I read almost all the topic of the forum ( the title at least) and i didn't found any recipe for making K or Na Cyanide.
I found this recipe for sodium cyanide in the book edited by NBK2000 and i would like to know if it look like good or not.
The ferrocyanide recipe is not very important because ferrocyanide is easy to obtain.
I will not do any stupid things with that, just want to kown. It looks like so easy. Little bit scary isn't it ?
Here it is:
Ferrocyanide Prepatation
Ferrocyanide is obtained by heating 10 parts (by weight) potassium (or sodium) carbonate; 10 parts coke. cinders, or coal; and 3 parts iron turnings,
all in coarse powder. to a full red heat in an open crucible, stirring occasionally until small jets of purple flame arc no longer seen. When cool,
the soluble matter is dissolved out of it, the solution filtered, evaporated, and crystallized. The crystals obtained are redissolved in hot water and
cooled very slowly, forming large yellow crystals of the ferrocyanide. In order to obtain a pure form, melt dried ferrocyanide in a glass vessel and
let cool, dissolve the fused mass in water, neutralize any excess of alkali with acetic acid (vinegar), and precipitate the salt by adding strong
alcohol to the solution. Wash the precipitate with a little weak alcohol, redissolve it in water, and crystallize.
Cyanide Preparation
To convert the ferro to cyanide do this (please note that these instructions were for the potassium not sodium salt. I'm assuming that the ratios are
similar for both); Mix thoroughly 8 parts of dry sodium ferrocyanide and 3 parts dry sodium carbonate (pool pH adjuster), heat them in a steel
container (cleaned oil filter can works nicely), with constant stirring (use clothes hanger, straightened out), with a propane torch or other intense
heat source till it melts into a clear liquid. Heating is continued until the mix no longer fizzes and the fluid portion is colorless. After a few
minutes rest, to allow the contents to settle, the clear portion is poured from the heavy black sediment (iron) at the bottom at the bottom of the
crucible and onto to a clean slab or steel bowl. It's then broken up while still warm and stored in airtight bottles. This will be almost pure
cyanide.
ThanksSauron - 23-12-2008 at 13:23
"Recipe" ???
This is inorganic, not organic chemistry.
[Edited on 24-12-2008 by Sauron]Nicodem - 24-12-2008 at 05:02
Quote:
Originally posted by vassili78
I read almost all the topic of the forum ( the title at least) and i didn't found any recipe for making K or Na Cyanide.
You must be joking! There is an enormous thread discussing all possible ways to sodium, potassium or hydrogen cyanides. How did you manage to miss it?
It also includes the preparations starting from potassium ferrocyanide or ferricyanide. UTFSE! (Also, you better stop using the word "recipe" since it
makes members here very nervous. Rather use proper chemical terminology.)
Quote:
I will not do any stupid things with that, just want to kown. It looks like so easy. Little bit scary isn't it ?
It does not look easy, it just looks dumb. I'm not an inorganic chemists but there is very little that makes sense in the procedures you posted. The
chances that any cyanide could be obtained by the carbonate + N2 + C reaction with air as the source of nitrogen, which is 21% oxygen anyway, is
negligible. The old industrial process used a mixture of nitrogen and carbon oxides (and certainly not an open vessel).
Also, I do not know if or how is potassium/sodium ferrocyanide supposed to react with K2CO3/Na2CO3, but I'm sure in no case is iron going to be
produced. Chances are that heating potassium carbonate with potassium ferrocyanide gives also some cyanides and iron carbonates/oxides (I do not
know), but the mixture obtained will be far from pure KCN. This would have to be isolated.
I suggest you to rather check the scientific literature for these reactions and most certainly also read the thread on cyanides.
[Edited on 24/12/2008 by Nicodem]vassili78 - 24-12-2008 at 07:50
Thanks you Nicodem for your complete answer.
An so easily synthesis for cyanide was very suspect. Just mix 2 product and "hop".
I will check the topics of the forum to find the one which talk about that.
Sorry for this unsuseful topic.vassili78 - 24-12-2008 at 07:54
yes indeed, huge topic on cyanides... S.C. Wack - 24-12-2008 at 09:45
It sounds like Anarchists Cookbook material so it shouldn't be surprising that a recipe is asked for.
This is a well known reaction and was the major source of cyanide for a time. There is no question that it produces metallic Fe and KCN, but also
cyanate. However, there are other shining points of fail as written: using the hydrated (yellow) salt that would be formed if ferrocyanide was
recrystallized from water, or using a crucible open to air.grind - 24-12-2008 at 13:58
Quote:
Originally posted by vassili78
In order to obtain a pure form, melt dried ferrocyanid
In my experience potassium ferrocyanide does not melt as such, but decomposes when heated, in a molten state KCN has formed.
Equation:
