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2026 Vol.35, Issue 5 Preview Page

Research Paper

Recovery of Copper from Spent Battery Pre-treatment By-products Using an Air Zig-zag Classifier: Effects of Particle Size and Air Velocity

에어 지그재그 선별기를 활용한 폐배터리 전처리 공정 부산물로부터의 구리 회수: 입자 크기와 공기 유속의 영향

Seojin Moon12
,
Wonjae Lee1
,
Joobeom Seo1
,
Haeseong Jeong2
,
Seongsoo Han13*
문 서진12
,
이 원재1
,
서 주범1
,
정 해성2
,
한 성수13*
1Resources Utilization Division, Korea Institute of Geoscience and Mineral Resources(KIGAM), 124 Gwahak-ro, Yuseong-gu, Daejeon 34132, Republic of Korea
2Department of Chemical Engineering Changwon National University, Changwon 51140, Republic of Korea
3Resource Engineering, University of Science Technology (UST), 217 Gajeong-ro, Yuseong-gu, Daejeon 34113, Republic of Korea
1한국지질자원연구원 자원활용연구본부
2국립창원대학교 이차전지화학공학과
3과학기술연합대학원대학교 자원공학
*Corresponding Author
31 October 2026. pp. 87-101
PDF XML Citation
Abstract

In the mechanical pretreatment process for spent battery recycling, black mass is primarily recovered through crushing, grinding, and sieving, while the remaining coarse by-products still contain a significant amount of valuable resources, such as copper, aluminum, and separators. However, non-thermally treated pretreatment by-products are not sufficiently liberated among their constituent components, which limits their efficient recovery using conventional physical separation processes. In this study, the applicability of a vertical air separator was evaluated for the selective recovery of copper from mechanical pretreatment by-products of spent batteries by utilizing differences in particle density, shape, and aerodynamic behavior. Prior to separation, the occurrence characteristics of the constituent components in the byproducts were investigated using SEM-EDS analysis. The results confirmed that copper current collectors existed as thin foils from which most of the anode active material had been detached, whereas aluminum current collectors remained in a poorly liberated state with cathode active materials strongly attached, resulting in an increased apparent mass. Particle behavior simulation reflecting these differences in shape and mass showed that the critical air velocity required for particle floating increased in the order of separator, copper, and aluminum–cathode composite. In addition, the aerodynamic behavior difference between copper and aluminum decreased as particle size decreased. Based on the simulation results, gravity separation experiments were conducted using a vertical air separator. The experimental results showed that the behavior difference between copper and aluminum–cathode composites was more distinct in the coarse size fraction (+1000–1400 μm) than in the fine size fraction (+355–500 μm), leading to relatively higher copper separation efficiency. These findings demonstrate the feasibility of physical separation based on the aerodynamic behavior differences of copper, aluminum, and separators in non-thermally treated mechanical pretreatment byproducts of spent batteries. This approach is expected to provide a promising route for recovering valuable resources from pretreatment byproducts that have conventionally been mixed, discarded, or treated as bulk waste.

Keywords
Spent lithium-ion batteries
Mechanical pretreatment
Pretreatment by-products
Copper recovery
Vertical air separation

폐배터리 재활용을 위한 기계적 전처리 공정에서는 파쇄, 분쇄 및 체질을 통해 블랙매스가 우선적으로 회수되며, 이후 발생하는 조립 부산물에는 구리, 알루미늄, 분리막 등 유가 자원이 다량 잔존한다. 그러나 열처리를 거치지 않은 전처리 부산물은 구성 성분 간 단체분리가 충분하지 않아, 기존 물리적 선별 공정만으로는 효율적인 회수에 한계가 있다. 본 연구에서는 폐배터리 기계적 전처리 공정 부산물로부터 구리를 선택적으로 회수하기 위해, 입자의 밀도, 형상 및 공기역학적 거동 차이를 이용하는 수직형 기류선별기의 적용 가능성을 평가하였다. 선별에 앞서 SEM-EDS 분석을 통해 부산물 내 구성 성분의 존재 형태를 분석한 결과, 구리 집전체는 음극활물질이 대부분 탈착된 박막 형태로 존재한 반면, 알루미늄 집전체는 양극활물질이 강하게 부착된 미단체분리 상태로 존재하여 겉보기 질량이 증가한 것을 확인하였다. 이러한 형상 및 질량 차이를 반영한 입자 거동 시뮬레이션 결과, 입자를 부상시키기 위한 임계 공기 유속은 분리막, 구리, 알루미늄–양극재 복합체 순으로 증가하였으며, 입자 크기가 작아질수록 구리와 알루미늄 간 공기역학적 거동 차이는 감소하는 것으로 나타났다. 시뮬레이션 결과를 바탕으로 수직형 기류선별기를 이용한 비중선별 실험을 수행한 결과, 미립 구간 (+355–500 μm)보다 조립 구간 (+1000–1400 μm)에서 구리와 알루미늄–양극재 복합체 간 거동 차이가 뚜렷하게 나타났으며, 이에 따라 상대적으로 높은 구리 선별 효율을 달성하였다. 본 연구는 열처리를 거치지 않은 폐배터리 기계적 전처리 부산물에서 구리, 알루미늄 및 분리막의 공기역학적 거동 차이를 기반으로 한 물리적 분리 가능성을 제시하며, 기존에 혼합 폐기되거나 일괄 처리되던 전처리 부산물의 유가자원 회수 공정으로 활용될 수 있을 것으로 기대된다.

