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Paddywhacker
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Would fusing ferrocyanide or ferricyanide with KOH, or with KOH/NaOH eutectic mixture free up the cyanide to be distilled off as HCN with H2SO4?
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kmno4
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Quote: Originally posted by entropy51  |
How you figure 5.5 gm of distillate is 50% without titrating the CN?
Not bullshit, with CuCl I can get 80% of the CN from ferrocyanide. That's by titration.
It didn't work for you because your CuCN wasn't dissolved. |
I obtained this amount by collecting all vapour coming below 95 C.
Generally distillation stops at ~85 C (temp. of vapour) and I had to increase heating to force temperature rise.
I wanted to collect HCN, not H2O.
I posted here HCN-H2O diagram and this 5,5g is mainly HCN. That is why I wrote ~50 % not strictly 50% and in reality it is little less than 50%.
"It didn't work for you because your CuCN wasn't dissolved."
??
It did not work because it cannot work.
I use CuCl in my last experiment. I do not know what happens later - mixture is not homogenous. The only difference is colour (pinky), probably this
is caused by CuCN.
In conditions I presented, CuCN or CuCl has no effect on yield of HCN.
That is why I am still interested in conditions of your experiment with recovery of 80% CN from K4...
If you cannot give these conditions, we have nothing to discuss.
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entropy51
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| Quote: | | If you cannot give these conditions, we have nothing to discuss |
I used the procedure given in Brauer, scaled down to 10 gm of ferrocyanide and using twice as much H2SO4. One run without CuCl, one run with CuCl. I
used 0.6 gm CuCl dissolved in the minimum amount of 1:1 HCl. The HCN was absorbed in ice cold 1 N NaOH and an aliquot titrated with AgNO3 solution.
Since you have decided that it cannot work, discussion seems pointless.
I wonder why (or if) chemists would spend the money necessary to file a patent for a method that they know doesn't work.
[Edited on 4-10-2009 by entropy51]
[Edited on 4-10-2009 by entropy51]
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S.C. Wack
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The procedure that starts on the page that I linked to references his Chem. Ind. article, not the patent. If those aren't practical details, I don't
know what practical details are.
A 1929 article in Analyst describes the bullshitness of Williams thusly:
"Under the first head the cyanogen of the ferrocyanide is distilled off as hydrocyanic acid either by the method of W. Feld (J. Soc. Chem. Ind., 1903,
1068), in which the ferrocyanogen radicle is broken up by boiling with mercuric chloride and the cyanogen converted into mercuric cyanide, which is
then distilled with an acid; or by the method of H. E. Williams (J. Soc. Chem. Ind., 1912, 315), in which the ferrocyanide and acid is distilled with
a small quantity of cuprous chloride, the latter acting catalytically in breaking up the ferrocyanide and converting the cyanogen contents into
hydrocyanic acid.
The hydrocyanic acid evolved is absorbed into dilute caustic soda solution, and the resulting cyanide solution titrated with standard silver nitrate
solution after the addition of a few drops of a 10 per cent. solution of potassium iodide.
Both these methods are accurate if performed with care, but the results are liable to be somewhat low, particularly the former, owing
to the fact that slight losses may occur in the different operations, which are accumulative and appreciable when estimating material for 100 per
cent. purity.
They have the advantage that the cyanogen content is finally titrated by a solution which may be accurately standardised by known and accepted
methods, instead of by standardisation with what may or may not be pure ferrocyanide. On the other hand, while the cuprous chloride method is
comparatively simple, both methods require considerable skill and practice, and are therefore not suitable for general analytical practice."
If you're using the method for analysis, that is. Simply distilling off the HCN is a little simpler.
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entropy51
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| Quote: Originally posted by kmno4 |
I took 25g of K4[Fe(CN)6], 52g of 96% H2SO4, ~160g of H2O and 0,7g of CuCN (small granules, 1-2 mm).
After 5-hours heating (boiling) I still had lots of light green shit in a flask.....
Yield of NaCN: ~6g. A few grams remain in ethanolic/water solution (~200 ml) . So it is close to 50% recovery of cyanide from ferrocyanide.
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According to the paper by Adie and Browning posted abovethread, a dilute solution of H2SO4 such as this should give nearly 100% recovery of CN from
ferrocyanide, yet you only found 50%.
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kmno4
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| Quote: Originally posted by entropy51 | | Quote: Originally posted by kmno4 |
I took 25g of K4[Fe(CN)6], 52g of 96% H2SO4, ~160g of H2O and 0,7g of CuCN (small granules, 1-2 mm).
