Relates compositions of vapour and liquid phases.
VLE describes compositions of liquid and vapour in equilibrium: Raoult's law y_iP=x_iP_i^{sat} for ideal mixtures; relative volatility α=(y_A/x_A)/(y_B/x_B). Azeotropes (ethanol-water 95.6%) limit simple distillation. Data from T-x-y and x-y diagrams.
At 1 atm ethanol-water cannot be distilled beyond about 95.6% ethanol.
Vapour-liquid equilibrium relates the composition of the vapour and liquid, which is the basis of distillation design.
Relates compositions of vapour and liquid phases.
Vapour-liquid equilibrium relates the composition of the vapour and liquid, which is the basis of distillation design.
The ratio of the vapour-liquid equilibrium constants of two components, which measures how easily they separate by distillation.
For an ideal mixture the partial pressure of a component equals its mole fraction times its vapour pressure.
Typical applications include predicting the vapour composition above a mixture of ethanol and water, designing a flash drum to separate light components and choosing the operating pressure of a column for a given separation.
Study "Chemical thermodynamics" first (topic 70 of 100 in Materials & Chemical). It covers the groundwork this topic builds on.
Bubble and dew points. Antoine equation. Non-ideal activity coefficients.
At 1 atm ethanol-water cannot be distilled beyond about 95.6% ethanol.
The next topic is "Distillation", which builds directly on this one.
It is classed as Advanced in Materials & Chemical (topic 71 of 100). It is an advanced topic. It assumes you are comfortable with the intermediate topics in Materials & Chemical.
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