Fast recovery process of carbon fibers from waste carbon fibers-reinforced thermoset plastics

In this work, we report a fast recycling process for carbon fiber-reinforced thermosetting resin matrix composites, to obtain recycled carbon fibers. Steam (H2O) was selected as an oxidant to decompose the resin of the composites. The recycling reaction temperature and time were set in the range of 600-800 degrees C and 60 min, respectively. The recovery yield, surface morphologies, and mechanical properties including tensile strength and modulus of the recovered fibers were measured to evaluate the recycling efficiency. Microstructural properties of the recycled fiber were observed by X-ray studies, and the correlation of mechanical properties of the fibers with crystallite size and distribution was also evaluated. In conclusion, the carbon fibers were successfully recycled, while retaining 65% and 100% of the fibers' original tensile strength and modulus, respectively. 100% recovery yield was achieved in 60 min of decomposition time and 140 min of total process time.