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Theoretical composition determination through UNIFAC

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xnxnxnxn

Chemical
Feb 21, 2013
2
Hello everyone, i'm new to this forum so i'm not sure if i'm posting where it should be, and sorry in advance for that.
I'm having some trouble with this system i got, the experimental data i have is the following:

Temperature = 25 deg.C (constant)
Pressure = 15 different values from 3,2 to 7,4 kPa
Liquid and Vapour Composition of component 1 = 15 different values from 0 to 1 related to each other (for every liquid x i have a vapour y)
Components = Toluene and Isopropanol (2-propanol)

What i want to do is use UNIFAC to find values of Gama1 and Gama2, then use this on Antoine's eq. to find if the theoretical vapour composition matches the experimental. However, since the temperature is always the same, i can't find the saturation pressure through Antoine, and therefore i can't find the vapour comp.
So is there anyway around this or should i try another method?

Thanks in advance.
 
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RHSQ

Maybe I am not understanding your quastion, but the Antoine's equation is written for pure components and not mixtures like this one you have.
But once you use the UNIFAC to find Gama1, for exemple, you will find the vapour composition by Raouls law

P*y1=Gama1*p1*x1 .: (p1 - vapuor pressure of component 1;P - pressure of the system)

So you have

y1=(Gama1*p1*x1)/P

The same for y2

Hope I could help
 
Yes, thank you. I Found later that what i was doing was wrong, and i had to calculate phi as well.
Thanks for your reply!
 
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