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With the increase in the production and application of lithium-ion batteries, of waste lithium-ion battery processing has become an increasingly pressing issue. In many treatment programs, the the regenerated current research focus is also the most promising programs. It can not only solve a series of environmental problems brought scrap lithium ion battery, but also on the valuable metals to be recovered and recycled in the battery, the effective mitigation of resource constraints. This thesis is based on exploration test for the a waste lithium-ion battery composed features, combined with the actual situation, determine the battery discharge treatment → → mechanical crushing the positive and negative separation → cobalt aluminum separation → → sulfuric acid hydrogen peroxide leaching cobalt lithium precipitation separation wet France process trivalent metal aluminum, copper, cobalt, lithium, etc. is recovered from the waste lithium ion battery. The process is designed to be simple, focusing on the practical application of resource recycling, waste generation, environment-friendly. Specific content and the results obtained are as follows: pretreatment, the single cell machinery is broken, separated from the battery positive and negative cathode material calcined at 450 ° C 2h remove binder PVDF ultrasonic vibration 2min cobalt oxide The lithium successful separation, recycling aluminum from aluminum foil. The negative grade material calcined at 200 ° C 2h, ultrasonic oscillation 2min, the recovery of copper. Lithium cobalt oxide at 400 ° C, 600 ° C, a temperature of 800 ° C heat treatment by XRD and SEM analysis showed that, as the calcination temperature increases, Co3O4 content gradually increase of LiCoO2 particle size and uniform dispersion Ease of leaching. On the positive electrode active material LiCoO2 leaching using sulfuric acid - hydrogen peroxide system, the successful separation of impurities such as acetylene black. Orthogonal experiment results on the basis of single-factor test: drill and lithium leaching rate with increasing temperature, the reaction time of growth, the increase in the concentration of sulfuric acid increased with the increase of the amount of hydrogen peroxide added. Determine the optimum leaching conditions: temperature 80 ° C, time 120min, acid-oxygen ratio of 4:1, the concentration of sulfuric acid 4mol / L, cobalt and lithium leaching rate of 94.3%. Leaching kinetics LiCoO2 by experiments following conclusions: (1) According to the the formula lntc =-mlnc I obtained acidity affect the series m = 0.82, therefore drill leaching reaction speed relationship between the acid concentration can be expressed as: concentration of sulfuric acid leaching of Co2 affect the greater the resulting acid leaching reaction kinetics equation: lntc = 0.82lncH 3.6812 (2) according to the formula available cobalt leaching reaction apparent activation 17.3kJ/mol, the values ??indicate the cobalt leaching reaction control step for the diffusion step. Cobalt and lithium ions in the leaching solution of lithium cobaltate precipitated separation experiments, and compares the direct synthesis method and process network legitimate sink cobalt results, the precipitated α-Co (OH) 2 and β-Co (OH) 2, respectively, and calcined at 800 ° C for 4 hours crystalline cobalt oxide prepared. With a saturated Na2CO3 solution sink at 90 ° C the temperature of the lithium, the prepared lithium carbonate. Found by XRD analysis, sharp diffraction peaks of the cobalt oxide and lithium carbonate product prepared in high purity. Entire experimental design process is simple, high efficiency, recycling thorough, has good application prospects.
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