摘要
开展了含多种杂质的废旧磷酸铁锂正极粉提锂工作,重点探讨了铝、铜、氟三种元素含量对组分浸出规律的影响,并阐明浸出机制。结果表明,铜含量在0.1%~2.5%时对各组分的浸出基本无影响,Li、Fe的浸出率稳定在98.9%和0.69%。随着Al含量由0.3%提高至1.5%,Li的浸出率不变,但Fe组分的浸出率同步增大至10.61%。Li浸出率随着氟含量(0.21%~3.17%)的增大而下降至94.1%,同时Fe浸出率随其同步提高至8.97%。热力学分析和SEM等结果表明,强还原性的Al与FePO_(4)反应生成高溶解度的Fe^(2+),F^(−)分别络合Li^(+)/Al^(3+)或FePO_(4)生成难溶性Li_(3)AlF_(6)和可溶性的FeF_(3)。
The delithiation of impurities-containing spent lithium iron phosphate cathode power was carried out,and the influence of the content of aluminum,copper or fluorine on the leaching behavior of each component were comprehensively investigated.The leaching mechanism was also clarified.Results indicate that the copper(0.1%~2.5%)has no influence on the leaching rate of lithium iron phosphate.Besides,the increase of aluminum(0.3%~1.5%)also has no effect on the leaching rate of Li,while is beneficial for the leaching rate of Fe,reaching to 10.61%.It is observed that the higher content of fluorine(0.21%~3.17%)would result in lower leaching rate of Li(94.1%)and higher leaching constant of Fe(8.97%).The thermodynamic analysis as well as SEM characterization demonstrate that the reaction of high reductive aluminum with FePO_(4) would produce the high solubility of Fe^(2+).In addition,the treatment of F−with Li^(+)/Al^(3+)and the reaction of F^(−)with FePO_(4) could produce the insoluble Li_(3)AlF_(6) and soluble FeF_(3),respectively.
作者
李立平
邱焕彬
LI Liping;QIU Huanbin(Guangdong Guanghua Sci-tech Co.,Ltd.,Shantou 515000,China)
出处
《广州化学》
2025年第4期75-79,共5页
Guangzhou Chemistry
基金
国家重点研发计划青年科学家项目(2022YFC2906000)。
关键词
废旧磷酸铁锂正极粉
铝
铜
氟
浸出规律
浸出机制
spent lithium iron phosphate cathode power
aluminum
copper
fluorine
leaching law
leaching mechanism
作者简介
李立平(1991-),男,广东人,博士,工程师,主要从事金属盐开发与锂电回收工作。1543851723@qq.com。
