Valorization of lithium containing slags from pyrometallurgical recycling route of spent lithium-ion batteries: The enrichment of γ-LiAlO2 phase from thermodynamic controlled and modified slags

• The application of the Engineering of Artificial Minerals strategy to the flotation research of lithium-containing battery slag. • The workload required for mineral processing research is reduced by designing slags for easier beneficiation. • Flotation enrichment of the lithium carrier mineral γ-LiAlO 2 phase in the Li 2 O-CaO-Al 2 O 3 -SiO 2 -MnO slag system is conducted. • Surface property analysis reveals why γ-LiAlO 2 and gehlenite can be separated by flotation. Pyro-metallurgical processing technology is widely used in the spent lithium-ion batteries recycling to recover valuable metals such as cobalt, nickel and copper, while lithium primarily remains in the slag. The effective valorization of slag, especially lithium recovery, constitutes a significant issue in contemporary pyrometallurgical processes due to the paucity of studies. This paper proposes a novel perspective by defining slag as an aggregate of engineered artificial minerals. Thus, not only the parameters of the beneficiation process can be studied to optimize the separation efficiency during treatment, but also the slag can be re-designed to optimize the carrier minerals of target elements and gangue mineral composition in the initial step with thermodynamic tools. In this paper, the engineering of artificial minerals (EnAM) method was applied to the slag design of the Li 2 O-CaO-Al 2 O 3 -SiO 2 -MnO system, and an initial attempt was made to apply EnAM method to the flotation study. A flotation study on enrichment effect of the target phase γ-LiAlO 2 from thermodynamic controlled slags is conducted.