What is Carbon Black?
Carbon black is a fine black powder similar to soot, since it’s difficult to clean off of hands, clothing, and other surfaces and a little bit goes a long way when turning something black.
Carbon black is the product of partially burning petroleum, coal, coal tar, and even vegetable matter. The primary market for carbon black is automobile tires as well as other commercial and industrial rubber goods. Tire OEMs use carbon black as a pigment and reinforcing agent or filler in tire compounds. Carbon black can also play a role in reducing thermal damage, which extends the life of the tire.
In recent decades, concerns about sustainability have driven the tire industry to investigate new ideas. One solution being explored is the reclamation of carbon black. Carbon black can be recovered from scrap tires via pyrolysis and used to make new tires and other manufactured rubber goods. The industry has made considerable refinements to this process over the years, and many tire OEMs and other rubber manufacturers are experimenting with the use of recovered and recycled carbon black in their products. In fact, some tire OEMs have begun mandating that tier suppliers adhere to their sustainability standards, which can include the use of recovered materials, such as carbon black. Given the power that OEMs have over the tire supply chain as a whole, many tier suppliers are eager to comply.
Another factor driving the use of recovered carbon black is price stability. The price of virgin carbon black is directly correlated with the price of oil and thus is subject to the volatility of the oil index. This can make procurement planning and budgeting difficult. However, the price of recovered carbon black is extremely steady, since its production is completely independent of the oil market. And while some sources say recovered carbon black prices are rising, recovered carbon black is often a more economical option, especially when oil prices are high. Recovered carbon black is not always a suitable alternative for virgin carbon black, but for applications in which either can be used, many manufacturers are drawn to the stability and cost effectiveness of recovered carbon black.
Recovered Carbon Black Testing
No two sources (or suppliers) of recovered carbon black can be treated as equals. Each source (or supplier) will have unique properties based on how it was used in its first service life, what type of tire or rubber product it came from, the rubber compound formulation of that product, and the pyrolysis process. Understanding the specific properties and purity of each source (or supplier) via carbon black testing is crucial to successful incorporation into a new compound.
Understanding the basic structure of the particles that comprise a source or grade of recovered carbon black is vital for designing a compound or product around it. Manufacturers need to know the particle size, surface area, and particle size distribution of the carbon black, as well as porosity and surface chemistry. These properties affect the dispersion of carbon black particles as well as the performance properties of the final compound.
It’s extremely difficult, if not virtually impossible, to achieve total purity of recovered carbon black. Raw materials analysis is an extremely important step in recovered carbon black testing. This type of sophisticated analysis can identify and quantify any trace elements still present, so you can plan your formulation around them. Experienced compounders can use these trace elements to their advantage or choose additional ingredients based on what will complement rather than conflict with elements already present.
During the recovered carbon black testing process, manufacturers may leverage small batch mixing to test the performance of experimental compounds. This allows manufacturers to compare a few different formulations using recovered carbon black, make adjustments as necessary, and choose the optimized formulation before investing in large-scale production.
Carbon Black Testing From ACE Labs
ACE Laboratories is proud to offer carbon black testing services and expert support for companies looking to use recovered carbon black in their rubber compounds and products. We offer small-batch mixing services for benchmarking the properties of compounds using recovered carbon black against virgin carbon black, as well as elemental analysis on recovered carbon black particles. We can also help you procure data on recovered carbon black particle characterization data, such as particle size, surface area, and distribution.
With our deep experience in the tire industry and the field of rubber sustainability, we can offer fresh next-level insight as you explore the possibilities of recovered carbon black. To learn more about our carbon black testing capabilities, talk to a member of our team >