Production of Benzene

Benzene is an important organic chemical compound that is widely used in various industries, including the production of plastics, rubber, dyes, detergents, and pharmaceuticals. There are several methods used for the production of benzene, but the correct answer in this case is option 'C' - isolation from coal tar.

Isolation from Coal Tar

Coal tar is a thick, black, viscous liquid that is obtained as a byproduct during the production of coke or coal gas from coal. It is a complex mixture of organic compounds, including benzene, toluene, xylene, and various other aromatic hydrocarbons. The isolation of benzene from coal tar involves several steps:

1. Distillation: The first step in isolating benzene from coal tar is the distillation of coal tar. Distillation is a process that separates the components of a mixture based on their boiling points. Coal tar is heated in a distillation column, and the different components evaporate at different temperatures.

2. Fractional Distillation: The distillate obtained from the distillation of coal tar is further subjected to fractional distillation. This process involves the separation of the different components of the distillate based on their boiling points. The fraction containing benzene is collected separately.

3. Purification: The benzene fraction obtained from fractional distillation is then subjected to further purification processes, such as solvent extraction or distillation under reduced pressure. These processes help remove impurities and increase the purity of benzene.

4. Final Processing: The purified benzene is then subjected to final processing steps, such as drying or filtration, to remove any remaining impurities or moisture. The resulting benzene is a highly pure form of the compound and can be used for various industrial applications.

Advantages of Isolation from Coal Tar

- Availability: Coal tar is readily available as a byproduct of the coal industry, making it a convenient source for benzene production.
- Cost-effectiveness: Isolating benzene from coal tar is a cost-effective method compared to other production methods.
- Multiple products: The isolation of benzene from coal tar also yields other useful aromatic hydrocarbons, such as toluene and xylene, which can be utilized in various industries.

Conclusion

Isolation from coal tar is one of the primary methods used for the production of benzene. This process involves distillation, fractional distillation, purification, and final processing steps to obtain a highly pure form of benzene. The availability and cost-effectiveness of coal tar make this method a preferred choice for benzene production.