Hello everyone,
Suppose that we have a mixture of liquids at a specific temperature. How can we determine it has reached a saturation stage yet? Then, how to calculate the saturation concentration of each vapor (in ppm) if their volumes in this mixture are known.
Thank you so much for your kind attentions!
Trung
Hallo Manh,
When you can observe two phases in your mixture, then the saturation point had been reached (that is the experimental procedure). You could check the refractive index during the test.
To determinate the concentration, remember that:
ppm(i)=mass of component i / mass of mixture *100*10000
I hope that it helps you
Thank you Pablo for your answer.
I am really sorry but I have not got your point yet. Please explain "How" you can OBSERVE by an experimental procedure? Could you give me an example?
For instance, suppose we have a mixture of 1 ml H2O, 1 ml Ethanol and 2 ml Methanol at 50 °C, how can you evaluate that this mixture has reached a saturation state yet? Then, how can we determine the saturation concentration of each component in this mixture at this state? What happen if we increase/decrease temperature?
Best,
When the liquids are no longer miscible, you will see two clear phases. They do not mix thoroughly together.
The example you have given is not a good one as both of these short chain alcohols are thoroughly miscible with water, so it would be difficult to see two separate phases..
Dear Manh,
you had not mention your system in advance. But now, we all know that you have Water-Ethanol-Methanol mixture.
It is nice to try to understand your system by empirical procedures. However, this mixture is extensively studied. Therefore, I recomend you that use one of the populars modeling softwares (for example: Aspen) and try to create triangular diagrams of equilibrium.
Again, one way to "observe" the behavior experimentally is by tracking the index of refraction.
Probably, Mr. @Lakshmanan is agree whit me
Regards,
Dear Mr. Shyam Lakshmanan and Mr. Pablo,
Thank you so much for your kind attention and answers. I appreciated them.
More precisely, I would like to know "how to determine their vapor concentrations at the saturation state instead of their solution concentration". In the previous response, I just gave an example, so maybe it is not a good one.
In your opinion, are there any model or thermodynamics law we can apply in this case?
I am looking forward to hear you back.
Thanks in advance!
Dear Manh,
if I undestand correctly, you want to define the Vapour-Liquid Equilibrium (VLE) of Ethanol-Methanol-Water system, do not you?
Then my previous apreciation is still usefull.
Instead of the exprimental field i am in the simulated one. Because of that, i recommend you to use simulation sofwares.
You could try to simulate your system by NRTL Peng-Robingson EOS, for which all the parameters, in your system, must certainly are defined.
Later,
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