After 5-hours heating (boiling) I still had lots of light green shit in a flask.....
Yield of NaCN: ~6g. A few grams remain in ethanolic/water solution (~200 ml) . So it is close to 50% recovery of cyanide from ferrocyanide.
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According to the paper by Adie and Browning posted abovethread, a dilute solution of H2SO4 such as this should give nearly 100% recovery of CN from
ferrocyanide, yet you only found 50%. |
I know what I obtained. I also posted this article. I also know what is written there. But I cannot find this "according".
Could you post some attachment or citation where recovery of near 100% of CN can be obtained when reagents are used in proportions given above ?
| Quote: Originally posted by S.C. Wack |
The procedure that starts on the page that I linked to references his Chem. Ind. article, not the patent. If those aren't practical details, I don't
know what practical details are.
A 1929 article in Analyst describes the bullshitness of Williams thusly: (...) |
| Quote: Originally posted by kmno4 | | Volume ~130 ml, 0,5g K4..... and ~48-fold mole excess of H2SO4 is not interesting for me. On this proportions it works also without any Cu
salt, as it is described in previously cited paper from JChemSoc. |
Paper by Adie and Browning of course 
I have read many articles about "analytical decomposition" of ferrocyanides. In some article is given reference and its authors investigate various
salts for this purpose and most active are salts of : Pt, Pd, Ag, Hg... but Cu is not even mantioned. Unfortunately, this reference (in german) is
unavailable in electronic form.
[Edited on 5-10-2009 by kmno4]
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entropy51
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| Quote: | But I cannot find this "according".
Could you post some attachment or citation where recovery of near 100% of CN can be obtained when reagents are used in proportions given above ?
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Compare your H2SO4 concentration to the table on page 154 of Adie and Browning, specifically the column labelled "HCN (calc as 6HCN per mol.
K4Fe(CN)6) which corresponds to your reaction conditions (sulfuric conc and reaction time). Your sulfuric concentration looks like approximately
H2SO4 17H2O in their terminology (molar ratio). You distilled for 5 hours. Their yield of HCN for those conditions is 98 or 99% of 6HCN from their
table. Thus your yield seems only about half that of Adie and Browning.
Thus my use of the word "according", which I think is fairly accurate.
I was just wondering if you had noticed that, but I guess you had not compared your result to theirs.
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kmno4
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| Quote: Originally posted by entropy51 | | Quote: | But I cannot find this "according".
Could you post some attachment or citation where recovery of near 100% of CN can be obtained when reagents are used in proportions given above ?
|
Compare your H2SO4 concentration to the table on page 154 of Adie and Browning, specifically the column labelled "HCN (calc as 6HCN per mol.
K4Fe(CN)6) which corresponds to your reaction conditions (sulfuric conc and reaction time). Your sulfuric concentration looks like approximately
H2SO4 17H2O in their terminology (molar ratio). You distilled for 5 hours. Their yield of HCN for those conditions is 98 or 99% of 6HCN from their
table. Thus your yield seems only about half that of Adie and Browning.
Thus my use of the word "according", which I think is fairly accurate.
I was just wondering if you had noticed that, but I guess you had not compared your result to theirs.
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I knew that you recall table on 154 page 
You have missed one very important thing (missing) in this article.
I give you 2 days for reading this article as many times as it is necessary for fully understanding why you cannot compare their results to my
results.
Have a nice reading.
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entropy51
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| Quote: Originally posted by kmno4 | [I knew that you recall table on 154 page
You have missed one very important thing (missing) in this article.
I give you 2 days for reading this article as many times as it is necessary for fully understanding why you cannot compare their results to my
results.
Have a nice reading.
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I don't need to read the article again to understand what you did differently. They had glassware and
chemicals and actually performed an experiment. On the other hand, I've seen your fantastic equipment here and dodgy reports.
I did my homework asignments when I was in school. Now that I've had my doctorate since before you were born, I don't need homework assignments from
wee lads like you. Find some kids your own age to play games with. I hope you had a nice reading.
[Edited on 6-10-2009 by entropy51]
[Edited on 7-10-2009 by entropy51]
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kmno4
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Wow. Doctor. Fenced doctor. I know such doctors very well 
I am almost going down on my knees saying " I am sorry for my experiments".
"I've seen your fantastic equipment here and dodgy reports"
My equipment seems not fantastic to me and I am sorry that you cannot afford for equally good one. Dodgy reports - I report (from time to time)
effects of my experiments, that is all.
Unfortunately no-one else wants to report effects of H2SO4/K4... experiments. Effects determined by weight, not by visual observations.
