Joint recovery of graphite and lithium metal oxides from spent Li-ion batteries by froth flotation

Spent lithium-ion batteries (LIBs) contain critical raw materials that needs to be recirculated in the battery supply chain. In this work, the joint recovery of cathode and anode materials by froth flotation is proposed. Flotation is a water-intensive process, additionally, the water quality affects the flotation efficiency. In prospect of water-saving strategy, the process water characteristic and the effect of process water recirculation are also investigated. In this work, a pyrolyzed black mass(< 100 μm) is used, containing 43.8% C, 2.5% Li, and 39.4% Co, Ni and Mn as metal oxide. After flotation, a graphite recovery of 95% in the O/F product and a metal recovery of 80% in U/F product are achieved. The process water characterization reveals accumulation of Li ions to a potential value, up to 2600 mg/L.