Pyrite-assisted mechanochemical leaching of chalcopyrite concentrate in sulfuric acid under non-oxidative conditions

Scientific Reports

卷:16

Article

Mohammad Tahami¹  Vahideh Shojaei²  Mahin Schaffie³  Mohammad Ranjbar^1,3 

[1] Mineral Industries Research Center, Shahid Bahonar University of Kerman, Kerman, Iran

[2] Department of Mining Engineering, Shahid Bahonar University of Kerman, Kerman, Iran

[3] Department of Mining Engineering, Higher Education Complex of Zarand, Shahid Bahonar University of Kerman, Zarand, Iran

关键词: Chalcopyrite concentrate;    Pyrite-assisted leaching;    Mechanochemistry;    Galvanic effect;   

DOI  :  10.1038/s41598-026-58699-1

 received in 2026-05-07, accepted in 2026-06-16,  发布年份 2026

来源: Springer

【 摘 要 】

Copper extraction from chalcopyrite remains challenging due to its refractory nature and the formation of passivation layers during hydrometallurgical processing. This study investigates the mechanisms of passivation and explores mechanochemical leaching (MCL) as a strategy to enhance copper dissolution. Experiments conducted on flotation concentrate demonstrated that MCL significantly accelerates leaching, achieving a copper recovery of 27.3% under optimized conditions (3 mm beads, 310 rpm, and a 1:1 grinding media-to-liquid ratio) within 3 h, which is 70% higher than non-mechanochemical leaching. Kinetic analysis revealed two stages: an initial chemically controlled phase followed by a diffusion-limited regime, with MCL reducing activation energies by 16–21% and enhancing leaching rates by 2–6-fold. SEM–EDS confirmed the removal of passivation layers and exposure of fresh chalcopyrite surfaces. Furthermore, using pyrite as a reactive grinding medium improved copper recovery through combined mechanical abrasion and galvanic effects, achieving approximately 40% recovery in 6 h, over twice that of non-mechanochemical leaching. Overgrinding (d₈₀ ≤ 11 μm) limited long-term leaching, highlighting the importance of controlling particle size. These findings highlight the potential of MCL, particularly with reactive grinding media, to enhance chalcopyrite leaching. However, the observed recoveries indicate that industrial application will require further studies, including overgrinding control and selective addition of oxidants. Future work will focus on periodic MCL and integration of oxidants to improve copper recovery under scalable conditions.

【 授权许可】

CC BY-NC-ND   
© The Author(s) 2026

【 图 表 】

Figure 7. Representative image of 30% confluent satellite cells

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