Enhanced solvolysis contributes to the future of composite recycling

Fast and efficient solvolysis

Solvolysis faces two main challenges. It is a lengthy process and fibres tend to get damaged during the procedure. However TNO is developing an innovative solvolysis technology by combining the solvolysis process with a physical treatment methodology.

This technology provides a significant step forward in recycling these hard-to-recycle composite materials. This is what we call Enhanced Solvolysis. Enabling a fast way of separation and recovery of both resin (polymer matrix) and high-quality fibers from composite materials. Making TNO's solvolysis process a potential game-changer.

What is solvolysis?

Solvolysis is a chemical process that breaks down polymers using solvents. In the context of thermoset composites, this involves heating up a piece of material in the solvolysis mixture. The heat and the mixture cause the composite to disintegrate, freeing the fibers from the polymer matrix.

This process allows for the recovery of both the fibers and resin that can be reused in new composites. With enhanced solvolysis we accelerate the reaction through prior application of an external field, thereby improving the reaction rate or yield while using similar or more benign reaction conditions.

Successful automotive industry collaboration

To illustrate the effectiveness of solvolysis, TNO partnered with key players in the automotive industry. Tests demonstrated that fibers recovered from car body composites through solvolysis retained similar strength to new fibers, making them suitable for reuse. This not only reduces waste but also lowers the demand for new raw materials required to produce both fibers and polymers.

No innovations without a challenge

Developing the solvolysis process was not without its challenges. Finding the right balance between breaking down the composite and preserving the quality of the recovered materials required extensive research. TNO's R&D Hub for waste processing worked on enhancing the solvolysis process to make it faster and more efficient.

One of various tested enhancers proved to be significantly more effective than the others. This method allowed the reaction to proceed much faster under similar conditions thus protecting the fibres and creating high-quality outputs.

Impact on the industry

TNO's enhanced solvolysis technology could have a strong impact on the recycling industry. Materials that previously only could be down-cycled, such as those used in office chairs, car bodies, and wind turbine blades, can now be recycled with this technology. Therefore, this new TNO technology not only promotes sustainability but also helps achieve recycling targets.

TNO's enhanced solvolysis is poised to become a key technology in the recycling industry. Offering a technology that enables the recycling of thermoset composites, TNO invites companies to collaborate on sustainable solutions for their composite materials.