The regulatory identification of recovered carbon black (rCB) involves two distinct numbering systems, reflecting its dual identity as both a carbon-based functional filler and a dedicated circular waste-derived material. There is no single, globally exclusive CAS number assigned solely to rCB; instead, its classification depends on the regulatory framework and product grading context.
1. General Commercial CAS Number: 1333-86-4
In most global commercial and trade scenarios, recovered carbon black is classified under the generic CAS number 1333-86-4, which corresponds to amorphous carbon black. The corresponding EINECS number is 215-609-9.
This classification is based on rCB’s core material property: its primary component is elemental carbon in amorphous form, which is chemically identical to the carbon matrix of virgin carbon black. For general trade, customs declaration, and basic material classification, rCB products from tire pyrolysis, plastic pyrolysis and other sources are widely labeled with CAS 1333-86-4 across global markets, aligning with the standard identification for all carbon black products.
This generic numbering reflects the historical industry convention of grouping all carbon-based black fillers under a single material identity, regardless of production origin.
2. EU Dedicated Regulatory Identity: EC Number 954-402-4
Under the European Union’s REACH regulation, recovered carbon black derived from end-of-life tires has been granted a dedicated, independent substance identifier that distinguishes it from virgin carbon black.
In 2024–2025, the European Chemicals Agency (ECHA) officially assigned the EC number 954-402-4 to the substance formally named “Amorphous carbon and silicon dioxide recovered from processing of spent tyres” — the regulatory definition of tire-derived rCB.
This milestone marks official recognition that rCB is a distinct UVCB (Unknown or Variable composition, Complex reaction products or Biological materials) substance. Unlike virgin carbon black (EC 215-609-9, CAS 1333-86-4), which is a highly pure synthetic product, rCB naturally contains embedded inorganic ash, silica residues and trace components inherited from its waste feedstock. The dedicated EC number formalizes this compositional difference and creates a separate regulatory pathway for circular carbon materials under EU law.
3. Why Two Identification Systems Exist
The coexistence of the generic CAS number and the dedicated EC number stems from the dual nature of rCB:
- From a chemical property perspective, rCB is predominantly amorphous carbon, so it falls under the broad carbon black classification of CAS 1333-86-4 for basic material identification.
- From a regulatory and sustainability perspective, rCB is a waste-derived material with a unique compositional fingerprint, requiring dedicated substance registration to accurately reflect its hazard profile, lifecycle origin and circular economy status.
It should be noted that the dedicated EC 954-402-4 currently applies specifically to rCB produced from end-of-life tire pyrolysis. rCB from other feedstocks such as waste plastics and biomass may still fall under the general carbon black classification in most jurisdictions.
4. Implications for Industrial Production and Compliance
For rCB producers, refining quality directly affects regulatory compliance and product classification. Crude pyrolysis char with high impurity content and inconsistent composition cannot meet strict regulatory identification standards.
Precision processing systems such as those engineered by JACAN Powder Equipment play a key role in producing specification-grade rCB that aligns with global regulatory requirements. Through magnetic separation, ultra-fine grinding with D90 < 10μm fineness control, high-precision aerodynamic classification and multi-parameter intelligent optimization, JACAN systems deliver rCB with consistent composition, controlled ash content and uniform particle size distribution. This level of quality consistency enables producers to meet both general trade classification under CAS 1333-86-4 and stricter regional regulatory frameworks such as the EU’s dedicated EC substance registration. In summary, 1333-86-4 remains the most widely used CAS identifier for recovered carbon black in global commercial practice. In the EU regulatory system, tire-derived rCB holds the dedicated EC number 954-402-4 as a formally recognized distinct circular material. As the industry continues to mature, more regions are expected to introduce dedicated regulatory identities to support the traceability and certification of sustainable carbonaceous materials.
