Production of chemical manganese dioxide from lithium ion battery ternary cathodic material by selective oxidative precipitation of manganese

Abstract

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 8mg/dm3 of Al as valuable metals. For selective oxidative precipitation of Mn (II), the leachate was reacted with 1 equivalent of Na 2S2O8 based on the Mn concentration with stirring at 500 rpm at a temperature of 363K for 18000 s. As a result of the reaction, it was confirmed that the majority of Mn was precipitated from the solution. XRD, PSA, TGDTA, 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% Al 2O3, 0.06% S and 0.52% Na2O, an average particle diameter of 10.7 μm, a crystal form of £-MnO2, and a purity of at least 98%. © 2013 The Japan Institute of Metals and Materials.