Researchers develop advanced recycling method for carbon fibres

Full article issued by The University of Sydney.

ARC-supported researchers from The University of Sydney’s School of Civil Engineering have developed an optimised method for recycling carbon fibre reinforced polymer (CFRP) composites that could be up to 70 percent cheaper and lead to a 90-95 percent reduction in CO2 emissions, compared to standard manufacturing.

CRFP composites are present in products such as wind turbines, aeroplane parts, and everyday technology such as laptops and mobile phones, but are typically disposed of in landfills or by incineration, which pose significant threats to both the environment and public health. 

'Globally and in Australia there has been a march towards better recycling processes, however there is often the belief that a material can be recycled an infinite amount of times – this simply isn’t the case. Most recycling processes diminish mechanical or physical properties of materials,' says the study’s lead researcher and ARC Discovery Early Career Research Awardee (DECRA), Dr Ali Hadigheh.

The research team used a two-phased, optimised process to break down and recycle carbon fibre. The first step uses heat to char the materials, while the second step uses oxidation at high temperatures to remove this char. To ensure a high quality recovery and economic efficiency, the process was guided by analysing the optimal energy required to initiate a chemical reaction in the composite, and separate carbon fibres from the surrounding resin matrix.

'The 2016 Australian National Waste Report concludes that the use of composite materials is creating future challenges to recycling. Plainly put, if we do not develop efficient and cost-effective methods to recycle carbon fibre composites, we risk damaging the environment significantly,' says Dr Hadigheh.

'What makes our method so successful is that we have added specific parameters – such as temperature, heating rate, atmosphere or time spent being oxidised and heated – that preserve the functionality of carbon fibre.'

 

A composite Airbus A350 with carbon fibre themed livery. Image Credit: Wikipedia (CC BY-SA 2.0).