The process used for purification of bauxite ore containing iron oxide impurity is known as

Options

A. Hoope's process
B. Serpeck's process
C. Baeyer's process
D. Electrolytic process

Explanation

**Step-by-Step Solution:**

1. **Understanding Bauxite Ore**: Bauxite is the primary ore of aluminum and often contains impurities such as iron oxide. The goal is to purify bauxite to extract aluminum oxide (Al2O3).

2. **Identifying the Purification Process**: The process used for the purification of bauxite ore is known as the Baeyer's process. This process specifically targets the removal of iron oxide impurities.

3. **Chemical Reaction in Baeyer's Process**:
- In the Baeyer's process, bauxite (which contains aluminum oxide) is treated with sodium hydroxide (NaOH) and water.
- The reaction forms sodium aluminate (NaAl(OH)4) in solution.

4. **Formation of Aluminum Hydroxide**:
- The sodium aluminate solution is then reacted with carbon dioxide (CO2), which leads to the precipitation of aluminum hydroxide (Al(OH)3).
- The reaction can be summarized as:
\[ 2 \text{NaAl(OH)}_4 + \text{CO}_2 \rightarrow \text{Al}_2\text{O}_3 \cdot \text{XH}_2\text{O} + 2 \text{NaHCO}_3 \]

5. **Dehydration of Aluminum Hydroxide**:
- The aluminum hydroxide precipitate (Al(OH)3) is then heated to remove water, yielding pure aluminum oxide (Al2O3).
- The heating process can be represented as:
\[ \text{Al}_2\text{O}_3 \cdot \text{XH}_2\text{O} \xrightarrow{\text{heat}} \text{Al}_2\text{O}_3 + \text{XH}_2\text{O} \]

6. **Conclusion**: The Baeyer's process effectively purifies bauxite by removing iron oxide and yielding aluminum oxide, making it the correct answer to the question.

**Final Answer**: The process used for purification of bauxite ore containing iron oxide impurity is known as the **Baeyer's process**.

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