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Author: Subject: Inhibiting Foaming During Distillation
crestind
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[*] posted on 14-2-2013 at 23:48
Inhibiting Foaming During Distillation


I have a very basic distillation kit like the one shown here.
http://www.glasswaresforlab.com/cmtimages/glass_distillation...

How can I prevent foaming during distillation without adding chemicals to the mix? I probably need some sort of 90 degree angled stirring device to break up the foam or maybe some sort of filter. I know what I need, but I don't know the specific name of the apparatus I'm searching for.
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crazyboy
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[*] posted on 14-2-2013 at 23:56


Usually I find magnetic stirring works to break up foam, failing that take it easy on the heating. If it just keeps foaming take a look at this http://en.wikipedia.org/wiki/Defoamer. Maybe add some silicone oil to the reaction to break the surface tension.

What reaction is this by the way?




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Hexavalent
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[*] posted on 15-2-2013 at 01:42


In professional labs, special anti-foaming agernts are added to the reaction mix. However, these can be difficult to procure, so, if I'm ever faced with foam, I try the following:

-Use a vigreux column
-Add a drop of washing up liquid to break surface tensions
-As aforementioned, use magnetic stirring
-Finally, just let the foam go - collect the distillate you get, and then re-distill it again (this time, there is usually no foam or it is minimal).




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Bot0nist
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[*] posted on 15-2-2013 at 06:24


IIRC, baby's anti-gas drops can be used to success if it wont interfear with the reaction/seperation. I believe I read it in one of peach's writeups. I'm going to hunt for it now.



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crestind
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[*] posted on 15-2-2013 at 14:40


It's an organic solution with lots of dissolved salts, proteins, sugar, etc. That's why it foams.
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