This study proposed a recycling method for spent batteries by combining supercritical water oxidation and acid-leaching. In supercritical water oxidation process, the cathode material was separated from the electrode plate, and 98% of lithium in the cathode was leached to achieve the separation of lithium from Ni, Co and Mn. Ni, Co and Mn were then leached during the acid leaching process. The effect of solid-liquid ratio, oxidant mass concentration, reaction time and temperature in supercritical process on metal leaching was analyzed. The leaching rate of Ni, Co and Mn was improved by increasing the mass concentration of oxidant and the reaction temperature. The effect of reaction time on metal leaching is related to the mass concentration of oxidant in the solution. Through the control of paraments, the leaching efficiencies of Ni, Co and Mn were significantly improved from 90.4%, 84.7%, 86.4–99.7%, 96.8% and 98.5%.

中文翻译：

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超临界水氧化酸浸回收废旧三元锂离子电池正极材料效果分析


本研究提出了一种结合超临界水氧化和酸浸的废旧电池回收方法。在超临界水氧化过程中，正极材料与极板分离，正极中98%的锂被浸出，实现锂与Ni、Co、Mn的分离。然后在酸浸过程中浸出Ni、Co和Mn。分析了超临界工艺固液比、氧化剂质量浓度、反应时间和温度对金属浸出的影响。通过提高氧化剂质量浓度和反应温度，提高了Ni、Co、Mn的浸出率。反应时间对金属浸出的影响与溶液中氧化剂的质量浓度有关。通过参数控制，Ni、Co、Mn的浸出率显着提高，分别为90.4%、84.7%、86.4~99.7%、96.8%和98.5%。