Articles

Pyrolysis has been used as a means of recycling end-of-life tires or other post-industrial and/or consumer rubber products for several years. This process produces several valuable secondary raw materials that support the circular economy. One such material, sustainable carbonaceous material (SCM), can be used as a sustainable alternative to carbon black in many applications where traditional virgin carbon black is used. Although traditionally seen as suitable only for low value applications, recent advances allow the use of SCM in a wider range of higher value products. These advances are helping compounders and OEMs meet their sustainability targets by allowing the use of a higher percentage of sustainable materials in their formulations with minimal adjustments or loss in performance.

A constantly developing automotive industry and the growing number of vehicles generate massive tire demand. The worldwide demand is expected to reach more than 3 billion units by 2025, with an indicated rise of 4% and an estimated sales forecast of $258 billion. Further management and recycling of end-of-life tires (ELTs) is still a critical challenge globally which needs to be overcome, since it produces severe land, water and air pollution. The development of low cost, environmentally benign and industrial scale tire recycling methods is gaining more attention, garnering much ongoing research to address the problem. However, due to the complex and heterogeneous three-dimensional structure of the tire, the development of efficient, industrial scale devulcanization technologies that can electively recover the main components of the tire, such as carbon black and rubber, is rare.

The concept of an electric vehicle developed nearly 200 years ago, with European and U.S. inventors at the forefront. However, as the electric vehicle was sought after, so too was the gasoline powered vehicle, which had an improved internal combustion engine. Electric vehicles were favored, though, as they were rendered quiet and did not emit odorous gases like the other vehicle types. The ease of driving made it very popular among urban residents. Such advantages propelled vehicle sales in the early 1900s; although, despite such early popularity, electric vehicles just about faded by 1935, as gas became cheap and ever more abundant. Decades ensued, and it was not until global environmental concerns and the rise in oil prices that more research and development was dedicated to the electric vehicle.

Some products offered to the tire industry involve replacing existing technology with a renewable source-derived substitute. Tire companies themselves are also innovating new sustainable tire materials, such as the new sources of latex rubber under development by Continental and Bridgestone. Replacing reactive products, such as antioxidants, antiozonants and accelerators, may be considered more challenging, as this task involves inventing a new molecule versus replicating an existing structure with a renewable raw material source. The vulcanization process is a particularly challenging area for creating sustainable alternatives, since the reactivity of this chemical system is critical both to the manufacturing needs and to the performance of the rubber system.