×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

separation of mixture isopropanol-water

separation of mixture isopropanol-water

separation of mixture isopropanol-water

(OP)
Hi all,

could anybody help me with a problem? i need to separate a mixture containing 40 mol% isopropanol  and 60 mol% water, a purity at least of 99 mol% is desired for both . They say, it is useful to use solvent such as phenol or benzene, however, i cannot separate them.. And does anybody know something about Salt-effect distillation to separate my mixture?

Thanks a lot for all the answers.  

RE: separation of mixture isopropanol-water

You can use alternative way by  liquid membrane( pre separation to 8o% purity) to reduce huge load of distillation.

RE: separation of mixture isopropanol-water

Distillation is one option. I'm guessing your solution will azeotrope around 96% or so. You'll have to look at pressure distillation to get pass the azeotrope.

I do not know if a desicant material would work for seperating the water. I doubt it would be economical on the large scale.

What physically happens when an alcohol/water solution freezes? Does the alcohol seperate? I doubt that is really good solution either.

Several million dollars worth of centrifuges might do it?

As for the effects of salt distillation, do you mean adding salt to the solution? If so, the temperature in your sump will be slightly higher than that of pure water. Say 103-105*C or so. Your vapor temperature shouldn't increase past 100*C so long as you are not under pressure.

Sorry I can't do more than offer a few brain storm ideas that probably wouldn't work anyway.

 

RE: separation of mixture isopropanol-water

(OP)
Yes, Im going to use a distillation. A solution of isopropanol-water is azeotrope, from Aspen Properties I know, the min boiling point is 80.2°C and a mol fraction of isopropanol for this point is 0.675. What I can do (I guess) is to separate pure water from the azeotrope which will consists of 0.675 mol% of isopropanol and 0.325mol% of water. Then, I want to use an azeotropic distillation.. And this the problem.

Which solvent is useful? And what pressure?

It is written to use benzene for separation in Separation Process Principles by Seader. So, I try this and will see what will happen. :)

thanks..

RE: separation of mixture isopropanol-water

If this process is big enought to use distillation then I would really consider using two columns and run them at different pressures to get past the azeotrope.  That would be better than adding a third component.

Regards

StoneCold

RE: separation of mixture isopropanol-water

You can use cyclohexane

RE: separation of mixture isopropanol-water

(OP)
Thanks all,

but I need to separate these components with distillation.. Cyclohexane or benzene can help to form two liquid phases and they say, this is the way how to separate them from each other. But I still have a problem to design a column with decanter in HYSYS for my separation.. Does anybody know any tutorial to design an azeotropic distillation with decanter? Or something else? Thanks!

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources