High relative volatility, high resistance to mass transfer in the liquid phase?
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When analyzing the plate efficiency of a distillation column, high liquid viscosity leads to difficulties in mass transfer, resulting in low plate efficiency； The relative volatility is high, the mass transfer resistance in the liquid phase is large, and the plate efficiency is low. The effect of viscosity is easy to understand, but why is the mass transfer resistance in the liquid phase high when the relative volatility is high?
I would like to ask the expert: why, when the relative volatility of two liquids is high, is the resistance to mass transfer across the liquid phase also high? Is there any connection here?
The O’Connell correlation results mentioned by the poster show the relationship between the overall plate efficiency, relative volatility, and viscosity: the effect of the relative volatility of the system components on plate efficiency. A high relative volatility means a low gas-phase solubility, or a large equilibrium constant, resulting in high mass transfer resistance in the liquid phase and low tray efficiency. Excerpt from \"Principles of Chemical Engineering, Dalian University of Technology\", page 53
A high relative volatility means a low gas-phase solubility, or a large equilibrium constant, resulting in high mass transfer resistance in the liquid phase and low tray efficiency.
Isn’t it true that a higher relative volatility makes separation easier? Then the relative volatility is high, the resistance in the liquid phase is large, and the efficiency of the tray is low (meaning more trays are required, making separation more difficult?) ), isn’t that contradictory?
Gas-liquid separation features a high relative volatility and a large equilibrium constant; if the environment is relatively enclosed, it is easy for the environment to become saturated. In liquid-liquid separation, by removing other factors, the relative volatility increases; a larger separation surface may lead to better separation results.
Could you explain more specifically why a higher relative volatility leads to greater resistance to mass transfer in the liquid phase? What is the impact of relative volatility on the resistance to mass transfer in the liquid phase?