Thu Doan
Chem 2211-02
Fractional Distillation of a Binary Mixture 1. Explain why a packed fractional distillation column is more efficient than an unpacked column for separating two closely boiling liquids.
Packing in the columns create more theoretical plates, which means better efficiency for distillation. The packed fractional distillation column provides a large surface area for heat exchange between the vapor and liquid. This allows for better separation between the liquids.
11. a) A mixture of 60 mol % n-propylcyclohexane and 40 mol % n-propylbenzene is distilled through a simple distillation apparatus; assume that no fractionation occurs during the distillation. The boiling temperature is found to be 157 °C (760 torr) as the first small amount of distillate is collected. The standard vapor pressures of n-propylcyclohexane and n-propylbenzene are known are known to be 769 torr and 725 torr, respectively, at 157.3 °C. Calculate the percentage of each of the two components in the first few drops of distillate. …show more content…
b) A mixture of 50 mol % benzene and 50 mol % toluene is distilled under exactly the same conditions as in Part a. Using Figure 4.3, determine the distillation temperature and the percentage composition of the first few drops of distillate.
The distillation temperature is 93 °C. The percentage composition is 75 mole percent of benzene and 25 mole percent of
Chem 2211-02
Fractional Distillation of a Binary Mixture 1. Explain why a packed fractional distillation column is more efficient than an unpacked column for separating two closely boiling liquids.
Packing in the columns create more theoretical plates, which means better efficiency for distillation. The packed fractional distillation column provides a large surface area for heat exchange between the vapor and liquid. This allows for better separation between the liquids.
11. a) A mixture of 60 mol % n-propylcyclohexane and 40 mol % n-propylbenzene is distilled through a simple distillation apparatus; assume that no fractionation occurs during the distillation. The boiling temperature is found to be 157 °C (760 torr) as the first small amount of distillate is collected. The standard vapor pressures of n-propylcyclohexane and n-propylbenzene are known are known to be 769 torr and 725 torr, respectively, at 157.3 °C. Calculate the percentage of each of the two components in the first few drops of distillate. …show more content…
b) A mixture of 50 mol % benzene and 50 mol % toluene is distilled under exactly the same conditions as in Part a. Using Figure 4.3, determine the distillation temperature and the percentage composition of the first few drops of distillate.
The distillation temperature is 93 °C. The percentage composition is 75 mole percent of benzene and 25 mole percent of