废旧磷酸铁锂电池钠盐焙烧提锂工艺

Lithium Extraction Process from Spent LiFePO_(4) Batteries by Sodium Salt Roasting

废旧锂离子电池的无害化处理和资源化回收是保护环境、节约资源、促进循环经济发展的必然选择。提出了一种钠盐焙烧—常温水浸工艺,用于从废旧磷酸铁锂电池中回收锂。系统研究了硫酸钠添加量、焙烧温度、焙烧时间等对锂选择性浸出的影响,并对焙烧产物进行了XRD和SEM表征。结果表明,在硫酸钠与磷酸铁锂正极粉质量比为1.6、焙烧温度650℃、焙烧时间2.0 h、水浸时间15 min的条件下,锂的浸出率达到96.81%,回收得到的硫酸锂产品纯度达到97.36%。与传统方法相比,该工艺具有不使用强酸、高效锂铁分离、回收过程简便等优势,具备广泛的工业应用前景。

The harmless treatment and resource recycling of spent lithium-ion batteries is an inevitable choice to protect the environment,save resources,and promote the development of circular economy.A process of sodium salt roasting and water leaching at room temperature was proposed to recover lithium from spent LiFePO_(4) batteries.The effects of sodium sulfate addition,roasting temperature,and roasting time on the selective leaching of lithium were systematically studied,and the roasted products were characterized by XRD and SEM.The results show that under the conditions of mass ratio of sodium sulfate to LiFePO_(4) cathode powder of 1.6,roasting temperature of 650℃,water leaching time of 15 minutes,and roasting time of two hours,the lithium leaching rate is 96.81%,and the purity of the recovered lithium sulfate product is 97.36%.Compared with traditional methods,this process has the advantages of no use of strong acid,high efficiency separation of lithium iron and simple recovery process,and has broad industrial application prospects.