As I see, you were too lazy to do your homework, although you had two days and only 11 pages of reading
The table on p. 154 contains a summary of the results obtained, using as neariy as possible the same weight of potassium ferrocyanide and
a large excess of sulphuric acid, so as to keep the concentration of the acid nearly constant.
This is very important note from page 6 of mentioned article.
Because of unknown (but large) amount of H2SO4 solution, reported results are almost useless. The only information is that the larger dilution of
H2SO4, the larger extent of K4... decomposition, under condition of large excess of acid solution.
This is very similar to "analytical" procedures posted earlier but not to procedures which I implemented.
End of homework.
ps. you have mentioned procedure from Brauer with 10g of K4... x3H2O and twice H2SO4.
So I am going to try this: 20g K4... x3H2O, 32g H2SO4 (96%), 25g H2O, 1,2g CuCl in minimal amount of 1:1 HCl.
Then I will see if you are a plain liar (like I suspect) or not.
Of course I will post my dodgy results here 
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watson.fawkes
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| Quote: Originally posted by kmno4 | | As I see, you were too lazy to do your homework, although you had two days and only 11 pages of reading |
Pardon my interruption, but you're acting the ass here, just like that
fellow who was all up about ORMUS a few months ago. In both your case and his, you somehow seem to think that the responsibility for proving claims
relies on someone else other than you. The difference, admittedly, is that you can eventually do so and he can't. Nonetheless, the more important of
these, the taking of responsibility, is the one you've failed at. You've achieved no moral high ground, rather instead painting yourself as somewhat
delusional about your own status.
So just stop, and let it pass as a folly, hopefully of youth.
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entropy51
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| Quote: Originally posted by kmno4 | | Unfortunately no-one else wants to report effects of H2SO4/K4... experiments. Effects determined by weight, not by visual observations.
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Ok, you weighed something, but what was it?
OK, you think it was HCN, but was it
really?
| Quote: Originally posted by kmno4 | Solution should be heated up to boiling. In r.t. or even warmer, reaction is very slow.
Green precipitate (FeK2[Fe(CN)6]), turning blue on air is normal thing. It very, really very slowly reacts with H2SO4 even on boiling.
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So you heated an aqueous solution to boiling and distilled something out, and you just
know that it was mainly HCN and you determined your yield by weighing it? I captured HCN in cold aqueous NaOH and titrated it with
AgNO3 using the standard procedure.
And you have the nerve to call me a liar?
[Edited on 9-10-2009 by entropy51]
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kmno4
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Sorry, I do not understand this gibberish but it seems to have nothing with "preparation of cyanides". If you have something to say to me personally,
do it via U2U.
To entropy51:
I am not going to discuss with you in this way, beacuse you can find answers for all these questions, in this thread. I am not going to quote myself
for eternity. My posts are clear enough even for "doctors".
[Edited on 9-10-2009 by kmno4]
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watson.fawkes
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| Quote: Originally posted by kmno4 | | Sorry, I do not understand this gibberish but it seems to have nothing with "preparation of cyanides". If you have something to say to me personally,
do it via U2U. |
My condolences that you don't understand what "acting the ass" means, and no, I won't do this
in private. You've been demanding that other people confirm whatever it is you've been doing. This is counter to the way that science works, which is
that people who claim something carry the burden of proof. If you are unwilling or unable to carry the burden of proof, then don't make such claims in
the first place.
Your challenger is not an idiot and has legitimate concerns about your experimental procedure. Rather than answer these concerns or concede them,
you've gotten defensive, which I have previously ignored. You crossed the line when you demanded that someone else take undue effort and then
upbraided them for not doing so. That is the veritable territory of cranks. And this is the reason that this is in public, that this kind of behavior
is not respectable, and you have earned my disrespect.
If someone has a concern about something you've claimed, then you answer it. If you've already answered the exact question, such that reading a
single previous answer is sufficient, then you may answer by reference. Otherwise, even when there is partial overlap in a previous question,
then you partially repeat myself. It is not the obligation of a questioner to defend your claim and convince themselves. It is your responsibility.
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entropy51
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| Quote: Originally posted by kmno4 | | [I am not going to discuss with you in this way, beacuse you can find answers for all these questions, in this thread. I am not going to quote myself
for eternity. My posts are clear enough... |
Reality check:
The only diagram posted by kmno4 in this thread
(he did say "this thread") is a plot of pH vs HCN/CN- which says nothing about how much (if any) HCN is contained in his distillate. So weighing the
distillate proves nothing.
| Quote: Originally posted by kmno4 | I think that the only way to obtain pure (>98%) cyjanides is introducing mixture HCN+H2O to akoholic solution KOH or NaOH. I have made many grams
of KCN using this methode (more than 1kg  )
Mixture HCN/H2O was obtained by heating K4[Fe(CN)6]+H2O+H2SO4 or H3PO4. Both acids work good and concentration(%) has no special meaning: 30%-60% is
ok.
