废弃锂离子电池富钴产物焙烧提纯研究

Cobalt Enrichment from Spent Lithium-Ion Batteries by Roasting Process

在800℃下对从废弃锂离子电池回收的-0.25mm富钴粉体进行焙烧提纯,通过X射线衍射仪(XRD)、扫描电子显微镜(SEM)、X射线荧光光谱仪(XRF)分析了-0.25mm富钴粉体焙烧前后的物相组成、颗粒形貌、元素组成变化;并通过硫酸双氧水浸出体系测试了焙烧对后续浸出的影响。结果表明,焙烧可有效去除富钴粉体中的有机物,实现钴的初步提纯,钴含量从29.57%提高至52.36%;焙烧过程中,有机物被全部去除,烧失量为36.14%。部分LiCoO_2转变为变为难浸出的Co_3O_4形式,焙烧条件需要进一步优化控制,减少Co_3O_4的产生。

Cobalt enriched crushed products of spent lithium-ion batteries with particle size of -0.25 mm were purified by roasting at 800℃. Phase analysis, elemental analysis, and micro-morphology analysis of samples before and after roasting were compared by XRD, XRF and SEM. Leachability of roasted products was tested by H2 SO4 and H2O2 leaching solution. The results show that organic mass can be totally removed by roasting, and cobalt content rises from 29.57% to 52.36% with mass loss rate of 36.14%.During roasting process, parts of LiCoO2 change into Co3O4, which is very difficult to be leached. Therefore, optimal control of roasting atmosphere and conditions is necessary to avoid generation of Co3O4.