Macroscopic Depolymerization of Covalent Polymer Matrices via Continuous-Flow Catalyst-Assisted Sonochemistry

The global remediation of synthetic polymers (e.g., PET, HDPE, PFAS) is heavily constrained by the extreme thermodynamic requirements and toxic emissions of thermal incineration. This paper proposes a highly scalable, ambient-temperature alternative utilizing sub-MHz catalyst-assisted sonochemistry. To overcome the scalability and regulatory limitations of classical batch sonochemistry, we propose a continuous-flow acoustic vortex reactor utilizing externally mounted titanium waveguides and a magnetically recoverable Fe3O4@TiO2 core-shell catalyst. Furthermore, the reactor utilizes a highly cross-linked polyurethane-urea elastomeric liner to entirely mitigate cavitation erosion and abrasive material degradation. By subjecting this continuous aqueous suspension to a localized 432 kHz acoustic field, we induce resonant mechano-chemical cleavage. This continuous conversion of municipal synthetic waste into recoverable hydrogen gas (H2) and solid graphite strictly adheres to EPA TSCA guidelines and OSHA noise exposure limits, transitioning global waste management into a net-zero, high-yield green-energy extraction model.