Recyclable separation and recovery of carbon fibers from CFRP composites: Optimization and mechanism

Chemical swelling and electrochemical oxidation are combined to realize the separation and recovery of carbon fibers from carbon fiber-reinforced plastic (CFRP) in dimethyl sulfoxide (DMSO) at normal temperature and pressure. The results showed that the depolymerization rate of epoxy resin in CFRP increased with increasing ammonium acetate concentration and current density, and the influence of the current density was more significant than that of the concentration. Microscopic analysis showed that the recycled carbon fibers had few residual resin on their surfaces and mild electrochemical oxidation etching, and recycled carbon fiber monofilament achieved a tensile strength and an interfacial shear strength that were 93.55% and 118.76% those of the original fibers.

Automated summary

The combination of chemical swelling and electrochemical oxidation in DMSO at normal temperature and pressure successfully achieved the separation and recovery of carbon fibers from CFRP. The depolymerization rate of epoxy resin in CFRP increased with increasing ammonium acetate concentration and current density, with the latter having a more significant influence. The recycled carbon fibers showed few residual resin on their surfaces and achieved a tensile strength and interfacial shear strength close to that of the original fibers.