March 28, 2024, 02:11:26 PM
Forum Rules: Read This Before Posting


Topic: no bubbles in distillation of phenylacetone under vacuum  (Read 3583 times)

0 Members and 1 Guest are viewing this topic.

Offline shak22

  • New Member
  • **
  • Posts: 8
  • Mole Snacks: +0/-0
no bubbles in distillation of phenylacetone under vacuum
« on: December 03, 2012, 03:06:54 AM »
hello,
i have no bubbles in distillation of phenylacetone under vacuum, the heat is about 100c, and the vacuum pump produce around 20 torr.

is that normal? please help me.

Offline discodermolide

  • Chemist
  • Sr. Member
  • *
  • Posts: 5038
  • Mole Snacks: +405/-70
  • Gender: Male
    • My research history
Re: no bubbles in distillation of phenylacetone under vacuum
« Reply #1 on: December 03, 2012, 03:11:13 AM »
You mean 1-phenylpropan-2-one? If so it has a BPt. of 214-216°C at normal pressure.
So in your case I would get a better vacuum. Check everything for leaks, 100°C seems a bit high for the bath temp.
But in your case go for a better vacuum first.
Development Chemists do it on Scale, Research Chemists just do it!
My Research History

Offline shak22

  • New Member
  • **
  • Posts: 8
  • Mole Snacks: +0/-0
Re: no bubbles in distillation of hello, phenylacetone under vacuum
« Reply #2 on: December 03, 2012, 03:15:54 AM »
i have a vacuum pump with a vacuum gauge that state that my vacuum is at 20 torr, the temp that phenylacetone should evaporate under such vacuum is around 110-120c.
any other segestion?

Offline shak22

  • New Member
  • **
  • Posts: 8
  • Mole Snacks: +0/-0
Re: no bubbles in distillation of phenylacetone under vacuum
« Reply #3 on: December 03, 2012, 03:20:04 AM »
in addition,
i have done this at a higher temp and the matirial just went throw the condencer.. as a liquid..

Offline discodermolide

  • Chemist
  • Sr. Member
  • *
  • Posts: 5038
  • Mole Snacks: +405/-70
  • Gender: Male
    • My research history
Re: no bubbles in distillation of phenylacetone under vacuum
« Reply #4 on: December 03, 2012, 03:22:23 AM »
To be sure you did put 1-phenylpropan-2-one into the distillation apparatus?
Development Chemists do it on Scale, Research Chemists just do it!
My Research History

Offline shak22

  • New Member
  • **
  • Posts: 8
  • Mole Snacks: +0/-0
Re: no bubbles in distillation of phenylacetone under vacuum
« Reply #5 on: December 03, 2012, 03:23:05 AM »
yes

Offline shak22

  • New Member
  • **
  • Posts: 8
  • Mole Snacks: +0/-0
Re: no bubbles in distillation of phenylacetone under vacuum
« Reply #6 on: December 03, 2012, 03:23:41 AM »
it's basiclly a mixter..
somthing should be boiled...

Offline discodermolide

  • Chemist
  • Sr. Member
  • *
  • Posts: 5038
  • Mole Snacks: +405/-70
  • Gender: Male
    • My research history
Re: no bubbles in distillation of phenylacetone under vacuum
« Reply #7 on: December 03, 2012, 03:32:21 AM »
I take it the mixter = mixture?
I would dismantle the distillation apparatus and start again. Make sure all the joints are gas tight.

Development Chemists do it on Scale, Research Chemists just do it!
My Research History

Offline shak22

  • New Member
  • **
  • Posts: 8
  • Mole Snacks: +0/-0
Re: no bubbles in distillation of phenylacetone under vacuum
« Reply #8 on: December 03, 2012, 03:36:28 AM »
yes a mixture.
it's the third time i'm trying this...
any segestion?

Offline shak22

  • New Member
  • **
  • Posts: 8
  • Mole Snacks: +0/-0
Re: no bubbles in distillation of phenylacetone under vacuum
« Reply #9 on: December 03, 2012, 03:38:41 AM »
and i put silicone grease all over the joints..

Offline discodermolide

  • Chemist
  • Sr. Member
  • *
  • Posts: 5038
  • Mole Snacks: +405/-70
  • Gender: Male
    • My research history
Re: no bubbles in distillation of phenylacetone under vacuum
« Reply #10 on: December 03, 2012, 03:39:44 AM »
I take it that suggestion = suggestion.
What else is in the mixture?
My suggestion again: I would dismantle the distillation apparatus and start again. Make sure all the joints are gas tight.
Development Chemists do it on Scale, Research Chemists just do it!
My Research History

Offline shak22

  • New Member
  • **
  • Posts: 8
  • Mole Snacks: +0/-0
Re: no bubbles in distillation of phenylacetone under vacuum
« Reply #11 on: December 03, 2012, 03:45:28 AM »
some toleune and water - very little because i have disttiled them at normal disttilation

i realy can't figure this out.. i shold create some bubbles right?
thank you by the way!

Offline discodermolide

  • Chemist
  • Sr. Member
  • *
  • Posts: 5038
  • Mole Snacks: +405/-70
  • Gender: Male
    • My research history
Re: no bubbles in distillation of phenylacetone under vacuum
« Reply #12 on: December 03, 2012, 04:55:02 AM »
As I said, re-build the distillation apparatus and get a better vacuum.
Development Chemists do it on Scale, Research Chemists just do it!
My Research History

Sponsored Links