机械研磨强化废旧锂电材料的选择性提锂  

Selective extraction of lithium ions from spent electrode materials enhanced by mechanical grinding

作　　者：张光文 姜涛 丁立鑫 刘子孟 袁雪 何亚群[2] ZHANG Guangwen;JIANG Tao;DING Lixin;LIU Zimeng;YUAN Xue;HE Yaqun(School of Environment Science and Spatial Informatics,China University of Mining and Technology,Xuzhou 221116,China;School of Chemical Engineering and Technology,China University of Mining and Technology,Xuzhou 221116,China)

机构地区：[1]中国矿业大学环境与测绘学院,徐州221116 [2]中国矿业大学化工学院,徐州221116

出　　处：《中国有色金属学报》2024年第6期1861-1870,共10页The Chinese Journal of Nonferrous Metals

基　　金：国家自然科学基金资助项目(52104273);江苏省自然科学基金资助项目(BK20200645)。

摘　　要：锂离子选择性提取是废旧锂离子电池资源化的重要环节,本文通过无氧低温热处理-机械研磨-筛分除杂强化混合电极粉料选择性提锂。通过物相、形貌、表面元素化学形态、粒度变化等分析混合粉料选择性优先提锂的强化机制。结果表明:500℃无氧低温热处理脱除有机黏结剂过程中可同步实现部分锂离子迁移析出,湿式机械研磨可实现大颗粒团聚物的解离,并同步实现16.09%锂离子浸出;机械研磨并筛分处理后,混合电极粉料中铝含量由3.25%降为0.63%(质量分数),铜含量由2.75%降为0.48%(质量分数);机械研磨可有效促进石墨与正极材料的还原反应过程,强化电极材料中锂离子的迁移析出。低温焙烧-机械研磨-筛分除杂预处理后,混合电极材料还原焙烧-水浸选择性提锂效率由76.81%提升至86.08%。Selective extraction of lithium ions from electrode materials is an important step in the recycling process of spent lithium-ion batteries.In this study,selective extraction of lithium ions from electrode material derived from spent lithium ion battery was enhanced by low temperature heat treatment-mechanical grindingsieving for impurity removal.Through the phase,morphology,surface element chemical forms and particle size,the enhancing mechanism of selective extraction of lithium from electrode materials by the pretreating process was analyzed.The results show that the migration of partial lithium ion can be realized synchronously during the removal of organic binders at low temperature of 500 ℃ in an oxygen-free atmosphere.Large particle aggregates can be dissociated by wet mechanical grinding while 16.09% of lithium ion can be recycled at the same time.After mechanical grinding and screening,aluminum content in eletrode material decreases from 3.25% to 0.63%(mass fraction) while copper content decreases from 2.75% to 0.48%(mass fraction).In addition,more than 80% of copper and aluminum can be removed in the sieving process.Pretreatment can effectively promote the reduction process between graphite and cathode materials,which can strengthen the migration of lithium ions in electrode materials.After low temperature roasting-mechanical grinding-sieving process,selective extraction efficiency of lithium from electrode materials increase from 76.81% to 86.08%.

关 键 词：废旧锂离子电池 电极材料 还原焙烧 选择性提锂 过程强化 

分 类 号：TD952[矿业工程—选矿]