Components of azeotropic distillate
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The mixture of ethanol and water has an azeotropic point. So during the distillation process of the mixture containing 10% (mass) ethanol, will the gas phase composition be an azeotropic composition or an equilibrium composition?
This post was last edited by zhangyong6404 on 2009-9-7 13:24 The azeotropic point of ethanol and water is 78.1°C, and the azeotrope composition contains 4.4% water. That is to say, in the case of azeotropic distillation, the water content of the overhead distillate is 4.4%, which is an azeotropic composition. The remaining water remains in the tower kettle.
After distillation, the composition at the top of the tower must be an azeotropic composition. But if it is a simple distillation and the mixed solution is heated, will the steam composition remain an azeotropic composition until the ethanol is evaporated, or will the steam composition become an equilibrium composition?
I think the ethanol can be evaporated until water is left, and the steam component is an azeotropic component.
The azeotropic point of the system of ethanol and water is 89.4%
If the steam composition is an azeotropic composition, then does the txy diagram of ethanol and water have no meaning? I personally think that in the distillation of ethanol and water, the top product will eventually have an azeotropic composition. In simple distillation, the gas phase composition will still be an equilibrium composition.
I think it should be an azeotropic composition.
Azeotrope is also a manifestation of equilibrium, right?
Regardless of the composition, the first thing to evaporate is the azeotrope.
10% ethanol-water solution, during distillation, if there are enough trays or packings, the top of the tower will be close to azeotrope； If a continuous steady-state simple distillation is performed, the gas phase must have an equilibrium composition and will not reach an azeotrope. ； If intermittent simple distillation is performed, there will be less and less ethanol in the liquid phase and gas phase, and it is impossible to reach an azeotrope in the end.