Hexavalent
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Urea Recrystallization
I recently heated up 700g of urea in 100ml of water to recrystallize it . . .but, soon after I smelt a strong odour of ammonia. What was going on
here?
"Success is going from failure to failure without loss of enthusiasm." Winston Churchill
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UnintentionalChaos
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Hydrolysis or formation of biuret. Some is probably unavoidable, keeping the temp lower will help, though recovery will not be as good (hey, urea is
dirt cheap anyway) I've had success in using alcohol/water mix to reduce the ridiculous solubility of urea in water, prevention the cooled solution
from resembling a brick.
Attachment: ureasolubility.pdf (283kB)
This file has been downloaded 2377 times
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'In organic synthesis, we call decomposition products "crap", however this is not a IUPAC approved nomenclature.' -Nicodem
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Hexavalent
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Thanks!!
I picked up 2kg of urea for 99p at a local discount store, sold for ice removal. As soon as I found its solubility data, I knew it was time to reach
for the big flasks
Is it possible, out of curiosity, that urea could generate hydrazine on its own?
"Success is going from failure to failure without loss of enthusiasm." Winston Churchill
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Hexavalent
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Also, what happens if I accidentally inhale some of the biuret? The MSDS isn't all that helpful. . .
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UnintentionalChaos
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Quote: Originally posted by Hexavalent  | Thanks!!
I picked up 2kg of urea for 99p at a local discount store, sold for ice removal. As soon as I found its solubility data, I knew it was time to reach
for the big flasks
Is it possible, out of curiosity, that urea could generate hydrazine on its own? |
no.
Biuret isn't particularly harmful unless you're a plant. Wikipedia would inform you that it is used as a non-protein nitrogen supplement for animals,
if you had bothered to read it.
Also, you see that little button in the top right hand corner of your posts that says "edit?" Use it.
For the multiposts you already made, click edit, check the little box that says "! Delete this message !" and hit edit post.
[Edited on 2-9-12 by UnintentionalChaos]
Department of Redundancy Department - Now with paperwork!
'In organic synthesis, we call decomposition products "crap", however this is not a IUPAC approved nomenclature.' -Nicodem
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Magpie
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see last post, this page:
http://www.sciencemadness.org/talk/viewthread.php?tid=7413#p...
The single most important condition for a successful synthesis is good mixing - Nicodem
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Hexavalent
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Thankyou UC and Magpie . . .I wasn't aware on how to delete double posts. Like the video on the Grignard reaction BTW UC.
"Success is going from failure to failure without loss of enthusiasm." Winston Churchill
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