A Study of Azeotrope and Acetone/Chloroform Liquid-Vapor Phase Diagram
A Study of Azeotrope and Acetone/Chloroform Liquid-Vapor Phase Diagram
Abstract:
Liquid-vapor phase of acetone/chloroform was studied through distilling a series of mixtures with different mole fraction. When the mixtures were boiling, their vapor was condensed through a water column and collected in a receiving container. Refractive index was collected for starting mixture, distillate and residue for each sample. A boiling temperature versus acetone’s mole fraction was constructed to show the liquid-vapor phase diagram. The boiling temperature of azeotrope was determined to be 62.2oC with the composition of 23% acetone and 77% chloroform.
Keyword: liquid-vapor phase, acetone/chloroform mixture, azeotrope
INTRODUCTION
In an ideal binary mixture, the interactions between two components A and B are equal to each other. The interaction between A-A, A-B, and B-B are the same. Raoult’s law is hold in ideal liquid mixture giving that at a specific temperature, the vapor pressure of a component is proportional to its mole fraction in the mixture.
In reality, many binary mixture do not follow Raoult’s law. The actual vapor pressure can be higher or less than what predicted by Raoult’s law and causes positive or negative deviation. For a positive deviation system, A-B interaction are favorable and the boiling temperature curve at different mole fraction gives a maximum. For a negative deviation system, A-B interaction are unfavorable and the boiling temperature curve shows a minimum. At maximum or minimum point on the curve, the composition of the liquid and of the vapor are the same. Such a mixture is called azeotrope.
This study focuses on the mixture of acetone and chloroform. To obtain a boiling temperature vs. mole fraction diagram, a series of simple distillation will be performed. Distillation basically means boiling the mixture and the vapor is obtained in a receiving container. The liquid samples will be analyzed by refractive index. In Figure 1, the
Abstract:
Liquid-vapor phase of acetone/chloroform was studied through distilling a series of mixtures with different mole fraction. When the mixtures were boiling, their vapor was condensed through a water column and collected in a receiving container. Refractive index was collected for starting mixture, distillate and residue for each sample. A boiling temperature versus acetone’s mole fraction was constructed to show the liquid-vapor phase diagram. The boiling temperature of azeotrope was determined to be 62.2oC with the composition of 23% acetone and 77% chloroform.
Keyword: liquid-vapor phase, acetone/chloroform mixture, azeotrope
INTRODUCTION
In an ideal binary mixture, the interactions between two components A and B are equal to each other. The interaction between A-A, A-B, and B-B are the same. Raoult’s law is hold in ideal liquid mixture giving that at a specific temperature, the vapor pressure of a component is proportional to its mole fraction in the mixture.
In reality, many binary mixture do not follow Raoult’s law. The actual vapor pressure can be higher or less than what predicted by Raoult’s law and causes positive or negative deviation. For a positive deviation system, A-B interaction are favorable and the boiling temperature curve at different mole fraction gives a maximum. For a negative deviation system, A-B interaction are unfavorable and the boiling temperature curve shows a minimum. At maximum or minimum point on the curve, the composition of the liquid and of the vapor are the same. Such a mixture is called azeotrope.
This study focuses on the mixture of acetone and chloroform. To obtain a boiling temperature vs. mole fraction diagram, a series of simple distillation will be performed. Distillation basically means boiling the mixture and the vapor is obtained in a receiving container. The liquid samples will be analyzed by refractive index. In Figure 1, the