Copper oxide ores are generally refined using a hydrometallurgical process, which involves using water-based solutions to extract and purify copper at room temperature. This typically involves three main steps: heap leaching, solvent extraction, and electrowinning.
The Hydrometallurgical Process for Refining Copper Oxide
The hydrometallurgical process is a common method for refining copper oxide. Here's a breakdown of the three key steps:
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Heap Leaching:
- The copper oxide ore is piled into large heaps.
- A leaching solution, typically a dilute acid, is trickled through the heap.
- The acidic solution dissolves the copper oxide, forming a copper-containing solution.
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Solvent Extraction (SX):
- The copper-containing solution from heap leaching is mixed with an organic solvent.
- This solvent selectively extracts the copper ions.
- The organic solvent is then separated from the original aqueous solution.
- The copper is stripped from the organic solvent using another aqueous solution.
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Electrowinning (EW):
- The concentrated copper solution from solvent extraction is then processed using electrowinning.
- In electrowinning, an electric current is passed through the solution.
- Copper ions are deposited as pure metallic copper on a cathode.
- Impurities remain in the solution.
| Step | Description |
|---|---|
| Heap Leaching | Dissolving copper oxide from ore heaps using an acidic solution. |
| Solvent Extraction | Selectively extracting and concentrating copper ions from the leach solution using organic solvents. |
| Electrowinning | Using electrolysis to deposit pure copper onto a cathode from the concentrated copper solution. |
This hydrometallurgical process provides an effective way to refine copper oxide ores into pure copper.
