Cite this article as:

Heewon Kang, Muhammad Farhan, Sohwi Park, Li Cai, Allan Gomez-Flores, and Hyunjung Kim, Chelating extraction of critical metals from cathode of end-of-life lithium titanium oxide batteries: Experiments, machine learning and validation, Int. J. Miner. Metall. Mater., (2025). https://doi.org/10.1007/s12613-025-3216-5
Heewon Kang, Muhammad Farhan, Sohwi Park, Li Cai, Allan Gomez-Flores, and Hyunjung Kim, Chelating extraction of critical metals from cathode of end-of-life lithium titanium oxide batteries: Experiments, machine learning and validation, Int. J. Miner. Metall. Mater., (2025). https://doi.org/10.1007/s12613-025-3216-5
引用本文 PDF XML SpringerLink

从废旧锂钛氧化物电池阴极中螯合提取关键金属:实验、机器学习与验证

摘要: 达到使用寿命终点(EoL)的锂离子电池(LIBs)需要回收利用,而非直接丢弃,以循环利用有价值的金属并保护环境。这促使我们研究了使用乙二胺四乙酸二钠(EDTA-2Na)从EoL钛酸锂电池阴极中提取金属。在本研究中,采用正交阵列设计实验,并通过信噪比计算确定最佳条件,即0.50 mol/L EDTA-2Na、pH 6、75°C、180 min、2%矿浆密度和300 r/min,锂、镍、钴和锰的浸出效率分别为97.96%、94.79%、96.45%和98.89%。然后,在95%的置信区间内,使用Pearson相关系数确定变量之间具有统计学意义的相互作用,发现pH值和温度具有显著性。随着pH值的升高,提取效率降低,而随着温度的升高,提取效率提高。使用线性回归进行多输出预测的机器学习拟合并不令人满意,而随机森林回归(RFR)则取得了令人满意的结果。在拟合的RFR上计算置换重要性以确定特征重要性,并确认pH和温度是有影响的变量;不过,时间与浆体密度也值得注意。由于拟合的RFR在额外的验证实验中未能令人满意地预测浸出效率,我们建议增加实验次数并使用额外的拟合模型。另外一项包含初始氧化还原电位(最佳值为33.3 mV)的分析表明,这是最重要的变量,其影响远远超过了其他所有变量。最后,环境评估突出了螯合提取法的优势;然而,经济评估表明仍有改进的空间。

 

Chelating extraction of critical metals from cathode of end-of-life lithium titanium oxide batteries: Experiments, machine learning and validation

Abstract: Lithium-ion batteries (LIBs) that reached their end-of-life (EoL) require recycling, rather than disposal, to recirculate valuable metals and protect the environment. This led us to investigate the extraction of metals from the cathodes of EoL lithium-titanate batteries using ethylenediaminetetraacetic acid disodium (EDTA-2Na). In this work, an orthogonal array was used to design experiments and signal-to-noise calculations were used to define the optimal conditions, which were 0.50 mol/L EDTA-2Na, pH 6, 75°C, 180 min, 2% pulp density, and 300 r/min, resulting in 97.96%, 94.79%, 96.45%, and 98.89% leaching efficiencies for Li, Ni, Co, and Mn, respectively. Statistically significant interactions between variables were then identified using Pearson’s correlation at the 95% confidence interval, and the pH and temperature were found to be significant. The extraction efficiency decreased as the pH increased, but increased as the temperature increased. Machine learning fitting using linear regression for multi-output prediction was unsatisfactory, whereas random forest regression (RFR) produced satisfactory results. Permutation importance was computed on the fitted RFR to determine feature importance, and confirmed that the pH and temperature were influential variables; however, the time and pulp density were also noted. As the fitted RFR failed to satisfactorily predict leaching efficiencies in additional validation experiments, we recommend increasing the number of experiments and using additional fitting models. An additional analysis that included the initial oxidation-reduction potential (optimal 33.3 mV) revealed this to be the most important variable, the effect of which largely overshadows those of all the other variables. Finally, an environmental assessment highlighted the benefits of the chelating extraction; however, the economic assessment indicated room for improvement.

 

/

返回文章
返回