키워드
폐배터리
기계적 전처리
전처리 부산물
구리 회수
수직형 기류선별
References
1

Bruce, P. G., 2026 : Unforeseen triumphs in batteries and the road ahead, Nature Energy, 11(1), pp.26-27.

10.1038/s41560-025-01960-0
2

Tas, G., Vänskä, J. and Araya-Gomez, N., 2026 : An integrated study on pyrolysis, flotation, and leaching for optimized recycling of industrial battery materials, Mineral Engineering, 235, 109839.

10.1016/j.mineng.2025.109839
3

Khodadadmahmoudi, G., Javdan Tabar, K., Homayouni, A. H., et al., 2023 : Recycling spent lithium ion batteries-an overview of pretreatment flowsheet development based on metallurgical factors, Environmental Technology Reviews, 12(1), 2248559.

10.1080/21622515.2023.2248559
4

Kar, U., Fahimi, A., Suponik, T., et al., 2025 : Comparison of different pretreatment processes for lithium-ion battery recycling from a life cycle assessment perspective, Journal of Environmental Management, 392, 126798

10.1016/j.jenvman.2025.126798
5

Goodenough, J. B. and Park, K. S., 2013 : The Li-Ion Rechargeable Battery: A Perspective, Journal of the American Chemical Society, 135(4), pp.1167-1176.

10.1021/ja3091438
6

Xu, C., Peng, B., Yang, W., et al., 2025 : High energy density lithium battery systems: from key cathode materials to pouch cell design, Chemical Society Reviews, 54, pp.10245-10303.

10.1039/D5CS00641D
7

Jiang, S. Q., Nie, C. C., Shi, S. X., et al., 2023 : Enhancements of dissociation of electrode materials in spent lithium-ion batteries by low-temperature heating pre-treatment, Process Safety and Environmental Protection, 170, pp.908-920.

10.1016/j.psep.2022.12.061
8

Du, K., Ang, E. H., Wu, X., et al., 2022 : Progresses in sustainable recycling technology of spent lithium‐ion batteries, Energy & Environmental Materials, 5(4), pp.1012-1036.

10.1002/eem2.12271
9

Zhang, G., Yuan, X., He, Y., et al., 2021 : Recent advances in pretreating technology for recycling valuable metals from spent lithium-ion batteries, Journal of hazardous materials, 406, 124332.

10.1016/j.jhazmat.2020.124332
10

Yu, D., Huang, Z., Makuza, B., et al., 2021 : Pre-treatment options for the recycling of spent lithium-ion batteries: A comprehensive review, Mineral Engineering, 173, 107218.

10.1016/j.mineng.2021.107218
11

Liu, B., Zhou, J., Yang, L., et al., 2026 : Impacts of pretreatment routes on spent lithium-ion batteries recycling, Nature Sustainability, 9(4), pp.626-638.

10.1038/s41893-026-01767-1
12

Lee, W., Seo, J., Han, S., 2026 : Energy-efficient mechanical treatment process design for recycling of end-of-life lithium-ion batteries, Process Safety and Environmental Protection, 109378.

10.1016/j.psep.2026.109378
13

Das, P., Hewage, K., Kotagodahetti, R., et al., 2025 : Lithium-ion battery recycling: a critical review of techno-economical and socio-environmental impacts, Separation and Purification Technology, 135847.

10.1016/j.seppur.2025.135847
14

Zhu, P., Driscoll, E. H., Dong, B., et al., 2023 : Direct reuse of aluminium and copper current collectors from spent lithium-ion batteries, Green Chemistry, 25(9), pp.3503-3514.

