Production of Chemical Manganese Dioxide from Lithium Ion Battery Ternary Cathodic Material by Selective Oxidative Precipitation of Manganese

抄録

We have conducted studies to produce chemical manganese dioxides (CMDs) from ternary cathodic materials by oxidative precipitation. In this study, a cathodic material was concentrated by pretreatment and leached with sulfuric acid to recover 1 L of a leachate containing 22.0 g/dm³ of Co, 21.6 g/dm³ of Mn, 24.2 g/dm³ of Ni, 9.5 g/dm³ of Li and 8 mg/dm³ of Al as valuable metals. For selective oxidative precipitation of Mn (II), the leachate was reacted with 1 equivalent of Na₂S₂O₈ based on the Mn concentration with stirring at 500 rpm at a temperature of 363 K for 18000 s. As a result of the reaction, it was confirmed that the majority of Mn was precipitated from the solution. XRD, PSA, TG–DTA, LECO and ICP analyses were performed to characterize the precipitate. The analytical results revealed the production of a chemical manganese dioxide (CMD) having a chemical composition of 84.60% MnO, 1.40% Co₃O₄, 0.11% Li₂O, 0.25% NiO, 0.02% Al₂O₃, 0.06% S and 0.52% Na₂O, an average particle diameter of 10.7 µm, a crystal form of γ-MnO₂, and a purity of at least 98%.