Phenol on reaction with dilute nitric acid , gives two products .Which method will be most efficient for large scale separation ?

Options

A. Chromatographic separation
B. Fractional Crystallisation
C. Steam distillation
D. Sublimation

Explanation

To solve the question regarding the most efficient method for large-scale separation of products obtained from the reaction of phenol with dilute nitric acid, we can follow these steps:

### Step 1: Identify the Reaction Products
When phenol reacts with dilute nitric acid, it undergoes nitration to yield two primary products: ortho-nitrophenol and para-nitrophenol.

### Step 2: Understand the Properties of the Products
- **Ortho-nitrophenol**: This compound exhibits intramolecular hydrogen bonding, which makes it more volatile compared to para-nitrophenol.
- **Para-nitrophenol**: This compound does not exhibit the same degree of intramolecular hydrogen bonding and is less volatile.

### Step 3: Analyze Separation Methods
Now, we need to analyze the provided separation methods:
1. **Chromatographic Separation**: This method is effective for small-scale separations but may not be the most efficient for large-scale operations.
2. **Recrystallization**: This method is used for purifying solid compounds but may not be suitable for separating two compounds that have similar solubility properties.
3. **Steam Distillation**: This method is particularly effective for separating volatile compounds from non-volatile impurities. Since ortho-nitrophenol is more volatile, it can be efficiently separated from para-nitrophenol using this method.
4. **Sublimation**: This method is generally used for solid compounds that can transition directly to the gas phase without becoming liquid, which may not apply here.

### Step 4: Conclusion
Given the properties of the products and the analysis of the separation methods, steam distillation is the most efficient method for large-scale separation of ortho-nitrophenol and para-nitrophenol.

### Final Answer
**The most efficient method for large-scale separation of the products is steam distillation.**

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