Researchers have developed a new recycling technique that could transform how the cable industry recovers copper from end-of-life PVC-insulated wires, eliminating the need for toxic chemicals, mechanical stripping, or labor-intensive pre-processing.
The breakthrough, developed by scientists from Sophia University and University of Pavia, uses microwave-induced pyrolysis to separate copper conductors from PVC insulation while minimizing hazardous by-products typically associated with conventional recycling methods.
Copper recovery from electrical cables has become an increasingly important challenge as global demand for electrification, renewable energy infrastructure, electric vehicles, and data centers continues to accelerate. At the same time, recycling PVC-coated cables has traditionally been difficult because separating metal conductors from polymer insulation often requires mechanical shredding, chemical treatment, or thermal processes that can generate harmful emissions.
The new process takes a different approach. Instead of stripping the PVC or shredding the cable, researchers expose intact PVC-insulated cables to microwave radiation inside an inert nitrogen atmosphere. Remarkably, the copper conductor itself acts as a microwave antenna, absorbing the energy and generating localized heating that rapidly decomposes the surrounding PVC insulation.
As the process progresses, the PVC undergoes controlled carbonization and dechlorination, exposing the copper wire while leaving it largely undamaged. Researchers reported that a standard 54-centimeter PVC-insulated power cable could be fully processed within approximately 12 minutes under laboratory conditions.
One of the most significant findings was the absence of many toxic compounds commonly associated with PVC thermal degradation.
According to the researchers, the rapid dechlorination and carbonization process prevented the formation of hazardous substances such as tar, polycyclic aromatic hydrocarbons (PAHs), and dioxins that can occur during uncontrolled burning or conventional thermal treatment of chlorinated plastics. The study also highlights potential opportunities for resource recovery beyond copper.
Researchers suggest that chlorine released during the process could potentially be recovered and reused as hydrochloric acid, while carbonized residues may be suitable for conversion into carbon black or other industrial carbon products. Such pathways could improve the overall circularity of cable recycling operations. For the PVC industry, the development is particularly interesting because it addresses one of the long-standing criticisms surrounding PVC cable recycling. The high chlorine content of PVC has historically complicated thermal recycling processes, requiring additional treatment systems to manage emissions and by-products.
The researchers believe microwave-induced pyrolysis could offer a cleaner alternative, particularly for mixed or difficult-to-process cable waste streams where traditional separation methods become economically challenging.
Global cable demand continues to rise sharply as countries invest in power transmission networks, electrification projects, telecommunications infrastructure, electric mobility, and renewable energy systems. As a result, end-of-life cable volumes are expected to increase significantly over the coming decades, placing greater emphasis on efficient recycling technologies.
Industry analysts note that while the technology remains at the research stage, it represents a promising step toward improving the recovery of both metals and polymer materials from complex electrical waste streams. If successfully scaled, the process could provide cable recyclers with a more efficient route to recover high-value copper while reducing environmental impacts associated with conventional recycling methods, supporting broader circular economy goals across the electrical and plastics industries.