Carbon thermal reduction of waste ternary cathode materials and wet magnetic separation based on Ni/MnO nanocomposite particles

The widespread use of lithium-ion batteries and the increase in the number of new energy electric vehicles have brought more waste batteries to be recycled. In this paper, a new combined process for in-situ recycling of wasted ternary lithium batteries using graphite for carbon thermal reduction with the cathode material under nitrogen atmosphere, after which the nanocomposite particles formed by the reduction products were separated and recovered by wet magnetic separation, has been proposed. The carbon thermal reduction products were Li 2 CO 3 , Ni, Co and MnO, respectively, and Ni and Co could form nanocomposite particles with MnO in the thermal reduction process. The reaction mechanism of the carbon thermal reduction reaction of anode materials and the effects of carbon thermal reduction temperature, wet magnetic separation time and solid-to-liquid ratio on the recovery rate were investigated. The recovery rate of Li, Ni, Co and Mn were 95.57 %, 96.44 %, 94.88 % and 94.98 %, respectively, under the optimum condition of reaction temperature of 650 °C, wet magnetic separation time of 75 min and solid-liquid ratio of 15 g/L, respectively.