Impact of pH and collector concentration on froth flotation of spent lithium-ion battery materials
Keywords:
LIB, Froth flotation, Graphite, Metal oxide, Recovery efficiencyAbstract
Lithium-ion batteries (LIBs) are widely used in mobile phones and electric vehicles, but their limited lifespan leads to environmental challenges, particularly due to heavy metal waste. Recycling LIBs is essential for reducing pollution and recovering valuable materials from both the anode and cathode. Froth flotation has emerged as a promising technique for separating these materials, though recovery efficiency and optimal conditions remain unclear. Pretreatment is critical for improving recovery, with pyrolysis being effective for removing organic binders like PVDF and CMC, which are commonly used in LIB electrodes. Pyrolysis, performed at 500°C, decomposes binders and recovers valuable cathode materials such as nickel, cobalt, and aluminum. This study investigates the recovery of graphite (anode) and metal oxides (cathode) in froth flotation by varying collector concentrations (850–2500 g/t) and pH levels (4–9). The highest graphite recovery (90.05%) occurred at a collector concentration of 850 g/t, while the metal oxide recovery was 25.5%. Lower collector concentrations resulted in incomplete anode particle coverage, while higher concentrations reduced selectivity. At pH 7, the best recovery was achieved, with graphite recovery of 94.61% and metal oxide recovery of 24.14%. These findings highlight the importance of pyrolysis pretreatment for binder removal and provide insights into optimizing flotation parameters, enhancing the efficiency and sustainability of LIB recycling processes.
References
[1] A. Holzer et al., “A Combined Hydro-Mechanical and Pyrometallurgical Recycling Approach to Recover Valuable Metals from Lithium-Ion Batteries Avoiding Lithium Slagging,” Batteries, vol. 9, no. 1, Jan. 2023, doi: 10.3390/batteries9010015.
[2] S. J. An, J. Li, Y. Sheng, C. Daniel, and D. L. Wood, “Long-Term Lithium-Ion Battery Performance Improvement via Ultraviolet Light Treatment of the Graphite Anode,” J. Electrochem. Soc., vol. 163, no. 14, pp. A2866–A2875, 2016, doi: 10.1149/2.0171614jes.
[3] L. Verdugo, L. Zhang, K. Saito, W. Bruckard, J. Menacho, and A. Hoadley, “Flotation behavior of the most common electrode materials in lithium ion batteries,” Sep. Purif. Technol., vol. 301, Nov. 2022, doi: 10.1016/j.seppur.2022.121885.
[4] Ma Xuesong et al., “The Recycling of Spent Lithium-Ion Batteries: Crucial Flotation for the Separation of Cathode and Anode Materials,” Molecules, vol. 28, no. 4081, pp. 1–20, Feb. 2023, doi: 10.3390/molecules.
[5] P. C. B. W. Mustika et al., “Optimization of Lithium Separation from NCA Leachate Solution: Investigating the Impact of Feed Concentration, Pressure, and Complexing Agent Concentration,” ASEAN J. Chem. Eng., vol. 23, no. 3, pp. 343–359, 2023, doi: 10.22146/ajche.83096.
[6] G. Zhang, Y. He, Y. Feng, H. Wang, and X. Zhu, “Pyrolysis-Ultrasonic-Assisted Flotation Technology for Recovering Graphite and LiCoO2 from Spent Lithium-Ion Batteries,” ACS Sustain. Chem. Eng., vol. 6, no. 8, pp. 10896–10904, Aug. 2018, doi: 10.1021/acssuschemeng.8b02186.
[7] L. Verdugo, L. Zhang, B. Etschmann, W. Bruckard, J. Menacho, and A. Hoadley, “Effect of lithium ion on the separation of electrode materials in spent lithium ion batteries using froth flotation,” Sep. Purif. Technol., vol. 311, Apr. 2023, doi: 10.1016/j.seppur.2023.123241.
[8] A. Zanoletti, E. Carena, C. Ferrara, and E. Bontempi, “A Review of Lithium-Ion Battery Recycling: Technologies, Sustainability, and Open Issues,” Batteries, vol. 10, no. 1, 2024, doi: 10.3390/batteries10010038.
[9] Q. Zhao, K. Sun, X. Wang, Q. Wang, and J. Wang, “Examining green-sustainable approaches for recycling of lithium-ion batteries,” DeCarbon, vol. 3, no. August 2023, p. 100034, 2024, doi: 10.1016/j.decarb.2023.100034.
[10] A. Chagnes and B. Pospiech, “A brief review on hydrometallurgical technologies for recycling spent lithium-ion batteries,” J. Chem. Technol. Biotechnol., vol. 88, no. 7, pp. 1191–1199, 2013, doi: 10.1002/jctb.4053.
[11] P. M. Tembo, C. Dyer, and V. Subramanian, “Lithium-ion battery recycling—a review of the material supply and policy infrastructure,” NPG Asia Mater., vol. 16, no. 1, 2024, doi: 10.1038/s41427-024-00562-8.
