Relationship Between Post-Leaching Particle Shape Characteristics and Rare Earth Element Recovery from Pb-Zn Flotation Tailings

Tuğba Deniz Tombal; Burçin Kaymakoğlu

doi:10.54287/gujsa.1981398

Relationship Between Post-Leaching Particle Shape Characteristics and Rare Earth Element Recovery from Pb-Zn Flotation Tailings

Abstract

This study investigates the relationship between post-leaching particle shape characteristics and the recovery of cerium (Ce), lanthanum (La), and neodymium (Nd) from Pb-Zn flotation tailings leached in H₂SO₄, HCl, and HNO₃ media. Rather than evaluating particle morphology as a factor controlling leaching performance, the study examines the morphological characteristics of solid residues obtained after leaching under the optimum conditions determined for each acid system. Leaching experiments were evaluated under previously determined optimum conditions, and the main focus of the study was placed on the morphological response of the tailings particles rather than on leaching optimization itself. Microscopic images of the raw tailings and post-leaching residues were analyzed by ImageJ to quantify circularity, roundness, solidity, aspect ratio, and porosity. The results showed that leaching performance and post-leaching particle morphology were both strongly dependent on the acid medium. Among the tested systems, H₂SO₄ and HNO₃ generally yielded higher recoveries than HCl. The highest Ce and Nd recoveries were obtained in H₂SO₄ medium (69.18% and 77.10%, respectively), whereas the highest La recovery was achieved in HNO₃ medium (79.42%). Image-based analysis revealed that H₂SO₄ leaching caused the most pronounced morphological transformation, reflected by lower roundness together with increased porosity and altered particle geometry, indicating the formation of more irregular and porous residues. In contrast, HNO₃ leaching produced a comparatively smoother and more compact residual morphology, despite yielding high recovery values, particularly for La. HCl showed an intermediate morphological response but lower overall recovery performance. The combined evaluation of leaching results and particle shape parameters demonstrated that particle morphology provides useful complementary information for interpreting acid leaching behavior. In particular, porosity alone was not sufficient to explain the recovery trends, whereas the combined interpretation of porosity, solidity, and aspect ratio offered a more meaningful description of the structural response of the tailings to acid attack. The findings indicate that the relationship between particle shape and REE recovery differs among the investigated optimum leaching systems and that image-based particle shape analysis can support the interpretation of hydrometallurgical performance in complex flotation tailings.

Keywords

Supporting Institution

This study was supported by the Scientific Research Projects Commission of Adana Alparslan Türkeş Science and Technology University.

Project Number

25103002

Ethical Statement

This study did not involve human participants, human data, animal experiments, or clinical procedures. All experimental work was conducted on flotation tailings and laboratory-generated leaching residues. Therefore, ethical approval and informed consent were not required for this study.

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Details

Primary Language

English

Subjects

Chemical-Biological Recovery Techniques and Ore Dressing , Metalic Mines

Journal Section

Research Article

Authors

Tuğba Deniz Tombal ^*
0000-0001-5658-6854
Türkiye

Burçin Kaymakoğlu
0000-0002-4885-6399
Türkiye

Early Pub Date

September 29, 2026

Publication Date

September 30, 2026

Submission Date

June 29, 2026

Acceptance Date

September 2, 2026

Published in Issue

Year 2026 Volume: 13 Number: 3

DOI

https://doi.org/10.54287/gujsa.1981398

IZ

https://izlik.org/JA87ME23PB

Cite

RIS / Bibtex

APA

Tombal, T. D., & Kaymakoğlu, B. (2026). Relationship Between Post-Leaching Particle Shape Characteristics and Rare Earth Element Recovery from Pb-Zn Flotation Tailings. Gazi University Journal of Science Part A: Engineering and Innovation, 13(3), 1311-1326. https://doi.org/10.54287/gujsa.1981398

AMA

1.Tombal TD, Kaymakoğlu B. Relationship Between Post-Leaching Particle Shape Characteristics and Rare Earth Element Recovery from Pb-Zn Flotation Tailings. GU J Sci, Part A. 2026;13(3):1311-1326. doi:10.54287/gujsa.1981398

Chicago

Tombal, Tuğba Deniz, and Burçin Kaymakoğlu. 2026. “Relationship Between Post-Leaching Particle Shape Characteristics and Rare Earth Element Recovery from Pb-Zn Flotation Tailings”. Gazi University Journal of Science Part A: Engineering and Innovation 13 (3): 1311-26. https://doi.org/10.54287/gujsa.1981398.

EndNote

Tombal TD, Kaymakoğlu B (September 1, 2026) Relationship Between Post-Leaching Particle Shape Characteristics and Rare Earth Element Recovery from Pb-Zn Flotation Tailings. Gazi University Journal of Science Part A: Engineering and Innovation 13 3 1311–1326.

IEEE

[1]T. D. Tombal and B. Kaymakoğlu, “Relationship Between Post-Leaching Particle Shape Characteristics and Rare Earth Element Recovery from Pb-Zn Flotation Tailings”, GU J Sci, Part A, vol. 13, no. 3, pp. 1311–1326, Sept. 2026, doi: 10.54287/gujsa.1981398.

ISNAD

Tombal, Tuğba Deniz - Kaymakoğlu, Burçin. “Relationship Between Post-Leaching Particle Shape Characteristics and Rare Earth Element Recovery from Pb-Zn Flotation Tailings”. Gazi University Journal of Science Part A: Engineering and Innovation 13/3 (September 1, 2026): 1311-1326. https://doi.org/10.54287/gujsa.1981398.

JAMA

1.Tombal TD, Kaymakoğlu B. Relationship Between Post-Leaching Particle Shape Characteristics and Rare Earth Element Recovery from Pb-Zn Flotation Tailings. GU J Sci, Part A. 2026;13:1311–1326.

MLA

Tombal, Tuğba Deniz, and Burçin Kaymakoğlu. “Relationship Between Post-Leaching Particle Shape Characteristics and Rare Earth Element Recovery from Pb-Zn Flotation Tailings”. Gazi University Journal of Science Part A: Engineering and Innovation, vol. 13, no. 3, Sept. 2026, pp. 1311-26, doi:10.54287/gujsa.1981398.

Vancouver

1.Tuğba Deniz Tombal, Burçin Kaymakoğlu. Relationship Between Post-Leaching Particle Shape Characteristics and Rare Earth Element Recovery from Pb-Zn Flotation Tailings. GU J Sci, Part A. 2026 Sep. 1;13(3):1311-26. doi:10.54287/gujsa.1981398