Which catalyst is used to convert alcohol directly to petrol?

Answer

**Step-by-Step Solution:**

1. **Understanding the Process**: The conversion of alcohol to petrol (gasoline) involves a catalytic process. Catalysts are substances that increase the rate of a chemical reaction without being consumed in the process.

2. **Identifying the Catalyst**: The specific catalyst used for converting alcohol directly to petrol is known as ZSM-5. ZSM-5 is a type of zeolite, which is a microporous aluminosilicate material.

3. **Function of ZSM-5**: The ZSM-5 catalyst works by dehydrating alcohol. During this dehydration process, the alcohol loses water (H2O) and is transformed into a mixture of hydrocarbons.

4. **Characteristics of ZSM-5**:
- **Shape Selectivity**: ZSM-5 is a shape-selective catalyst, meaning it can preferentially catalyze reactions for certain shapes of molecules, which is beneficial for producing specific hydrocarbons found in gasoline.
- **Honeycomb Structure**: It has a honeycomb-like structure that provides a large surface area for reactions.
- **Microporous Nature**: ZSM-5 has a microporous structure, which allows for the selective passage of small molecules while blocking larger ones.

5. **Final Outcome**: The end result of using ZSM-5 as a catalyst in the dehydration of alcohol is the production of gasoline, which is a mixture of hydrocarbons suitable for use as fuel.

**Final Answer**: The catalyst used to convert alcohol directly to petrol is Zeolite ZSM-5.

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