Carbon black alternative: Sustainable industrial opportunities and use cases
The tire industry is a major consumer of Carbon Black, using 70 per cent of the material.
The disruptions to Carbon Black supply chains, rising costs of the typical feedstock fossil fuels for
Carbon black alternative: Sustainable industrial opportunities and use cases
The tire industry is a major consumer of Carbon Black, using 70 per cent of the material.
The disruptions to Carbon Black supply chains, rising costs of the typical feedstock fossil fuels for producing Carbon Black, sustainability regulations, and stakeholder pressure have industry leaders concerned about the future of Carbon Black.
Luckily, there are sustainable options like a Carbon Black alternative, not as a direct replacement but with similar properties to Carbon Black, available on the market. In this article, you will learn about recovered Carbon Black as a sustainable option for several industries and use cases.
Types of Carbon Black
Carbon Black is a synthetic material made of 98 per cent carbon. Petroleum oil, gas, and coal tar are the common raw ingredients used to produce virgin Carbon Black (vCB) by burning the feedstocks at very high temperatures in reactors to vaporise the carbon. After cooling, the result is a paracrystalline spherical substance available as a powder.
Different manufacturing processes and feedstocks produce varying particle sizes, surface area, and aggregate structure, which define the properties of the vCB. So there are many grades of Carbon Black.
Tire manufacturing uses most vCB grades to stabilise and strengthen rubber products, such as tire treads, sidewalls, tubes, belts, and carcasses:
- Grades with smaller particles, such as N110, N220, and N234, have high reinforcing, abrasion resistance, and tear strength. These grades are used as reinforcing filler materials to make rubber elastomers that form tread.
- Medium to high reinforcing grades like N330, N339, and N550 are found in treads, inner liners, carcasses, and sidewalls.
- Medium reinforcing vCB grades like N660 and N770 have low heat build-up and prevent tire deformation. They’re suitable for sidewalls, inner liners, and sealing rings.
- Low reinforcing vCBs with high loading capacity and elongation are suitable for inner liners and belts.
- Carbon Black is also a pigment that colors the tires black. It also protects the tires from the harmful effects of ultra-violet (UV) light and ozone to extend tire lifespan.
The cumulative effect of vCBs makes tires safer and more durable for driving. There are 21.5 per cent and 22 per cent of vCBs in passenger and truck tires.
The use of fossil fuels to provide feedstock and energy for the manufacture of vCBs has increasingly become an image and compliance issue for the tire industry. Moreover, each ton of vCB produces around 3 tonnes of greenhouse emissions.
Recovered Carbon Black: a sustainable option
The tire industry needs new Carbon Black options that are sustainable to avoid the environmental problems created by vCB manufacturing and meet consumer demands for green products.
Recovered Carbon Black (rCB) can be a sustainable alternative to vCBs. Instead of new fossil fuels, rCB production uses end-of-life tires (ELTs) as feedstock in pyrolysis.
However, rCB is not a 1:1 replacement for any particular vCB grade.
rCB is a new, unique grade with its own set of properties. The American Society for Testing and Materials (ASTM) International workgroup 36, set up in 2017, is still developing quality standards for rCB.
The properties of rCB reflect the mix of passenger and truck ELTs used in pyrolysis. It’s close in its properties to N660 because this grade is found in significant quantities in tires of all vehicles. However, minor amounts of high reinforcing vCB grades found in tire components will also be part of rCB. Moreover, the chemicals in the waste tires will also make their way into the rCB affecting its properties.
rCB is a sustainable Carbon Black option because of its small carbon footprint and circularity. The manufacturing process of Contec rCB produces 2 tonnes fewer carbon emissions than vCBs. Whereas vCB requires 2 tonnes of sulphur-rich fossil fuels, 1 tonne of rCB can be made from just three ELTs.
Tire producers can solve their waste problems and use recycled materials in their tires to meet requirements set by the EU End-of-life Vehicles Directive by using pyrolytic products.
Pyrolysis at Contec
There are around 20 to 30 types of pyrolysis processes, but not all are created equal.
Conventional pyrolysis systems can’t guarantee consistency in the quality of rCB. Contec has improved the pyrolysis process with several innova