Copper-catalyzed VOCs formation and combustion control during pyrolysis of waste polyester-imide enameled wires.

The emission of volatile organic compounds (VOCs) during the pyrolysis of waste enameled wires poses a significant challenge to green and sustainable recycling. This study systematically investigates the formation mechanisms and mitigation strategies for VOCs during the pyrolysis of waste polyester-imide enameled wires, with a focus on the catalytic role of copper. Combining thermogravimetric analysis, PY-GC/MS, and density functional theory (DFT) calculations, we demonstrate that VOCs emissions primarily occur between 500-700 °C, generating alkanes, alkenes, and aromatic compounds. DFT reveals that copper modifies the electronic structure of the organic film, reducing the HOMO-LUMO energy gap and significantly accelerating pyrolysis reactivity, thereby promoting aromatic compound formation. To address this issue, an optimized combustion strategy (600 °C, excess air ratio of 1.10, furnace pressure of -0.04 MPa) was developed, which achieved a 95 % reduction in VOCs emissions compared to conventional pyrolysis. Mechanistic studies confirm that combustion effectively oxidizes most VOCs into CO2 and H2O, leaving only trace aldehyde residues. These findings not only elucidate the catalytic pathways of copper in VOCs formation but also provide a practical and efficient approach for VOCs suppression, advancing the development of environmentally friendly recycling technologies for electronic waste.