Which of the following steps are involved in hydrometallurgical process ?

Options

A. `Cu_(2)S + 2Cu_(2)O rarr 6Cu + SO_(2)`
B. `CuFeS_(2) + 2H_(2) SO_(4) rarr CuSO_(4) + FeSO_(4) + 2H_(2) S`
C. `Ag_(2)S + 2NaCN rarr [Ag(CN)_(2)]^(Ө) + Na_(2) S`
D. `CuCO_(3) + H_(2)SO_(4) rarr CuSO_(4) + H_(2)O + CO_(2)`.

Answer

**Step-by-Step Text Solution:**

1. **Understanding Hydrometallurgy:**
- Hydrometallurgy is a method used for the extraction of metals from their ores through aqueous solutions. This process typically involves the conversion of metal ores into soluble metal compounds.

2. **Key Steps in Hydrometallurgical Process:**
- The hydrometallurgical process generally includes the following steps:
- **Leaching:** This is the first step where the ore is treated with a suitable solvent (often an acid or cyanide solution) to dissolve the metal content.
- **Separation:** After leaching, the solution containing the dissolved metal is separated from the undissolved impurities.
- **Recovery:** The dissolved metal is then recovered from the solution, often through reduction or precipitation.

3. **Examples of Reactions in Hydrometallurgy:**
- **Copper Extraction from Chalcopyrite (CuFeS2):**
- Reaction: CuFeS2 + 2 H2SO4 → CuSO4 + FeSO4 + 2 H2S
- In this reaction, chalcopyrite reacts with sulfuric acid to form copper sulfate and iron sulfate, along with hydrogen sulfide gas.

- **Silver Extraction from Silver Sulfide (Ag2S):**
- Reaction: Ag2S + 2 NaCN → 2 AgCN + Na2S
- Here, silver sulfide reacts with sodium cyanide to produce silver cyanide and sodium sulfide, which is another example of hydrometallurgical processing.

- **Copper Extraction from Copper Carbonate (CuCO3):**
- Reaction: CuCO3 + H2SO4 → CuSO4 + H2O + CO2
- In this case, copper carbonate reacts with sulfuric acid to yield copper sulfate, water, and carbon dioxide.

4. **Conclusion:**
- The steps involved in the hydrometallurgical process include leaching, separation, and recovery of metals from their ores. The examples provided illustrate specific reactions that are part of this process.