Preparation Of Ultrafine Co₃O₄Powder Materials Using Waste Lithium-ion Battery

With the development of national economy, and the improvement of people’s materiallife level, mobile phone has become an essential communication tool in our life. Mobilephone batteries contain precious cobalt element, average each of cell phone battery contents28%of cobalt. With a large number of cell phone upgraded and abandoned, a lot of cobaltresources were wasting. It is particularly urgent to recycle cobalt in waste battery.In this paper, organic solvent was used under the condition of ultrasonic to separatelithium cobalt oxides and aluminum foil, dimethyl formamide could completely dissolvedbinder on the aluminum foil at60℃, and100%Al is recycled. The results show that94.77%leaching efficiency can be achieved under optimum conditions of solid/liquid ratio1:100,3.0mol/LH2SO4,3ml/gH2O2, leaching time is50min and leaching temperature is65℃.Chemical precipitation was used to remove the impurity in the leach liquor, The results showthat Fe3+in the solution at pH=4.0can completely precipitation, the Co can be controlledunder1%loss rate; Cu2+and Al3+in the pH=5.5can be completely precipitation, the loss rateof Co close to5%. The removal of impurities from the leach liquor can be achieved byadjusting the pH to around5.5. Needle-like cobalt oxalate powder was obtained underprocessing parameters followed: T=50℃, pH=1.8, n((NH4)2C2O4):n(Co)=1.25:1, the powderis evenly distributed by laser particle size instrument measurement, the length is2μm andlength to diameter ratio of the needle-like cobalt oxalate powder is very high, the precursor isorthorhombic system. Co3O4powder can be received by thermal decomposing of cobaltoxalate, by XRD analysis product is cubic spinel structure, the heritage can be found by theSEM examination and length to diameter ratio of the Co3O4is very high, the powder is evenlydistributed by laser particle size instrument measurement.A set of complete recovery of cobalt aluminum membrane process is formed byrecycling cobalt element, the economic benefits is estimated according to the flow chart, andthe recycling process has many economic benefits without considering the costs of labor.