About this Abstract |
| Meeting |
2026 TMS Annual Meeting & Exhibition
|
| Symposium
|
Advances in Recycling and Environmental Technologies
|
| Presentation Title |
Decopperization of Copper Anode Slimes by Hot Leaching: A Case Study at Mopani Copper Mines |
| Author(s) |
Chinyanta Ndhlovu, Yotamu Hara, Rodrick Mulenga Lamya, Leonard Mulenga Kabondo, Sackson Chisempi, Charles Mazala, Richard Phiri, Tinah Chanda Phiri |
| On-Site Speaker (Planned) |
Chinyanta Ndhlovu |
| Abstract Scope |
Copper anode slimes from electrolytic refining contain significant amount of copper (>60 %) along with precious and other base metals. Decopperization, the selective dissolution of Cu while retaining valuable metals, is a critical pretreatment step. This study investigates leaching of anode slimes using sulfuric acid in the presence and absence of hydrogen peroxide. Different leaching parameters such as temperature, pulp density, leaching time, pH and oxidant (hydrogen peroxide) addition were investigated. The results showed that the addition of hydrogen peroxide significantly increases leach efficiency of copper. However, the reactions are more favorable at lower (60 °C) than at higher (90 °C) temperature. Mass balances indicated that 90% of copper reported to the solution (10% remained in residue), whereas only 20% of arsenic dissolved during leaching. Kinetic analysis using shrinking-core model equations (1 – (1–X)(1/3) = k_r·t and 1 – ⅔X – (1–X)(2/3) = k_d·t) yielded R² ≈ 0.96 for surface-reaction control and R² ≈ 0.99 for diffusion control, indicating a diffusion-controlled process. These results confirm that optimized hot oxidative leaching effectively removes copper, thus achieving decopperization. |
| Proceedings Inclusion? |
Undecided |