Scientists give aircraft composite waste a second life

Researchers from the National University of Singapore have devised a method to convert waste from advanced composites used in aircraft and other high-performance structures into useful aerogels. Led by Associate Professor Duong Hai Minh, the study, published in Waste Management, demonstrates how to transform both the carbon fiber and epoxy components of these composites into materials with potential applications in insulation, sound absorption, and oil spill cleanup.

Traditional recycling methods often focus on recovering carbon fibers, discarding or treating epoxy resins as low-value byproducts. However, Duong's team took a novel approach by mechanically processing the composite waste into a powder and short fiber mixture, combining it with a cellulose-based binder, and freeze-drying the result into a sponge-like aerogel.

This process preserves the tiny, connected pores within the aerogel structure, which is largely composed of air, making it an excellent insulator. Laboratory tests showed the aerogels had low thermal conductivity, indicating their potential as lightweight insulation materials. Additionally, the aerogels demonstrated effective sound absorption, promising applications in noise control.

Their water-repellent treatment also allowed the materials to absorb significant amounts of oil, suggesting their utility in oil spill remediation and oil-water separation. Crucially, the aerogels proved non-toxic to fibroblast cells, supporting further exploration of their potential uses in human health and environmental applications.

The researchers are now seeking partnerships with industry leaders in aerospace, advanced materials, manufacturing, and waste management to scale up the technology and evaluate its industrial viability.