WASTE PVC-ASSISTED CHLORINATION ROASTING FOR EFFICIENT RECOVERY OF CATHODE MATERIALS FROM WASTE LITHIUM-ION BATTERIES

Using waste PVC as a chlorinating agent, through chlorination roasting and low-temperature water leaching compound, we effectively improved the leaching efficiency of cobalt and lithium in the anode material LiCoO₂ of the waste lithium-ion battery. The effects of calcination temperature, chlorinating agent and cathode material LiCoO₂ material ratio, calcination time and other parameters on the leaching rate of cobalt and lithium were systematically studied. The research results showed that under the conditions of calcination temperature of 500℃, material ratio of 5:1, and calcination time of 120 min, the leaching rate of metallic cobalt reached more 95% above and the leaching rate of metallic lithium reached 99% after being immersed in water at 60℃. At the same time, X-ray diffraction(XRD), scanning electron microscope(SEM), and X-ray photoelectron spectroscopy(XPS) were used to characterize the crystal structure and surface morphology of the material before and after calcination, as well as the changes in element valence, and in-depth elucidate the process of chlorination calcination of LiCoO₂, and conversion mechanism and kinetic mechanism of cobalt and lithium. Compared with the traditional wet method, fire method and biometallurgy technology, this recycling technology has lower energy intensity and higher industrial application prospects.