| Its high cost of lithium-ion batteries, lightweight, easy to carry, etc., in the life of the field of electronics have occupied a high position, which also has broad application prospects in future electronics. With the number of lithium-ion batteries in the electronics field ever soared, its limited life expectancy, resulting in a large number of lithium-ion batteries to be eliminated, if not timely and reasonable governance, people’s living environment will bring great threaten. Since lithium-ion batteries have a relatively high content of valuable metals, cobalt resources in our relatively short, and not a lot of mineral resources development situation, the failure of lithium-ion batteries for recycling, not only will help reduce environmental pollution problems also help alleviate supply and demand of cobalt resources.This article discusses the status of research on the failure of lithium ion recycling at home and abroad, there are mainly two methods, fire and wet. LiCoO2in an acidic solution based on chemical dissolution properties hydrometallurgical techniques developed despite the advantages of high metal recovery, but are difficult to avoid leaching of the polluting gases produced serious drawbacks which limit the practical application of the technology. Currently obvious defects research has been carried out on a comprehensive understanding of the physical and chemical properties of LiCoO2presence limits the waste of valuable metal recovery LiCoO2new process design and development. This article is mainly used LiCoO2with NaHSO4or Na2S2O7, etc. according to certain molar ratio, calcine product after acidic phase was analyzed by XRD, but the process some of the basic problems remain unclear. In this study, the chemical form and the elements of the acidic elements in the roasting process migration control mechanism directed migration scientific questions, using TG-DSC-MS, XRD and SEM-EDS and other research tools to reveal elements of the roasting process in which the acidic states of matter, physical and chemical characteristics of the compound type and escaping gas composition, morphology and elemental products change with temperature changes in the product particles, such as distribution and distribution. Calcined mixed findings showed that:(1) the LiCoO2with NaHSO4. H2O in a molar mixing ratio of1:3, the results showed that:LiCoO2with NaHSCO4. NaHSO4first reaction stage loss of crystal water, when the temperature rises, NaHSCO4also physically adsorbed water loss, when the temperature reaches about600℃, with sulfur and oxygen overflow. Detected by XRD analysis, lithium element mainly LiNa (SO4) form, cobalt is COSO4.H2O and Na2Co(SO4)2is present in the form of low temperatures, when the temperature is relatively elevated, is based Na6Co (SO4)4forms exist, as the temperature increases the particle size of the product morphology is reduced continuously by the lumps into scaly, Li, Co, S, O dispersed state of the element present in the product distribution.(2) the uniformity of LiCoO2with Na2S2O7molar mixing ratio of1:1.5, TG-DSC-MS results show that the process of showing a TG weight loss of three steps, obviously corresponding to the two endothermic peaks in the first stage the main stage is Na2S2O7lost physically adsorbed water, the second stage is obviously sulfur dioxide gas spill. By XRD results showed: Li elements mainly LiNa (SO4) form, and Co elements as the temperature rises mainly in the form Na6Co (SO4)4exists, at low temperatures, the morphology of the product was not rules, mainly lumps mainly, but also some aggregates, as the temperature rises, more and more rules morphology of the products, showing scaly, Li, Co, S, O elements showing diffuse state distribution in the product. |
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