Dual Roles of Acetic Acid in Wind Turbine Blade Recycling: Mechanistic Insights into Enhanced and Inhibited Decomposition Pathways

Chemical recycling of wind turbine blades (WTBs) offers a sustainable pathway for waste management, potentially recovering high-quality glass fibers under mild conditions. However, current strategies are hindered by low decomposition efficiencies, slow kinetics, and complex byproduct formation. Herein, we propose a low-temperature cascading decomposition strategy that uniquely integrates acetic acid swelling pretreatment with Ru-Triphos catalysis. Mechanistic investigations revealed that whereas acetic acid swelling effectively disrupts the dense three-dimensional cross-linked epoxy network, the cascading mode mitigates mass transfer resistance by mechanically separating the resin-wrapped fibers. Nonetheless, a critical compatibility issue was identified: residual acetic acid severely inhibits the catalytic cycle by competing for ligand coordination, necessitating an intermediate acid removal step to restore catalyst activity. Under optimal conditions (160 °C, 72 h; swelling–acid removal–cascade), 99% resin decomposition and 95% bisphenol A (BPA) recovery were achieved. The recovered glass fibers exhibited a tensile strength of 1191.1 MPa (97.7% retention of virgin fibers), representing an 829% improvement compared with pyrolyzed fibers. This work establishes a robust protocol for efficient WTB recycling, offering significant potential for integration into industrial-scale dismantling and catalyst closed-loop systems.