Room temperature acid extraction of Co from LiCo0.2Ni0.8O2 scrap by a mechanochemical treatment

Room temperature extraction of valuable substances from LiCo0.2Ni0.8O2 scrap containing polyvinylidene fluoride (PVDF) has been carried out using 1 N HNO3 solution after mechanochemical (MC) treatment by a planetary mill with and without Al2O3 powder. Crystalline LiCo0.2Ni0.8O2 in the scrap was pulverized and became amorphous by MC treatment for 60 and 240 min, respectively, with and without Al2O3 power. This shows that the addition of Al2O3 is very effective for MC treatment. Accordingly, Co as well as Ni and Li were extracted at a high yield of more than 90% from the amorphous scrap sample. About 1% of fluorine in the PVDF was dissolved in the filtrate when the Al2O3 powder was added to the scrap during the MC treatment, while no fluorine was detected in the filtrate obtained from the ground scrap sample without Al2O3 powder.