废弃锂离子电池正极材料酸浸出试验研究

Study on Leaching Cathode Materials of Spent Lithium-ion Batteries

以废弃三星手机锂电池正极活性材料为对象,将其经焙烧预处理后,采用氨基磺酸(NH2SO3H)溶液作为反应浸出剂,研究了不同试验条件下废弃锂电池正极活性材料的浸出行为,并对反应可能的产物和机理进行探索。试验结果表明:正极材料在450℃下焙烧1 h能够与集流体较好地分离,得到活性材料粉末;在酸浓度为0.75 mol/L,还原剂H2O2用量为2%.Vol,温度为80℃,固液比为10 g/L,反应时间为100 min时,钴、锂元素的回收率分别可达到93.05%和97.16%;同时分析可能生成的产物,当反应温度在氨基磺酸水解温度(60℃)以下时,产物为氨基磺酸钴,而超过60℃时,产物为硫酸钴。本研究实现了对废弃锂电池正极材料中的钴元素和锂元素的高效浸出,为进一步纯化分离钴和锂两种有价金属元素提供有利条件。

Taking the cathode active material of the spent LIBs of Samsung mobile phone as the object,after calcination pretreatment,sulfamic acid(NH2SO3H)liquor was used as the reaction leaching agent.The leaching behavior of the cathode active material of spent lithium-ion batteries(LIBs)under different experimental conditions was studied and the possible products and mechanism of the reaction were explored.The experimental results show that the cathode material can be well separated from the current collector by calcination at 450℃ for 1 h to obtain the active material powder.With 0.75 mol/L sulfamic acid and 2% Vol H2O2 as reducing agent 93.05% Co,97.16% Li were leached out from cathode active material in 100 min at 80℃ and a pulp density of 10 g/L.Simultaneously,the product which may be formed is analyzed.When the reaction temperature is below the hydrolysis temperature of sulfamic acid(60℃),the product is cobalt sulfamate,and when it exceeds 60℃,the product is cobalt sulfate.This study realized the efficient leaching of cobalt and lithium in the cathode material of the spent LIBs,which provides favorable conditions for further purification and separation of two valuable metal elements of cobalt and lithium.