10.1039/D2GC03940K
15

Bologna, A. J., Liu, D., Antall, S. A., et al., 2025 : Impact of Al and Cu Current Collectors on Li-Ion Battery Recycling, ACS Sustainable Resource Management, 3(1), pp.223-232.

10.1021/acssusresmgt.5c00528
16

Zhu, P., Driscoll, E. H., Dong, B., et al., 2023 : Direct reuse of aluminium and copper current collectors from spent lithium-ion batteries, Green Chemistry, 25(9), pp.3503-3514.

10.1039/D2GC03940K
17

Amoah, M., Brown, M., Simon, A., et al. 2026 : Mineral demand from AI data centers: Infrastructure intensity, processing bottlenecks, and supply competition, Resources Policy, 119, 105970.

10.1016/j.resourpol.2026.105970
18

Wang, L., Wang, Y., Zhang, S. A., et al., 2025 : Efficient separation of copper and aluminum foils from spent lithium-ion batteries via sulfidization flotation, Journal of Environmental Chemical Engineering, 119411.

10.1016/j.jece.2025.119411
19

Zhong, X., Liu, W., Han, J., et al., 2019 : Pyrolysis and physical separation for the recovery of spent LiFePO4 batteries. Waste Management, 89, pp.83-93.

10.1016/j.wasman.2019.03.068
20

He, Y., Yuan, X., Zhang, G., et al., 2021 : A critical review of current technologies for the liberation of electrode materials from foils in the recycling process of spent lithium-ion batteries, Science of The Total Environment, 766, 142382.

10.1016/j.scitotenv.2020.142382
21

Saneie, R., Abdollahi, H., Ghassa, S., et al., 2022 : Recovery of copper and aluminum from spent lithium-ion batteries by froth flotation: a sustainable approach, Journal of Sustainable Metallurgy, 8(1), pp.386-397.

10.1007/s40831-022-00493-0
22

Khodadadmahmoudi, G., Javdan Tabar, K., Homayouni, A. H., et al., 2023 : Recycling spent lithium batteries–an overview of pretreatment flowsheet development based on metallurgical factor, Environmental Technology Reviews, 12(1), 2248559.

10.1080/21622515.2023.2248559
23

Lombardo, G., Ebin, B., Foreman, M. R. S. J., et al., 2020 : Incineration of EV Lithium-ion batteries as a pretreatment for recycling–Determination of the potential formation of hazardous by-products and effects on metal compounds, Journal of hazardous materials, 393, 122372.

10.1016/j.jhazmat.2020.122372
24

Siame, M. C., Ahmed, H. M., Andersson, A., et al., 2026 : Understanding the thermal behavior of black mass during recycling of spent lithium-ion batteries through its individual components, ACS Sustainable Chemistry & Engineering, 14(4), pp.1952-1963.

10.1021/acssuschemeng.5c10344
25

Zhong, X., Liu, W., Han, J., et al., 2020 : Pneumatic separation for crushed spent lithium-ion batteries, Waste Management, 118, pp.331-340.

10.1016/j.wasman.2020.08.053
26

Zhu, X., Zhang, C., Feng, P., et al., 2021 : A novel pulsated pneumatic separation with variable-diameter structure and its application in the recycling spent lithium-ion batteries, Waste Management, 131, pp.20-30.

10.1016/j.wasman.2021.05.027
27

Bi, H., Zhu, H., Zu, L., et al., 2019 : A new model of trajectory in eddy current separation for recovering spent lithium iron phosphate batteries, Waste Management, 100, pp.1-9.

10.1016/j.wasman.2019.08.041
28

Silva, A. S., Sousa, M. E., Braga, E. M., et al., 2024 : Morphological and doping effects on electrical conductivity of aluminum metal substrate through pulsed electrodeposition coating of Cu-MWCNT, Metals, 14(9), 1060.

10.3390/met14091060
29

Saeed, A., Madkhli, A. Y., Al-Dossari, M., et al., 2022 : Electrical and dielectric properties of composites composed of natural quartz with aluminum, Silicon, 14(15), pp.9517-9531.

10.1007/s12633-022-01713-8
30

Wang, H., Li, Z., Yang, Z., et al., 2025 : Interface-engineered core–shell quantum dots enable carrier confinement in polymer nanodielectrics for high-voltage direct current applications, ACS Applied Materials & Interfaces, 17(28), pp.41002-41014.

10.1021/acsami.5c05811
31

Ma, Y., Wu, D., Liu, Y., et al., 2014 : Electrically conductive and super-tough polypropylene/carbon nanotube nanocomposites prepared by melt compounding, Composites Part B: Engineering, 56, pp.384-391.

10.1016/j.compositesb.2013.08.026
32

Miß, V., Seus, S., Marx, A., et al., 2025 : Influence of Pressure, Particle Morphology, Coating, and Heat Treatment on the Effective Electronic Conductivity of Cathode Active Materials for All-Solid-State Batteries, ACS Materials Letters, 7(6), pp.2262-2269.

10.1021/acsmaterialslett.4c02595
33

Liu, Z., Shi, Y., Yang, Q., et al., 2023 : Effects of crystal structure and electronic properties on lithium storage performance of artificial graphite, RSC advances, 13(43), pp.29923-29930.

10.1039/D3RA05785B
34

Davey, W. P., 1925 : Precision measurements of the lattice constants of twelve common metals, Physical Review, 25(6), pp.753-761.

10.1103/PhysRev.25.753
35

Stead, J. L., de Souza Leite, L., Bond, T., 2024 : Gradient columns to measure the density of microplastics, Science of The Total Environment, 953, 176176.

10.1016/j.scitotenv.2024.176176
36

Malik, M., Chan, K. H., Azimi, G., 2022 : Review on the synthesis of LiNixMnyCo1-x-yO2 (NMC) cathodes for lithiumion batteries, Materials Today Energy, 28, 101066.

10.1016/j.mtener.2022.101066
37

Mo, R., Tan, X., Li, F. et al., 2020 : Tin-graphene tubes as anodes for lithium-ion batteries with high volumetric and gravimetric energy densities, Nature communications, 11(1), 1374.

10.1038/s41467-020-14859-z32170134PMC7069972
38

Purcell, E. M. and Morin, D. J., 2013 : Electricity and Magnetism, p.95, 3rd Edition, Cambridge University Press, Cambridge.

10.1017/CBO9781139012973
39

Klinser, G., Stückler, M., Kren, H., et al., 2018 : Charging processes in the cathode LiNi0.6Mn0.2Co0.2O2 as revealed by operando magnetometry, Journal of Power Sources, 396, pp.791-795.

10.1016/j.jpowsour.2018.06.090
40

Mukai, K., Inoue, T., 2017 : Magnetic susceptibility measurements on Li-intercalated graphite: Paramagnetic to diamagnetic transitions in C12Li induced by magnetic field, Carbon, 123, pp.645-650.

10.1016/j.carbon.2017.08.012
41

Sun, H. H., Manthiram, A., 2017 : Impact of microcrack generation and surface degradation on a nickel-rich layered Li [Ni0.9Co0.05Mn0.05] O2 cathode for lithium-ion batteries, Chemistry of materials, 29(19), pp.8486-8493.

10.1021/acs.chemmater.7b03268
42

Luo, M., Mijailovic, A. S., Wang, G., et al., 2024 : Understanding particle size effect on fast-charging behavior of graphite anode using ultra-thin-layer electrodes, Journal of Energy Storage, 104, 114521.

10.1016/j.est.2024.114521
43

Zhang, G., Zhou, W., Chen, M., et al., 2023 : Stainless steel foil: A more appropriate current collector than titanium foil for the cathodes of aqueous zinc ion batteries, Electrochimica Acta, 437, 141519.

10.1016/j.electacta.2022.141519
44

Ryou, M. H., Lee, Y. M., Park, J. K., et al., 2011 : Mussel-inspired polydopamine-treated polyethylene separators for high-power Li-ion batteries, Advanced materials, 23(27), pp.3066-3070.

10.1002/adma.201100303
45

Parikh, D., Christensen, T., Hsieh, C. T., et al.. 2019 : Elucidation of separator effect on energy density of Li-ion batteries, Journal of The Electrochemical Society, 166(14), pp.3377-A3383.

10.1149/2.0571914jes
46

Vanderbruggen, A., Sygusch, J., Rudolph, M., et al., 2021 : A contribution to understanding the flotation behavior of lithium metal oxides and spheroidized graphite for lithium-ion battery 5 novel pulsated pneumatic separation with variable-diameter structure and its application in the recycling spent lithium-ion batteries, Waste Management, 131, pp.20-30.

10.1016/j.wasman.2021.05.027
47

Zhu, X., Zhang, C., Feng, P., et al., 2021 : A novel pulsated pneumatic separation with variable-diameter structure and its application in the recycling spent lithium-ion batteries, Waste Management, 131, pp. 20-30.

10.1016/j.wasman.2021.05.027
48

Shapiro, M., Galperin, V., 2005 : Air classification of solid particles: a review, Chemical Engineering and Processing, 44(2), pp.279-285.

10.1016/j.cep.2004.02.022
49

Silva, M. D. F. D., Dutra, A. J. B. and Mansur, M. B., 2019 : Enrichment of Copper, Lead, and Tin by Mechanical Dry Processing of Obsolete Printed Circuit Board Residues, Materials Research, 22(5), e20190341.

10.1590/1980-5373-mr-2019-0341
50

Biddulph, M. W. and Connor, M. A., 1989 :　A Method of Comparing the Performance of Air Classifiers, Resources, Conservation and Recycling, 2(4), pp.275-286.

10.1016/0921-3449(89)90004-9
51

Banjac, V., Pezo, L., Pezo, M., et al., 2017 : Optimization of the classification process in the zigzag air classifier for obtaining a high protein sunflower meal–Chemometric and CFD approach, Advanced Powder Technology, 28(3), pp.1069-1078.

10.1016/j.apt.2017.01.013
52

Tomas, J., 2004 : Gravity Separation of Particulate Solids in Turbulent Fluid Flow, Particulate Science and Technology, 22(2), pp.169-187.

10.1080/02726350490457222
53

Roloff, C., Lukas, E., van Wachem, B., et al., 2019 : Particle dynamics investigation by means of shadow imaging inside an air separator, Chemiacal Engineering Science, 195, pp.312-324.

10.1016/j.ces.2018.09.020
54

Tavares, L. M., 2000 : Role of particle microstructure in comminution, Developments in Mineral Processing, Vol. 13, C4-99-C4-106, Elesevier, Amsterdam

10.1016/S0167-4528(00)80033-2
55

Zhu, P., Gastol, D., Marshall, J., et al., 2021 : A review of current collectors for lithium-ion batteries, Journal of Power Sources, 485, 229321.

10.1016/j.jpowsour.2020.229321
56

Lederer, M., Gröger, V., Khatibi, G., et al., 2010 : Size dependency of mechanical properties of high purity aluminium foils, Materials Science and Engineering: A, 527(3), pp.590-599.

10.1016/j.msea.2009.08.016
57

Mao, K., Yao, Y., Chen, Y., et al., 2024 : Fracture mechanisms of NCM polycrystalline particles in lithium-ion batteries: A review, Journal of Energy Storage, 84, 110807.

10.1016/j.est.2024.110807
58

Stallard, J. C., Wheatcroft, L., Booth, S. G., et al., 2022 : Mechanical properties of cathode materials for lithium-ion batteries, Joule, 6(5), pp.984-1007.

10.1016/j.joule.2022.04.001
59

Ayatollahi, M. R., Berto, F. and Lazzarin, P., 2011 : Mixed mode brittle fracture of sharp and blunt V-notches in polycrystalline graphite, Carbon, 49(7), pp.2465-2474.

10.1016/j.carbon.2011.02.015
60

Chen, H., Lu, Z., Su, R. K. L., et al., 2023 : Determination of tensile strength and fracture toughness of nuclear graphite and prediction of its structural failures, Journal of Materials Research and Technology, 27, pp.3565-3578.

10.1016/j.jmrt.2023.10.114
61

Yang, W., Tong, Z., Bu, X. and Dong, L., 2025 : Research progress on the separation of cathode materials from metal current collectors of spent lithium-ion batteries, Journal of Industrial and Engineering Chemistry, 148, pp.27-37.

10.1016/j.jiec.2024.12.074
62

Ji, Y., Jafvert, C. T., Zyaykina, N. N., et al., 2022 : Decomposition of PVDF to delaminate cathode materials from end-of-life lithium-ion battery cathodes, Journal of Cleaner Production, 367, 133112.

10.1016/j.jclepro.2022.133112
63

Alolaywi, H., Uzun, K. and Cheng, Y. T., 2025 : Low porosity NMC622 and NMC811 electrodes made by severe calendering, Journal of Energy Storage, 105, 114559.

10.1016/j.est.2024.114559
Information
  • Publisher :The Korean Institute of Resources Recycling
  • Publisher(Ko) :한국자원리싸이클링학회
  • Journal Title :Resources Recycling
  • Journal Title(Ko) :자원리싸이클링
  • Volume : 35
  • No :5
  • Pages :87-101
  • Received Date : 2026-09-04
  • Revised Date : 2026-10-01
  • Accepted Date : 2026-10-06
  • DOI :https://doi.org/10.7844/kirr.2026.35.5.87
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