In the Froth Floatation process, zinc sulphide and lead sulphide can be separated by__________

Options

A. using collectors
B. adjusting the proportion of oil to water
C. using depressant
D. using froth stabilisers

Explanation

**Step-by-Step Solution:**

1. **Understanding Froth Flotation Process:**
- The Froth Flotation process is a method used for the separation of hydrophobic materials from hydrophilic ones, primarily in the extraction of metals from their ores.

2. **Identifying the Ores:**
- In this case, we are dealing with two sulfide ores: zinc sulfide (ZnS) and lead sulfide (PbS).

3. **Role of Depressant:**
- To separate zinc sulfide from lead sulfide, a depressant is used. A common depressant in this process is sodium cyanide (NaCN) or aniline, which selectively prevents one of the minerals from floating.

4. **Adjusting Oil to Water Proportion:**
- The separation efficiency can also be enhanced by adjusting the proportion of oil to water in the flotation process. This adjustment helps in optimizing the separation of the two sulfides.

5. **Final Separation:**
- By using the depressant and adjusting the oil-to-water ratio, zinc sulfide and lead sulfide can be effectively separated during the Froth Flotation process.

**Final Answer:**
In the Froth Flotation process, zinc sulfide and lead sulfide can be separated by using a depressant and adjusting the oil to water proportion.

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