Evonik Advances Tire Recycling with Breakthrough Process to Increase Recycled Rubber Use

Evonik Advances Tire Recycling with Breakthrough Process to Increase Recycled Rubber Use

(IN BRIEF) Evonik has developed a breakthrough process that allows up to four times more recycled rubber to be used in new tire production. Traditionally, only 5% of recycled rubber could be reused due to the vulcanization process, which makes it difficult to incorporate into new materials. Evonik’s new method uses vinyl silanes to break down sulfur bonds in recycled rubber, allowing up to 20% to be reused in new tires. The company is now working to scale this process for industrial use, aiming to enhance resource efficiency and sustainability in the tire industry, which produces over 2,000 tires every minute globally.

(PRESS RELEASE) ESSEN, 17-Sep-2024 — /EuropaWire/ — Evonik is taking significant strides toward improving tire recycling with a groundbreaking process that allows up to four times more recycled rubber to be used in the production of new automobile tires. Traditionally, only 5% of recycled rubber from end-of-life tires could be incorporated into new tire manufacturing due to the challenges posed by the vulcanized structure of rubber, which hampers its ability to blend effectively with new materials. Evonik’s new process, developed by its research team, addresses these challenges and moves the industry closer to a circular, sustainable approach.

Overcoming Vulcanization Barriers

New tire rubber is produced through vulcanization, a process that creates strong sulfur bonds between rubber molecules, resulting in a durable, three-dimensional network. However, this same process makes it difficult to reuse ground tire rubber in new applications, as the vulcanized structure remains intact, limiting its compatibility with new rubber materials.

To address this issue, Evonik’s researchers have developed a method that uses vinyl silanes to break down these sulfur bonds in recycled rubber, while leaving the carbon chains largely intact. This “devulcanization” process allows for much higher integration of recycled rubber into new tire production, boosting the recycled content in rubber blends to as much as 20% in laboratory trials—compared to the current industry standard of 5%.

Towards a Circular Economy for Rubber

The breakthrough holds immense potential for the tire industry, where more than 2,000 tires are produced every minute to meet global demand. Many end-of-life tires are currently recycled for secondary uses, such as playground surfaces or fuel for energy generation, but Evonik sees greater value in re-incorporating rubber back into tire manufacturing. “Rubber is far too valuable to be used only once in tires,” says Christian Mani, Project Manager for Circularity at Evonik. “We want to close the loop and make rubber part of a true circular system.”

Next Steps: Scaling for Industrial Use

While the results in lab trials are promising, Evonik is now working on scaling this process for commercial application. The team is running additional test series and trials to adapt the technology for large-scale production. The company aims to offer tire manufacturers a commercially viable solution that can be integrated into their production lines, enhancing both resource efficiency and sustainability.

The impact of such a solution would be profound, especially as the global market for passenger car tires, valued at over €100 billion annually, continues to grow. Even electric and hydrogen-powered vehicles rely on rubber tires, meaning demand will remain strong for the foreseeable future. Evonik’s innovation aligns with the broader sustainability goals of the tire industry, which is increasingly focused on reducing its environmental footprint.

By pioneering this recycling process, Evonik is positioning itself at the forefront of sustainable innovation, helping to reduce waste, conserve resources, and support a more circular economy for the tire sector.

Media Contacts:

Ruben Thiel
External Communications: HR, Digitalization
Tel +49 201 177-4299
ruben.thiel@evonik.com

Holger Seier
Research, Development & Innovation
Mobile +49 151 53 83 15 77
Holger.Seier@evonik.com

SOURCE: Evonik