[12] W. Mrozik, M. A. Rajaeifar, O. Heidrich, and P. Christensen, “Environmental impacts, pollution sources and pathways of spent lithium-ion batteries,” Energy Environ. Sci., vol. 14, no. 12, pp. 6099–6121, 2021, doi: 10.1039/d1ee00691f.
[13] N. Traore and S. Kelebek, “Characteristics of Spent Lithium Ion Batteries and Their Recycling Potential Using Flotation Separation: A Review,” Mineral Processing and Extractive Metallurgy Review, vol. 44, no. 3. Taylor and Francis Ltd., pp. 231–259, 2023. doi: 10.1080/08827508.2022.2040497.
[14] S. Husin et al., “Recovery of valuable metals from NMC-811 li-ion battery waste with froth flotation and hydrometallurgical extraction,” Eng. Appl. Sci. Res., vol. 51, no. 1, pp. 117–127, Nov. 2024, doi: 10.14456/easr.2024.13.
[15] R. Prakash, S. K. Majumder, and A. Singh, “Flotation technique: Its mechanisms and design parameters.”
[16] F. Larouche et al., “Progress and status of hydrometallurgical and direct recycling of Li-Ion batteries and beyond,” Materials (Basel)., vol. 13, no. 3, 2020, doi: 10.3390/ma13030801.
[17] X. Zhong et al., “Binding mechanisms of PVDF in lithium ion batteries,” Applied Surface Science, vol. 553. 2021. doi: 10.1016/j.apsusc.2021.149564.
[18] L. Qiu and I. Shao, ZiqiangWang, DaxiongWang, FeijunWang, WenjunJWang, “Novel polymer Li-ion binder carboxymethyl cellulose derivative.”
[19] H. Wang, C. Liu, G. Qu, S. Zhou, B. Li, and Y. Wei, “Study on Pyrolysis Pretreatment Characteristics of Spent Lithium-Ion Batteries,” Separations, vol. 10, no. 4, 2023, doi: 10.3390/separations10040259.
[20] D. S. Premathilake, A. B. Botelho Junior, J. A. S. Tenório, D. C. R. Espinosa, and M. Vaccari, “Designing of a Decentralized Pretreatment Line for EOL-LIBs Based on Recent Literature of LIB Recycling for Black Mass,” Metals, vol. 13, no. 2. MDPI, Feb. 01, 2023. doi: 10.3390/met13020374.
[21] R. Efendi, S. Gohari, and S. C. Chelgani, “Surface properties of LiBs’ electrode active materials as key factors for the flotation recycling–A comprehensive review,” Surfaces and Interfaces, vol. 56, no. October 2024, p. 105655, 2025, doi: 10.1016/j.surfin.2024.105655.
[22] M. Heber, K. Hofmann, and C. Hess, “Raman Diagnostics of Cathode Materials for Li-Ion Batteries Using Multi-Wavelength Excitation,” Batteries, vol. 8, no. 2, Feb. 2022, doi: 10.3390/batteries8020010.
[23] K. Maher and R. Yazami, “A study of lithium ion batteries cycle aging by thermodynamics techniques,” J. Power Sources, vol. 247, no. May, pp. 527–533, 2014, doi: 10.1016/j.jpowsour.2013.08.053.
[24] Y. Ji, J. Liu, Y. Jiang, and Y. Liu, “Analysis of Raman and infrared spectra of poly(vinylidene fluoride) irradiated by KrF excimer laser,” Spectrochim. Acta - Part A Mol. Biomol. Spectrosc., vol. 70, no. 2, pp. 297–300, Jul. 2008, doi: 10.1016/j.saa.2007.07.061.
[25] M. M. Loghavi, S. Bahadorikhalili, N. Lari, M. H. Moghim, M. Babaiee, and R. Eqra, “The Effect of Crystalline Microstructure of PVDF Binder on Mechanical and Electrochemical Performance of Lithium-Ion Batteries Cathode,” Zeitschrift fur Phys. Chemie, vol. 234, no. 3, pp. 381–397, Mar. 2020, doi: 10.1515/zpch-2018-1343.
[26] J. Yu, Y. He, H. Li, W. Xie, and T. Zhang, “Effect of the secondary product of semi-solid phase Fenton on the flotability of electrode material from spent lithium-ion battery,” Powder Technol., vol. 315, pp. 139–146, 2017, doi: 10.1016/j.powtec.2017.03.050.
[27] H. Shin, R. Zhan, K. S. Dhindsa, L. Pan, and T. Han, “Electrochemical Performance of Recycled Cathode Active Materials Using Froth Flotation-based Separation Process,” J. Electrochem. Soc., vol. 167, no. 2, p. 020504, 2020, doi: 10.1149/1945-7111/ab6280.
[28] D. Gui, S. Chen, S. Wang, X. Tao, L. Chen, and R. Wang, “Effect of pH on surface hydration of coal particles and its attachment with oily bubbles in flotation,” Energy Sources, Part A Recover. Util. Environ. Eff., 2020, doi: 10.1080/15567036.2020.1808738.
Downloads
Published
Conference Proceedings Volume
Section
License
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.