One central target of the BlackCycle project is to produce so-called Sustainable Carbon Black (sCB) from recovered oils (r-oil) from the pyrolysis process using End-of Life Tires (ELT) as Feedstock.
The primarily obtained oil is called Crude Tire Tar (CTT). This name is in line with the naming of other Carbon Black oils like i.e. Steam Cracker Tar (SCT) or Crude Coal Tar (CCT). The flashpoint of the CTT is found to be very low and thus it must be considered as highly flammable oil. This is a major barrier for the usage of CTT in Carbon Black industry so far. As the purpose of the BlackCycle project is to enhance such oils a CTT was distilled and separated into a light fraction, which is called Light Tire Tar (LTT) and a heavy fraction, which is called Heavy Tire Tar (HTT). The HTT was found to have a flashpoint above 65°C which allows a flawless usage as a Carbon Black feedstock.
The obtained oils have been thoroughly analysed. Generally, it can be said that only HTT oils have suitable flashpoints. We also observed in all r-oils lower Carbon content and lower aromatics contents than in oils normally used in the industry to produce Carbon Black.
We used one HTT for trials in ORION’s mini plant. First indications show a very good match compared to standard N234 and N347 Carbon Blacks, both analytically and lab results for in-rubber properties. Samples of s-N234 have been sent to Michelin for further testing. Nevertheless, we have observed very low yields compared to standard oils used in the CB production, mainly because of a low Carbon- Hydrogen ratio (C/H-ratio) which indicates a lower aromatic content.
Picture of a part of an CB production line: