anticoplanar
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RFC - Steam Distillation Apparatus Construction
Would anyone be able to comment on adding an inlet/bleed to a round bottom flask with pyrex tubing? I'd like to be able to run steam into my 24/40
kit.. possibly draw it out for vacuum as well?
Just kind of throwing it out there.
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Magpie
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I use a 3-neck flask for steam distillation. The side necks are angled which allows the centering of the steam injector nozzle at the flask bottom.
The injector is a 6mm glass tube held in place with a thermometer adaptor. A 2-neck flask with angled side port would work just as well.
Adapting a single port RBF for steam distillation would get a little tricky. Probably could be done using a Claisen adaptor, however.
The single most important condition for a successful synthesis is good mixing - Nicodem
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anticoplanar
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Exactly a great solution. Thanks.
Happen to have that same glass, maybe even.
[Edited on 29-3-2007 by anticoplanar]
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Furch
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It's also doable to just drip water onto the pre-heated (above 100 C) substrate, through for instance the three-way adapter, or a claisen adapter.
Steam is evolved, and it will bring the steam distillable substrate with it. This is an option for people who don't have multi-necked RBF's.
\"Those who say do not know, those who know do not say.\" -Lao Tzu
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seb
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What you are talking about is external steam generation, according to the organic lab course manuals. Internal steam generation involves having an
aqueous mixture present, and you reheat it, say in the case of a based-over meth rxn w/ HI/P once you've filtered out the P and carefully added 50%
NaOH to a cooled rxn mixture. I recommend external, with the 6mm glass tube held into a second port w/ a thermo adapter,...but, actually I don't.
Those are rubber and I never let rubber around meth base, or iodine. I use cork instead of rubber. A "24/40 cork" is a common size. The steam, if
supplied by a Hot Shot boiler (eBay), will drive over all the product in minutes, clean. Use a 6L sep funnel as a receiver, and use two 200mm West
condensers w/ a bent adapter at one end and a 105-degree elbow at the other. The sep funnel's stopcock should protrude out the bottom of the ice
chest so it doesn't get cold and shrink and you lose all the product that way. This is someone who is me; I already have convictions. I am using the
present tense for ease of communication.
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MARXYZ
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I recently purchased a a steam cleaner. It is built like a coffee pot with a push button to release the steam. Hypothetically, if one were to place
the external steam machine above the level of the flask holding the heated reaction medium, and port the steam to the top of the flash, and not below
the surface of the liquid (suck back prevention), and provide a port for distillation (I prefer a vertical condenser), one has the perfect setup.
It provides fingertip control of very hot and dry steam. It turns steam distillation to a fast high yielding process. I have found my perfect source
of external steam generation!
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stoichiometric_steve
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| Quote: | | Originally posted by MARXYZypothetically, if one were to place the external steam machine above the level of the flask holding the heated
reaction medium, and port the steam to the top of the flash, and not below the surface of the liquid (suck back prevention), and provide a port for
distillation (I prefer a vertical condenser), one has the perfect setup. |
i think all you get that way is a lot of condensed water vapour, and just that. the steam has to bubble THROUGH the compound to be distilled.
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