Recovery of Carbon Fiber Reinforced Polymer via Superheated Steam Pyrolysis: Mechanisms, Properties, and Prospects
The escalating volume of end-of-life carbon fiber reinforced polymer (CFRP) and the high energy consumption and emissions of virgin fiber production necessitate low-carbon recycling technologies. Superheated steam pyrolysis, an emerging method, is systematically reviewed. At 450–500 °C, the synergistic 'hydrothermal-weak oxidation' mechanism enables controlled resin cracking and simultaneous char removal. Key parameters—temperature, oxygen concentration, residence time, and CO2/steam two-step coupling—affect the mechanical, surface, and electrical properties of recycled carbon fiber (rCF). A 'low-temperature, short-duration, micro-oxygen' process retains over 90% tensile strength. Comparison of laboratory, pilot, and industrial setups highlights challenges in exhaust gas treatment, multi-component waste adaptability, and energy integration. Life cycle assessment (LCA) confirms this route reduces energy consumption by ~25% and carbon emissions by ~30% versus landfilling/incineration, offering environmental and economic advantages. Future research should focus on product databases, distributed recycling networks, and unified LCA frameworks to support CFRP closed-loop recycling.