinforcing carbon together.
• FPInnovations (Vancouver, Canada; founded 2007): a non-profit forest-products research institute that developed a hydrothermal-carbonization process converting black liquor — kraft pulping’s lignin-rich chemical-recovery byproduct — directly into a solid carbonaceous rubber filler, processed at 200-500°C and 2-40 MPa in water without requiring a separate drying or extensive purification step; tested in styrene-butadiene rubber blends, the filler restored over 60% of the mechanical strength lost when virgin carbon black content was cut by 15%, opening a pulp-mill-profitability angle alongside the carbon-black-displacement one.
• EPA chemical/environmental product oversight: the operative US regulatory context governs both circular carbon black (a reprocessed industrial material) and any future commercialized lignin-based filler under general chemical and environmental product frameworks, rather than a dedicated approval pathway specific to this Industry.

03CN

China hosts real production capacity for this Industry even though the operating companies are foreign-owned: Orion Engineered Carbons and Cabot Corporation have each stood up ISCC PLUS-certified circular-carbon-black manufacturing on Chinese soil, layered onto a large domestic conventional carbon-black industry now facing its own environmental-standard tightening.

Foreign-owned circular-carbon-black manufacturing on Chinese soil, atop a large domestic carbon-black base

• Orion Engineered Carbons’ Qingdao plant: began producing ECORAX Circular carbon black (grades 200, 210 and 215) from tire pyrolysis oil under ISCC PLUS certification in 2026, complementing Orion’s existing European circular-carbon-black capacity in Poland — the company’s first step toward globally offering circular carbon black grades from a China-based facility.
• Cabot Corporation’s Tianjin plant: validated as part of Cabot’s Asia-Pacific EVOLVE circular-reinforcing-carbon expansion alongside Cilegon, Indonesia, completing circular-carbon production capability across Asia, Europe and the Americas.
• Domestic market context: China’s conventional carbon-black industry remains large (built on coal-tar-derived feedstocks — carbon black oil, anthracene oil, coal tar), with a dedicated national standards system and industry association; live sourcing this cycle did not confirm a Chinese-owned company producing a bio-based or circular carbon-black product of its own at the scale of the foreign-owned Qingdao and Tianjin facilities, though a parallel and real “bio-based rubber additive” (生物基橡胶助剂) market — plant-oil, lignin, rosin and sugar-derivative substitutes for petroleum-based plasticizers, softeners and antioxidants in tires, hoses and seals — is active among leading Chinese rubber-goods manufacturers under tightening EU REACH and tire-labelling rolling-resistance pressure, signalling adjacent domestic bio-based capability without yet a confirmed carbon-black-specific originator.

04EU

The EU supplies one leg of the ISCC PLUS mass-balance circular-carbon-black route through Luxembourg-headquartered Orion Engineered Carbons, operating under the same REACH and tire-labelling regulatory pressure driving demand for lower-carbon reinforcing material across the bloc.

Orion Engineered Carbons’ ECORAX Circular platform

• Orion Engineered Carbons (Luxembourg; NYSE: OEC; founded 2011): its ECORAX® Circular line converts tire pyrolysis oil into ISCC PLUS mass-balance-certified circular carbon black — ECORAX Circular 200 is a hard black for tires, while 210 and 215 serve both tires and mechanical rubber goods; European-scale production in Poland was joined in 2026 by a new Qingdao, China facility, extending the mass-balance-certified supply chain globally while keeping ISCC PLUS transparency and traceability standards.
• EU REACH and tire-labelling regulation: REACH governs the chemical registration of circular and conventional carbon-black materials placed on the EU market, while the EU’s tire-labelling regulation’s rolling-resistance requirements create commercial pressure for reinforcing-carbon suppliers — whether bio-based, circular or conventional — to demonstrate lower-carbon and performance-equivalent alternatives to virgin fossil carbon black.

05Leading companies and research institutes

06Tech stack and innovations

The bio-soot-and-carbon-black-replacement stack splits into a genuinely bio-based branch and a circular, tire-derived branch, both displacing the same virgin fossil carbon black but through structurally different feedstock and process chemistry.

