The widespread adoption of carbon fiber-reinforced polymers (CFRPs) across high-performance sectors such as aerospace, automotive, wind energy, and construction has significantly increased the global demand for carbon fibers (CFs). However, the energy-intensive production process and growing volume of end-of-life (EoL) CFRP waste present significant environmental and economic challenges. This review offers a comprehensive analysis of the state of the art in carbon fiber recycling, focusing on the reclamation, remanufacturing, and reuse of recycled carbon fibers (rCFs) to support a sustainable circular economy. These waste streams are projected to grow substantially, driven by the decommissioning of wind turbines and aircraft. The valuable fibers are lost in traditional waste management practices, such as landfilling and incineration. Landfilling is also detrimental to the environment and unsustainable. Hence, recovering CFs through recycling is essential for minimizing environmental impacts and preserving material value. This review presents a comprehensive assessment of recycling technologies, including mechanical, thermal, chemical, and emerging methods. Each technique is assessed based on quantified fiber retention, energy efficiency, scalability, and technological readiness. The study further explores remanufacturing technologies for rCFs, detailing their transformation into intermediate forms suitable for reuse. The alignment of discontinuous fibers is critical for maximizing mechanical performance. Analytical and numerical modeling tools applied to predict fiber orientation, alignment efficiency, and composite behavior are included. In addition to technical insights, the article integrates economic viability, quality assurance, and life cycle assessment (LCA) to evaluate environmental performance, supporting market acceptance and regulatory compliance by quantifying the sustainability advantages of rCFs.
Sántha et al. (Thu,) studied this question.