Recovery of copper and plastics from discarded cable waste using vibratory separation: Experimental optimization, statistical modeling, and process evaluation

The recycling of discarded electrical cables is important for recovering valuable copper and reducing the environmental burden of polymeric insulation waste. This study investigates a laboratory-scale vibratory separation system for recovering copper and plastic fractions from mechanically crushed cable waste. The objective was to evaluate the effects of motor speed and table inclination on separation efficiency and to develop statistical models for recovery and purity responses. Controlled 50/50 copper–plastic mixtures were prepared from pre-processed cable waste to ensure reproducible laboratory conditions, while recognizing that this feed is simplified compared with variable industrial cable-waste streams. Tests were conducted at motor speeds of 700–1200 rpm and four inclination configurations based on transverse tilt angle (α) and longitudinal tilt angle (β). The best performance within the tested experimental domain was obtained at α = 8°, β = 0°, and 1000 rpm, yielding copper recovery of 96.63% with 97.67% purity, and plastic recovery of 97.70% with 96.73% purity. Response surface regression models were developed to describe the influence of operating parameters on separation performance. Statistical analysis showed that motor speed and its quadratic term were the dominant factors, while the copper recovery model showed the strongest predictive performance. The results indicate that vibratory separation is a promising dry mechanical approach for copper–plastic separation under controlled laboratory conditions. However, further validation using real industrial feed streams, continuous feeding, dynamic vibration measurements, and energy-consumption analysis is required before broader industrial application can be confirmed.