High-quality electrostatic recycling of waste carbon fiber via spark-driven shock waves and Joule heating

The recycling of waste carbon fibers (CF) has emerged as a crucial research area for both environmental protection and economic sustainability. To sufficiently exert the potential and extend the application life cycle of CFs, here we propose an eco-friendly and efficient electrostatic method for rapid recycling of tightly entangled reclaimed carbon fibers (rCFs) by spark-driven disentanglement and depolymerization. Our research indicates that the spark discharge generated by fiber induction under low-voltage conditions can excite the shock waves and Joule heating effects, resulting in the separation of individual rCFs and the removal of surface organic matrix. Furthermore, the constructed electric field can synchronously and continuously orient the dispersed rCFs to form a vertical alignment in a short time with good maneuverability and directionality for reutilization. The results demonstrate that this one-step disentanglement, depolymerization, and alignment method achieves a high-quality recycling process with 100% dispersion efficiency, minimal damage, cost-effectiveness, uniform distribution, upright orientation, and high-speed embedding performance. Our findings reveal the potential of the electrostatic strategy for the high-quality recycling of rCFs, in line with the principles of the circular economy. The proposed method offers broad prospects for application in continuous in-line production and material manufacturing, and is a step towards sustainable and cost-effective CF recycling.