Successful recycling of carbon fiber that does not spoil the material

University of Canberra experiment bodes well for the recycling of carbon fiber

(sustainabilityenvironment.com) – With experimentation and technological evolution, the world becomes increasingly complex. With it, even the materials, which however collide with a growing difficulty in recovering them when they reach the end of life. The case of recycling carbon fiber is emblematic. The material is critical for sustainable technologies such as wind turbines or electric cars, but is difficult to recycle.

However, a researcher from the University of Canberra has taken a new method out of his laboratory. It not only wastes less material but also uses less energy, leaving the carbon fiber more intact. This allows it to be transformed into more useful products than would be obtained by its complete destruction. Until now, in fact, the recycling of carbon fiber has always led to a strong degradation of the material. Thanks to a partnership with the automotive industry, however, now the Australian technician has been able to experiment with a new approach.

Normally the process involves the grinding of the composite, with which the carbon fiber is destroyed. Then everything is heated to remove the plastic. Instead in Canberra they do not destroy the fiber and optimize the heating in the furnace. The fibres therefore remain intact and the new product made from recycled carbon fiber is much more durable.

The fibers were recycled by pyrolysis while trying to preserve the fiber architecture. The pyrolysis recycling technique is the most marketed for this material. In this process, the polymer matrix undergoes thermal decomposition at high temperatures in an inert atmosphere. This condition allows carbon fibers not to be damaged, making selective removal of the polymer matrix possible. The pyrolysis of the polymer matrix generates a carbonaceous residue (char) that to be removed involves an oxidative process.

In conclusion, the fiber obtained is not yet suitable for building a car, but is much closer to the goal than before. The hope is that it can be improved and used as soon as possible. The industry believes – or hopes so – because carbon is very coveted but also expensive. Being able to recycle it effectively is a mirage in which more than one person is willing to invest.