摘要
为了高值回收利用磷酸铁锂电池废料提锂后的尾渣,本文对其开展了盐酸溶解过程条件优化及浸出动力学研究,重点研究了盐酸浓度、固液比和浸出时间等条件对提锂尾渣溶解效果的影响,并考察了主要成分磷酸铁在盐酸溶液中漫出的动力学。结果表明,在盐酸浓度3mol/L、液固体积质量比15mL/g、反应时间4h、浸出温度30℃条件下,提锂尾渣的溶解率达到92.4%。磷酸铁在盐酸中的浸出过程符合无固态产物层的收缩核模型,表观活化能为25.45kJ/mol,浸出过程受内扩散控制。浸出液采用沉淀法制备磷酸铁粉体,产品XRD图谱与磷酸铁标准图谱匹配良好,且EDS图谱显示P、Fe、O分布均匀,判断制备的粉体为磷酸铁,其中铁磷摩尔比为0.97,其他元素含量稀少,符合电池级磷酸铁行业标准,可用于电池生产。
Aiming at the recycling with high value of the lithium-extracted tailings from lithium iron phosphate battery waste,dissolution process conditions of the lithium-extracted tailings with hydrochloric acid were optimized and leaching kinetics was studied.The effects of hydrochloric acid concentration,solid-toliquid ratio and leaching time on the dissolution efficiency of the lithium-extracted tailings were mainly studied,and the leaching kinetics of the main component iron phosphate in hydrochloric acid solution was investigated.The results show that under the conditions of hydrochloric acid concentration 3 mol/L,liquidsolid volume-to-mass ratio 15 mL/g,reaction time 4 h and leaching temperature 30℃,the dissolution rate of lithium-extracted tailings reaches 92.4%.The leaching process of iron phosphate in hydrochloric acid conforms to the shrinking core model without a solid product layer,with an apparent activation energy of 25.45 kJ/mol,representing that the leaching process is controlled by internal diffusion.The iron phosphate powder was prepared by precipitation of the leaching solution.The XRD pattern of the product matches well with the standard pattern of iron phosphate,and its EDS pattern shows that P,Fe and O are evenly distributed.Therefore,the prepared powder is judged to be iron phosphate,its iron-phosphorus molar ratio is 0.97 and the content of other elements is scarce,which meets the industry standard of battery-grade iron phosphate and can be used in battery production.
作者
刘庆生
喻修远
肖浩
刘嘉铭
邱廷省
LIU Qing-sheng;YU Xiu-yuan;XIAO Hao;LIU Jia-ming;QIU Ting-sheng(Department of Materials and Metallurgy Chemistry,Jiangxi University of Science and Technology.Ganzhou 341000,China;School of Resources and Environment,Jiangxi University of Science and Technology,Ganzhou 341000,China)
出处
《稀有金属与硬质合金》
CAS
CSCD
北大核心
2022年第4期17-23,38,共8页
Rare Metals and Cemented Carbides
基金
国家重点研发计划项目(2018YFC1903400)。
关键词
磷酸铁锂电池废料
提锂尾渣
盐酸浸出
工艺条件优化
动力学
磷酸铁
回收
lithium iron phosphate battery waste
lithium-extracted tailing
leaching with hydrochloric acid
process condition optimization
kinetics
iron phosphate
recovery