1. Lignin/black-liquor hydrothermal carbonization:
   • FPInnovations’ HTC process converts black liquor directly into a solid carbonaceous filler at 200-500°C and 2-40 MPa in water, skipping the drying and extensive purification steps that would otherwise be needed to handle a wet, chemically complex kraft-pulping byproduct stream.
   • The over-60%-strength-restoration result at a 15% carbon-black reduction in SBR rubber gives this research-stage technology a concrete performance benchmark rather than only a directional sustainability claim — the kind of result that typically precedes a pilot-to-commercial transition.
2. Tire-pyrolysis-oil ISCC PLUS mass-balance circular carbon:
   • Cabot’s EVOLVE and Orion’s ECORAX Circular both take the liquid-oil route: tire pyrolysis oil is fed into existing carbon-black manufacturing infrastructure under an ISCC PLUS mass-balance accounting system, allowing a defined proportion of circular content to be attributed to output grades without requiring a fully dedicated, separate production line for every batch.
   • Multi-continent validation — Cabot’s 13 ISCC PLUS-certified sites, Orion’s Poland-plus-Qingdao footprint — signals this is scaling as a global reinforcing-carbon supply-chain shift rather than a boutique regional product.
3. Recovered carbon black from tire-pyrolysis solids:
   • Birla Carbon’s Continua and Epsilon Carbon’s Terrablack instead take the solid-char route: carbonaceous material recovered directly from tire pyrolysis is finished and packed as reinforcing carbon, a technically distinct path from the TPO-mass-balance route that keeps a more direct physical link between the recovered material and the finished product.
   • Epsilon Carbon’s claimed 40-50% global-warming-potential reduction versus virgin carbon black, alongside Birla Carbon’s dedicated Continua 8030 grade for the Indian subcontinent and Asia, signals India’s tire industry (over 200 million tyres produced annually) as a significant demand anchor for this route specifically.

07Value chains and production pipelines

Industrial pipeline of bio-soot and carbon-black replacement (from black liquor or end-of-life tires to reinforcing carbon)

┌───────────────────────────┐      ┌───────────────────────────┐
│ 1. Feedstock sourcing     │ ───> │ 2. Carbonization /        │
│                            │      │    pyrolysis               │
└───────────────────────────┘      └───────────────────────────┘
                                                  │
                                                  ▼
┌───────────────────────────┐      ┌───────────────────────────┐
│ 4. Performance             │ <─── │ 3. Reprocessing /         │
│    validation               │      │    certification            │
└───────────────────────────┘      └───────────────────────────┘
              │
              ▼
┌───────────────────────────┐      ┌───────────────────────────┐
│ 5. Application in rubber   │ ───> │ 6. Carbon and lifecycle   │
│    and tires                │      │    fate                    │
└───────────────────────────┘      └───────────────────────────┘

Stage 1: Feedstock sourcing

Kraft-pulping black liquor feeds FPInnovations’ research in Canada; end-of-life tires feed Cabot’s, Orion’s, Birla Carbon’s and Epsilon Carbon’s circular-carbon-black production, with Circtec’s Netherlands pyrolysis facility supplying Birla Carbon’s Continua line specifically.

Stage 2: Carbonization / pyrolysis

Hydrothermal carbonization converts black liquor into a solid carbonaceous filler at 200-500°C and 2-40 MPa in water (FPInnovations); tire pyrolysis yields either solid recovered char (Birla Carbon, Epsilon Carbon) or tire pyrolysis oil, TPO (Cabot, Orion), the fork between the solid-char and liquid-oil circular routes.

Stage 3: Reprocessing / certification

TPO is reprocessed into new circular carbon black grades under ISCC PLUS mass-balance certification (Cabot EVOLVE, Orion ECORAX Circular); recovered solid char is finished and packed directly into reinforcing-grade product (Birla Carbon Continua SCM at its Trecate, Italy line; Epsilon Carbon’s Terrablack).

Stage 4: Performance validation

Mechanical-strength restoration is benchmarked in styrene-butadiene rubber blends (FPInnovations, over 60% restored at a 15% carbon-black cut); tire-tread, sidewall, hose, belt and mechanical-rubber-goods grades are qualified against incumbent virgin-carbon-black performance (Cabot, Orion, Birla Carbon, Epsilon Carbon).

Stage 5: Application in rubber and tires

Reinforcing carbon and filler grades are compounded into tire treads (Terrablack 3310, ECORAX Circular 200), sidewalls/hoses/belts/sealing systems (Terrablack 6615, ECORAX Circular 210/215), and mechanical rubber goods and non-rubber/plastics pigmentation applications (Continua SCM).

Stage 6: Carbon and lifecycle fate

Black liquor is valorized into a rubber filler rather than combusted only for energy recovery; end-of-life tires are diverted from landfill or incineration into reinforcing-carbon feedstock; virgin fossil carbon-black demand is displaced across both routes, with Epsilon Carbon’s Terrablack specifically claiming a 40-50% lower global-warming-potential footprint than virgin carbon black.