[Phantom]

Hello..I am looking for UNIFAC-VLE Subgroup Parameters Table online but cant find any..where can I get it?

By the way..how should I categorize C=C compound for example butene and compound like dimethylformamide when using UNIFAC VLE method?

Thanks for helping...

[eugenedakin]

Hello Phantom,

You may wish to try 'The UNIFAC Consortium' at the following link:

http://unifac.ddbst.de/

Best wishes,

Eugene

[Phantom]

Thanks Eugenedakin...

May I Ask Another Ques?

Because I want to know the distribution of component of a non-ideal multicomponent mixture in a distillation column, I had calculated the activity coefficient for a particular multicomponent system at a temperature, lets say 60 C.
Thus I can obtain its relative volatility afterwards.

The question is would the relative volatility of this substance change or stays approximately the same when the T is being increased or decreased by let's say 30 C , considering that this system is a non ideal VLE system? I am doing this part because I wish to know its overhead temperature and distillate's temperature...

If the answer is "No"..I have to recalculate the activity coefficient but this is rather tedious as I am using UNIFAC method to calculate activity coefficient..so can I just assume that the changes in relative volatility is slight upon changes in temperature?

[Gerard]

go read "Engineering, Chemical and Biochemical Thermodynamics" by Sandler