Pages: 1

Author Topic: Sodium Cyanate  (Read 101 times)

Happyman

  • Subordinate Wasp
  • ***
  • Posts: 122
Sodium Cyanate
« on: July 07, 2009, 11:57:51 PM »
Please check my chemistry  :)

1 mole Urea+1 mole Lye=1 mole Sodium Cyanate+1 mole water+1 mole Ammonia
(NH2)2CO(aq)+NaOH(aq)=NaOCN(s)+H2O(l)+NH3(g)

Thanks.

nk40ouvm

  • Pupae
  • **
  • Posts: 73
Re: Sodium Cyanate
« Reply #1 on: July 08, 2009, 12:32:57 AM »
I don't know if it will actually play out like that. Every urea -> cyanate prep I have seen intimately mixes the alkali metal compound (usually carbonate, bicarbonate is better due to lower water affinity) with urea while dry, then carefully heats to fusion.

Why not use a prep from Inorganic Syntheses or any of many other highly similar inorganic books? They're well documented and use even cheaper materials than what you've proposed.

Edit: I guess I should say you are better off searching for "potassium cyanate" preparation on e.g. Google Books and then substitute an appropriate sodium compound if you really need sodium cyanate. Most preps seem to be for the potassium compound, possibly because of historical reasons or the solubility of the potassium salt.

Here is a book from the SM library that contains explicit preps for both the potassium and sodium compounds.
« Last Edit: July 08, 2009, 12:48:35 AM by nk40ouvm »

Sedit

  • Global Moderator
  • Foundress Queen
  • *****
  • Posts: 2,099
Re: Sodium Cyanate
« Reply #2 on: July 08, 2009, 03:20:14 AM »
Happy, you where the one that wanted to perform the Chlorination of toluene correct?

If Im not mistaken Cyanic acid is the by product of the reaction and if that was neutralized with NaOH it would yeild you your sodium cyanate. Someone can correct me here if im wrong but im pretty sure thats what you would get.

I think you need to go get some of that TCCA Happy. Dirt cheep and kill two birds with one stone.
There once were some bees and you took all there stuff!
You pissed off the wasp now enough is enough!!!

nk40ouvm

  • Pupae
  • **
  • Posts: 73
Re: Sodium Cyanate
« Reply #3 on: July 08, 2009, 04:14:54 AM »
The byproduct is cyanuric acid, the trimer of cyanic acid. According to patents it can be used much like urea for preparing cyanates (grind dry together, then fuse). I've never seen any academic literature about preparing cyanates from cyanuric acid but it seems perfectly plausible given that there is well documented literature about distilling cyanuric acid to monomeric cyanic acid.

Happyman

  • Subordinate Wasp
  • ***
  • Posts: 122
Re: Sodium Cyanate
« Reply #4 on: July 08, 2009, 04:49:37 AM »
Omg. Genius. Unfortunately I only see Dichloroisocyanuric acid but I assuming that will still work?
2C7H8(l)+C3HCl2N3O3(s)=2C7H7Cl(l)+C3H3N3O3(s)
But this reaction to sodium cyanate seems funny. I'm positive that I messed something up.
C3H3N3O3(s)+3NaOH(aq)=3NaOCN(s)+H2O(l)+H2(g)

Vesp

  • Administrator
  • Foundress Queen
  • *****
  • Posts: 3,130
Re: Sodium Cyanate
« Reply #5 on: July 08, 2009, 09:38:08 AM »
If it is sodium cyanate you need, you shouldn't have any problems making it in a relatively pure form from urea and a carbonate, bicarbonate, or hydroxide using a molar ratio

I'd just dissolve 1 mol of urea with 1 mol of sodium bicarbonate in water boil away if I needed it. The ammonia, carbon dioxide and water would form and leave as you boiled it. You could then do some crystallizations to get it pure if you think you have any impurities that you need to worry about.


Just as a side note... NaCN can be made from NaOCN + C IIRC.



Bitcoin address: 1FVrHdXJBr6Z9uhtiQKy4g7c7yHtGKjyLy
Pages: 1