Abstract:The valuable metals in waste lithium ion battery cathode materials were leached applying methanesulfonic acid as leaching agent and ascorbic acid as reductant and leaching agent. Effects of methanesulfonic acid concentration, ascorbic acid concentration, ratio of solid to liquid, reaction temperature, and reaction time on leaching rate of Li, Ni, Co and Mn were explored. The results show that the leaching rate of Li, Ni, Co and Mn is 99.74%, 93.47%, 97.16% and 96.52% respectively under the conditions including methanesulfonic acid concentration of 0.6 mol/L, ascorbic acid concentration of 0.1 mol/L, ratio of solid to liquid of 20 g/L, reaction temperature of 40 ℃, and reaction time of 10 min. The shrinkage unreacted core model was used to fit the kinetic data of metal leaching. The apparent activation energy of Li, Ni, Co and Mn is 35.74, 48.37, 36.81, and 37.85 kJ/mol, respectively. The degree of metal leaching is Li > Co > Mn > Ni.