Steam Distillation and its Purpose

Steam distillation is a technique used in chemical engineering to separate volatile compounds from non-volatile compounds. It involves the use of steam to vaporize the volatile component, which is then condensed and collected separately. This method is particularly useful when the compound to be distilled is heat-sensitive and may decompose at high temperatures.

Explanation of the Correct Answer

The correct answer to the question is option 'B': Steam distillation is used to avoid thermal decomposition of a component. This means that one of the main purposes of steam distillation is to prevent the degradation or breakdown of a compound during the distillation process.

Reasoning behind the Correct Answer

1. Thermal Decomposition: Many compounds can undergo thermal decomposition at high temperatures. This can result in the formation of undesired products, loss of the compound being distilled, or even pose safety hazards. Steam distillation allows for the distillation of heat-sensitive compounds at lower temperatures, reducing the chances of thermal decomposition.

2. Lower Boiling Points: By using steam as a co-distillant, the boiling point of the mixture is lowered compared to traditional distillation methods. This allows for the separation of heat-sensitive compounds that would otherwise decompose at higher temperatures.

3. Mild Conditions: Steam distillation provides a milder and gentler distillation process compared to other methods. This is because the steam acts as a buffer and prevents direct contact between the heat source and the compound being distilled. As a result, the compound is exposed to lower temperatures, minimizing the risk of thermal decomposition.

4. Improved Yield and Purity: By avoiding thermal decomposition, steam distillation allows for the recovery of a higher yield of the desired compound. It also helps maintain the purity of the compound by preventing the formation of byproducts or degradation products.

Conclusion

In summary, steam distillation is a technique used in chemical engineering to separate volatile compounds from non-volatile compounds. One of its main purposes is to avoid the thermal decomposition of heat-sensitive compounds during the distillation process. By using steam as a co-distillant, the boiling point of the mixture is lowered, allowing for the separation of compounds at lower temperatures and reducing the chances of degradation or breakdown.