Ball milling preparation of spent graphite supported zero-valent iron-copper to degrade tetracycline in water

In this study, graphite and copper from spent LIBs were used to prepare graphite supported zero-valent iron-copper (ZVI-Cu/G) by ball milling, to improve the reactivity of ZVI. The structure, composition, morphology, and properties of ZVI-Cu/G were fully analyzed. The removal performances of tetracycline by ZVI-Cu/G were tested under different reaction conditions. Graphite and copper improve the dispersion, specific surface area and reactivity of the material. Operational factors, material dosage of 1 g/L, initial pH of 3, temperature of 25 °C, and H₂O₂ concentration of 2 mM, contribute to the best tetracycline removal rate, being 100% in 30 min for 30 mg/L tetracycline solution. The reaction data fits a pseudo first-order model. Tetracycline removal rate was as high as 90% even in the 3rd round of reuse. This study reports a novel ZVI material with high tetracycline removal rate.