K Value Calculator:
Enter the values of mole fraction of the component in the vapour phase, y and mole fraction of the same component in the liquid phase, x to determine the value of Vapour-Liquid Equilibrium Ratio, K.
K Value Formula:
The K value, also known as the vapour-liquid equilibrium (VLE) ratio, represents the ratio of the mole fraction of a component in the vapour phase to its mole fraction in the liquid phase. It is a crucial parameter in chemical engineering, particularly in distillation, absorption, and phase equilibrium calculations.
The K value varies with temperature, pressure, and composition, making it essential for designing separation processes in industries such as petroleum refining, chemical manufacturing, and gas processing.
A high K value indicates that a component prefers the vapour phase, whereas a low K value suggests that it is more likely to remain in the liquid phase.
The K value plays a vital role in designing distillation columns, where the separation efficiency depends on the difference in K values between components.
At equilibrium, each component in a multi-component system has its own K value, which must be considered in mass balance and equilibrium stage calculations.
When temperature increases, volatile components tend to have higher K values, meaning they vaporize more readily, while non-volatile components remain in the liquid phase. K values helps engineers optimize separation processes, reducing energy consumption and improving efficiency.
Vapour-Liquid Equilibrium Ratio, K is equal to the mole fraction of the component in the vapour phase, y divided by the mole fraction of the same component in the liquid phase, x.
Vapour-Liquid Equilibrium Ratio, K = y / x
K = vapour-liquid equilibrium ratio.
x = mole fraction of the component in the liquid phase.
y = mole fraction of the component in the vapour phase.
K Value Calculation:
- Calculate the K value for a component in a mixture if its mole fraction in the vapour phase is 0.6 and its mole fraction in the liquid phase is 0.2.
Given: x = 0.2, y = 0.6.
Vapour-Liquid Equilibrium Ratio, K = y / x
K = 0.6 / 0.2
K = 3.
- A component has a K value of 2.5, and its mole fraction in the liquid phase is 0.4. Calculate the mole fraction of the component in the vapour phase.
Given: x = 0.4, K = 2.5.
Vapour-Liquid Equilibrium Ratio, K = y / x
y = K * x
y = 2.5 * 0.4
y = 1.0.