中南大学学报（自然科学版）2023，Vol.54Issue(12)：4611-4619,9.DOI:10.11817/j.issn.1672-7207.2023.12.001
碳热还原-多段浸提强化废旧锂电材料选择性提锂研究
Selective recovery of lithium from spent electrode materials by carbothermal reduction combined with multistage leaching
摘要
Abstract
Efficiency of selective lithium extraction was low due to the complex composition of electrode materials derived from the mechanical crushing process of spent lithium-ion batteries.An efficient selective lithium extraction method of reduction roasting combined with multi-stage extraction was proposed.Firstly,the anode material in the mixed powder was used as the roasting reductant to achieve the efficient reduction of cathode material and the transformation of lithium ion.Secondly,high selective leaching efficiency of lithium ions was realized through the combination of water leaching and alkali leaching,and the aluminum ions in alkaline leaching solution were removed by precipitation with pH adjustment method.Finally,aerobic roasting combined with water leaching was employed to recover the lithium ions in the precipitates.The results show that the carbon powder and residual aluminum foil in the mixture affect the reduction roasting process at 700℃.After reduction roasting,the chemical states of lithium ions in electrode materials include water-soluble Li2CO3,alkali-soluble LiAlO2 and acid-soluble LiF.Water-leaching method can recover 75.6%of water-soluble lithium from electrode materials,while alkali-leaching method can recover 10.8%of alkali-soluble lithium from electrode materials.The efficient precipitation and removal of aluminum ions in lithium solution can be achieved at the pH of 6.The lithium ions in the aluminum precipitate can form soluble lithium salt in the aerobic roasting process,while aluminum can be converted into water insoluble Al2O3,and the recovery of 95%lithium ions in the aluminum precipitate can be achieved.The selective extraction of lithium ions from the electrode materials can be achieved by reduction roasting-water leaching-alkaline leaching,and the lithium ions contained in the aluminum precipitate can be efficiently recovered by aerobic roasting-water leaching.The selective extraction efficiency of lithium ions from the spent electrode materials can reach 86.21%after carbothermic reduction-multi-stage leaching.关键词
废旧锂离子电池/电极材料/还原焙烧/选择性提锂/多段浸出Key words
spent lithium-ion battery/electrode material/reduction roasting/selective recycle lithium/multistage leaching分类
矿业与冶金引用本文复制引用
袁雪,丁立鑫,刘子孟,姜涛,何亚群,张光文..碳热还原-多段浸提强化废旧锂电材料选择性提锂研究[J].中南大学学报（自然科学版）,2023,54(12):4611-4619,9.基金项目
国家自然科学基金资助项目(52104273) （52104273）
江苏省自然科学基金资助项目(BK20200645)(Project(52104273)supported by the National Natural Science Foundation of China （BK20200645）
Project(BK20200645)supported by Natural Science Foundation of Jiangsu Province) （BK20200645）
