【作者】 张灏；

【导师】 金鑫；

【作者基本信息】 北京化工大学 ， 无机化学， 2007， 硕士

【摘要】 由于锂离子电池能量密度高、质量轻、寿命长、无记忆性,所以现在约有80%便携式电子设备使用锂离子电池。但是继而产生的废旧锂离子电池成为一种钴含量较高的工业垃圾,具有较强毒性,如处理不当可对环境造成污染。与此同时,我国匮乏钴资源,钴储量只有58.3万吨,不足世界总储量的4%。因此如果能够从废旧的锂离子电池废液中回收钴元素,注重其二次利用价值,不仅具有经济效益,而且可以减轻对环境的污染,具有广泛的社会效益,是社会可持续发展的重要要求。锂电池废料的成分为大量的基体材料Al、LiCoO2及少量杂质C、Fe,其中还含有约3%0的Ni。在溶解废料,调节pH值过程中会引入Ca、Mg等杂质元素。由于Ni的含量在5%0以下时并不影响电池性能,而Ca、Mg、Fe杂质的引入会影响电池的储电量,Al杂质在合成过程中影响晶体的生长,因此本研究的主要目是减少Al、Ca、Mg、Fe元素在碳酸钴中的含量及制备粒径合适的碳酸钴及四氧化三钴粉体。本实验采用分步沉淀法分别除去废锂电池液中的铁、铝；吸附沉淀法分别除去钙、镁等杂质；用元素分析仪对回收的钴溶液进行组份分析,结果表明在pH=5时,杂质含量符合电子行业对钴生产的要求。继而采用均匀沉淀法制备得到粉末碳酸钴；将此碳酸钴煅烧得到最终产物四氧化三钴。扫描电镜和粒度分析结果表明,当温度控制在60O℃时,四氧化三钴径分布在7～10μm。研究表明,影响碳酸钴粉与四氧化三钴粉体形状和尺寸的主要因素是合成温度。另外本研究还通过均匀沉淀提纯法从锂离子二次电池中回收得到了与理论含量非常接近、粒径分布均匀、无团聚、堆积密度大的碳酸钴及四氧化三钴粉体。更多还原

【Abstract】 Due to high energy density, low gravity and good performance, Li ion battery has received much attention in recent years and occupies about80%percent in the market of electronic portable devices. However, it should be pointed out that the abandoned battery wastes have become serious problems for the environment, which is poisonous for human being’s health. Even worse, China is lack of Cobalt element, which is indispensable raw material for Li battery. It is important and significant to realize the recycle use of Li battery, which could not only ease the pollution to the environment but also mean much for the sustainable development for a country.Most waste of abandoned Li battery are A1、 LiCoO2, and few are C and Fe elements, among which Ni elements occupies3%o. In the process of solubilization, few purities such as Ca and Mg elements were unexpectedly introduced to the solution. Although the contents of Ni elements lower than5‰has little effect on the performance of Li battery, the existence of Ca, Mg and Al do influence the charge capacity of batteries and structure of crystals. In this paper, we concentrated on the elimination of Al, Ca, Ma and Fe elements and preparation of Cobalt carbonate and Co3O4.The waste elements Fe, Al and Ca, Mg were eliminated from discarded lithium batteries by fractional and adsorption precipitation method respectively. Element analysis results demonstrated that theproducts met with the requirements of electronic standards. Then Powder CoC03was obtained by homogeneous precipitation. Final product Co3O4was then achieved by calcinations. Scanning electron microscopy images and granularity analysis demonstrate particle size of Co3O4ranges from7to10μm at600℃. Our results show that temperature plays predominant role in the shape and size of CoCO3and Co3O4.更多还原