Optimizations of polyester degradation process of waste copper wire for the application of Cu recycling

Abstract

Recycling of waste copper wire (WCW) has attracted much attention as waste has a huge negative impact on the natural environment. In this study, easy, low cost, and highly efficient technique for recycling copper materials from polymer-coated copper wire was developed using induction heating furnace. Polyester layer on the surface of WCW has been analyzed using FTIR (Fourier Transform Infrared) spectroscopy, Differential Scanning Calorimetry, and Dynamic Thermogravimetric Analysis. As a result, it was confirmed that the polymer coated on the Cu wire, was found to be indeed polyester. A voltage ranging from 562 to 969 V was applied to polymer-coated WCW using induction furnace to remove the coated polymer layer completely from the surface of WCW. FTIR and NMR (Nuclear magnetic resonance) spectroscopy analyses were performed to investigate degradation mechanism of polyester. After applying 969 V, FTIR spectra showed no significant peak for polyester indicating complete removal. Based on this FTIR and NMR analyses, authors assume that, unsaturated aliphatic hydrocarbons, polycyclic aromatic hydrocarbons, benzene, and ethylene are remained with Ash on the Cu wires as final products. Therefore, Cu recycling was successfully done by removing polyester completely at applied voltage of 969 V. POLYM. ENG. SCI., 54:607-615, 2014. (c) 2013 Society of Plastics Engineers