New process promises greener, more efficient carbon fiber recycling
While it is already possible to recycle carbon fiber, the material is often simply ground up, or broken down using high temperatures and harsh chemicals – the latter of which are difficult to safely dispose of. Additionally, the carbon strands themselves may be damaged in the process, plus the polymer resin which is used to laminate them together can't be reclaimed. Scientists at Washington State University, however, have developed a process that they say doesn't have any of those drawbacks.
Created by a team led by Prof. Jinwen Zhang, the technique involves immersing waste pieces of carbon fiber in a solution made up of "mild acids" and liquid ethanol.
When heated to a relatively low temperature (200 ºC/392 ºF) , the ethanol causes the resin to expand. This allows the acids to get into it, breaking the carbon-nitrogen bonds that hold it solid. It breaks down into a liquid as a result, freeing up the carbon strands for reclamation and subsequent reuse. The resin can also be reclaimed and reused.
The scientists have filed for a patent, and are now looking into commercializing the technique. A somewhat similar process is being developed at Georgia Tech.
A paper on the research was recently published in the journal Polymer Degradation and Stability.
Source: Washington State University