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[idontknow]

I have acetone, water,cumene and phenol in my mixture and I want to set a series of columns to separate this mixture to achieve acetone and phenol as my main products.

 

 

Relative Volatilies
Acetone (highest) 

Water 
Cumene 
Phenol (lowest)

 

 

 

Since phenol and water forms an azeotrope and therefore the separation of these 2 components will be placed last.

But acetone and water is miscible which means it tends to evaporate (separated) off together.

(water is used to extract acetone from other organic component) 

 

1. if theres a Water - Phenol azeotrope 

first column will be separation of acetone 

second column will be cumene 

and last will be water and phenol (extractive)

 

2. if theres no azeotrope 

first column will be separation of acetone & water 

second column will be cumene & phenol (extractive)

 

 

My question is does acetone have effect on my azeotrope,  and how exactly do I arrange the sequence of distillation columns? 

 

 

 

[MrShorty]

It is difficult to provide a solid answer with the limited information you provide. You may have to run the simulations/calculations to really know. Off the cuff, I would expect that acetone, in sufficient concentrations, could easily have a significant impact on the activity coefficients of both water and phenol. You would have to run the calculations through your thermo/VLE model to quantify this behavior. My estimates with UNIFAC suggest that, near the azeotrope composition for water/phenol, acetone will have a more dramatic effect on the activity coefficient/volatility of phenol than for water.

 

So, short but useless answer, maybe. I certainly would not recommend pretending that the water/phenol azeotrope is not affected by the acetone present. From there, I will let you run the system through your favorite simulator/VLE model to see how it all behaves in your specific system/application.