Which step is not involved in hydrometallurgical process ?

Options

A. ` Cu_ 2 S + 2 Cu_ 2 O to 6 Cu + SO _ 2 `
B. ` CuSO_ 4 + Fe to Cu + Fe SO _ 4 `
C. `Cu Fe S_ 2 + 2 H_ 2 SO _ 4 to Cu SO _ 4 + Fe SO _ 4 + 2 H_ 2 S `
D. ` Cu CO _ 3 + H _ 2 SO _ 4 to Cu SO _ 4 + CO _ 2 + H _ 2 O `

Answer

To determine which step is not involved in the hydrometallurgical process, we first need to understand what the hydrometallurgical process entails. Here’s a step-by-step breakdown of the process:

### Step 1: Understanding Hydrometallurgy
Hydrometallurgy is a method of extracting metals from their ores using aqueous solutions. The process generally involves the following steps:
- **Leaching**: The ore is treated with a solvent (usually water or an acid) to dissolve the desired metal.
- **Separation**: The solution containing the metal ions is separated from the undissolved ore.
- **Recovery**: The metal is recovered from the solution, typically through reduction or precipitation.

### Step 2: Identifying the Steps
1. **Leaching**: This is the first step where the ore is dissolved in a suitable solvent.
2. **Separation**: After leaching, the solution containing the dissolved metal is separated from the solid waste.
3. **Recovery**: The final step involves recovering the metal from the solution, often through chemical reduction or electrolysis.

### Step 3: Analyzing the Options
Now, we need to analyze the options provided in the question to identify which one does not fit into the hydrometallurgical process.

- **Option 1**: Not involving an aqueous solution or reduction process.
- **Option 2**: Involves leaching and recovery of metals.
- **Option 3**: Involves leaching and recovery of metals.
- **Option 4**: Involves leaching and recovery of metals.

### Step 4: Conclusion
Based on the analysis, **Option 1** is the step that is not involved in the hydrometallurgical process, as it does not include the necessary steps of leaching, separation, or recovery.

### Final Answer
The step that is not involved in the hydrometallurgical process is **Option 1**.

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