×
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

Entrainer for THF/Water distillation

Entrainer for THF/Water distillation

Entrainer for THF/Water distillation

(OP)
I am looking for an entrainer to separate THF and water. I am aware that Pentane is used in certain applications however we are looking for an alternative entrainer. Any suggestions?

RE: Entrainer for THF/Water distillation

Do you mean Tetrahydrofuran?  Is one species
minimal (say less than 10%) or are they about
the same?  Do you want to recover the water or can it be wasted?   If  mixture is mostly THF then passing it through salt (NaCl) will make a  THF layer that is about
2.5% water (The bottom layer is salt water.)
I suppose you mean that pentane would entrain
THF in the top layer of a decanter.  I have experience using toluene (more toxic than pentane however).
I would imagine that THF would prefer many organics over water.

RE: Entrainer for THF/Water distillation

Sorry for my delayed comment. It happens that I adhered to the Eng-Tip forums only of late.

One technical book says that THF and water form an azeotrope with composition sensitive to pressure. So they can be effectively separated in a two-stripping column system operating at two pressures: the atmospheric, taking water as a bottom product using stripping steam as heating medium. The condensed overhead stream from this tower, serves part as reflux, the remainder is sent to the middle section of a pressure tower heated with a reboiler. The bottom stream of this column is pure THF, the top stream is condensed. Part of it is used as reflux and part re-sent to the original blend of THF and water. The pressure tower works at about 7.5 atm.
Although not exactly satisfying your request, I hope this message helps.

RE: Entrainer for THF/Water distillation

A good alternative to the pressure swing distillation will be a  combination of a distillation and vapour permeation (pervaporation). At atm. Pressure the azeotrope will be around 94% THF / 6% Water.
 90% (10% Water) can be reached with a simple distillation. The dehydration from 90% up to 99.5% is easy by pervaporation.
a general info is available under:
www.sulzerchemtech.ch/eprise/SulzerChemtech/ Sites/products_services/pervap.html
Feel free to ask for more info or sizing details.
pierre.strauch@sulzer.com

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