Hexavalent
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Sodium Dichloroisocyanurate
I have recently, very cheaply, purchased some water purification tablets that contain only sodium dichloroisocyanurate and an insoluble binder. Anyone
have any ideas on how to convert them into;
a) dichloroisocyanuric acid
b) isocyanuric acid??
"Success is going from failure to failure without loss of enthusiasm." Winston Churchill
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MrTechGuy1995
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What I've been lead to believe, that if you add HCl, which lowers the pH, will remove the Cl- to for Cl2 and the Na+ to NaCl, which leaves the
Isocyanuric acid. I don't remember where I found that. If I recall it's nurdrage's chlorine gas video, that he put onto private. But I can't be sure.
From there when you have Cyanuric acid. Bubble in the Cl2 to form DiChloroisocyanuric acid. //Wikipedia
I am also not sure if you should recycle the off coming Cl2 from the first reaction with HCl. The NaCl May react with the Cyanuric to for Cyanurate
again.
Please correct me if I made any mistakes.
[Edited on 23-1-2012 by MrTechGuy1995]
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woelen
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Isocyanuric acid can easily be made. First crush the tablets and add water. The sodium dichloroisocyanurate dissolves and the binder remains behind.
Filter the solution such that you get a clear solution. To this clear solution add concentrated hydrochloric acid (this will produce chlorine gas and
a lot of insoluble matter, which is the isocyanuric acid) and boil the solution until it becomes clear. Allow to cool down. Crystals of isocyanuaric
acid will separate from the liquid. This compound can very easily be crystallized from water. In boiling water it dissolves quite well, while it is
nearly insoluble in cold water.
Making dichloroisocyanuric acid is a lot more difficult. Bubbling chlorine through a solution of cyanuric acid will not work. I think you may have
more luck if you carefully add dilute nitric acid or dilute sulphuric acid (NOT hydrochloric acid) to a solution of sodium dichloroisocyanurate in
water. The dichloroisocyanuric acid is much less soluble than the sodium salt of this acid and you may get a precipitate of this acid. Just try it on
a small scale to see whether this works or not.
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Hexavalent
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Great, thanks. That was what I had in mind, seeing as pthalic acid can be made from disodium phthalate this way also. But, in this case, I was just
concerned about the evolution of HCN.
"Success is going from failure to failure without loss of enthusiasm." Winston Churchill
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UnintentionalChaos
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Quote: Originally posted by Hexavalent  | | Great, thanks. That was what I had in mind, seeing as pthalic acid can be made from disodium phthalate this way also. But, in this case, I was just
concerned about the evolution of HCN. |
Huh...Cyanuric...if anything, it would decompose to cyanic acid (HOCN) but you need to roast it for that to happen. It is very happy as the trimer.
I don't know why you'd want dichloroisocyanuric acid. I can't really imagine any uses. You'd be better off just converting it to TCCA by bubbling
chlorine through the solution of the sodium salt. TCCA is less soluble and should precipitate in fairly high yield. You could even use the chlorine
from the material you want to turn into cyanuric acid.
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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