Reaction is:
2K4[Fe(CN)6]+3H2SO4 -> 6HCN + FeK2[Fe(CN)6]+3K2SO4
With a simple distilling aparaturus, during haeting, at about 50*C (temperature of vapors) the mixture HCN/H2O starts to evolute, and after
condesation it is introduced into KOH/C2H5OH solution.
KCN starts to precipitate,the solution is getting warm, but there is no need to to cool it. This mixture MUST be continual stirrig by magnetic
stirrer - in another case a "cake" is collecting at the surface and there is no full reaction between HCN and KOH - it is a little dangerous.
The distillation is interputted at about 95*C - just too many water is then evoluted. |
But in this post,
kmno4 says that if you heat above 95 that too much water comes over! And he says that HCN/H2O distills! Not mainly HCN.
This is inconsistent with his earlier claim that his distillate is "mainly HCN". Kmno4 does have nerve claiming that he's the only one who has
posted solid claims.
Kmno4 says that the concentration of H2SO4 has no influence on CN yield, but we do know better than that don't we? Based on the Adie and Brown
article that kmno4 assigned as my homework.
How could anyone make sense out of kmno4's inconsistent and dodgy posts?
Kmno4 seems to have a surplus of mouth until someone points out his egregious errors, then he shuts up.
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kmno4
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I have just done experiment according to Brauer, with double amount of H2SO4, 20g K4...x3H2O + 2g CuCl in 1:1 HCl (~10 cm3).
Results are very interesting but predictable, according to literature.
After 4 hours boiling less than 0,8 g of low-boiling condensate was colected.
Reaction was very slow and few last droplets of condensate were colored. Loss of weight of input material was almost the same.
Now I am sure that entropy51 is just a liar, like I suspected from the very beginning
He has never even touched equipment to test this reaction, with or without CuCl or any other shitty catalyst. His only contribution to this thread is
entropy and noise.
That is all I have to say in question of Doctor Entropy and Cu salts. And patents about it.
* liquid-vapour diagram for HCN-H2O is available from Ullmann's Encyclopedia in "Cyanides" chapter. I posted this picture here long time ago but now
it's gone ( probably I removed it)
** at last I got standard sample of AgNO3 and titrated freshly prepared and dried NaCN. Result was a pleasure: 99.6 %. My old sample of NaCN gave
95,6%.
[Edited on 12-10-2009 by kmno4]
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entropy51
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The Scientific Method
(according to kmno4)
1. All patents are bullshit
2. Peer-reviewed literature is to be taken with grain of salt
3. Anybody who questions his methodology is to be given a homework assignment.
4. If he cannot reproduce their results, they are liars.
5. One of his experiments is worth ten of anybody elses.
6. If anybody asks for details, he says he has already told that many times.
7. His distillations give the product that he says they do, even if he said they give something else another time.
8. His $ 12 scale is better than any foolish titration.
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entropy51
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| Quote: Originally posted by kmno4 | | at last I got standard sample of AgNO3 and titrated freshly prepared and dried NaCN. Result was a pleasure: 99.6 %. |
Congratulations on your pleasure. Other chemists on the forum have found their samples to titrate at 85%. There is usually some Na2CO3 contamination
from atmospheric CO2 and sometimes the reaction itself gives CO and CO2. Somebody may be lying again!
| Quote: | | I am not going to discuss with you in this way, beacuse you can find answers for all these questions, in this thread. I am not going to quote myself
for eternity. |
Now you see it, now you dont! | Quote: Originally posted by kmno4 | liquid-vapour diagram for HCN-H2O is available from Ullmann's Encyclopedia in "Cyanides" chapter. I posted this picture here long time ago but
now it's gone ( probably I removed it)
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More magic tricks by the Amazing Purple One.
[Edited on 13-10-2009 by entropy51]
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UnintentionalChaos
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| Quote: Originally posted by entropy51 | | Quote: Originally posted by kmno4 | | at last I got standard sample of AgNO3 and titrated freshly prepared and dried NaCN. Result was a pleasure: 99.6 %. |
Congratulations on your pleasure. Other chemists on the forum have found their samples to titrate at 85%. There is usually some Na2CO3 contamination
from atmospheric CO2 and sometimes the reaction itself gives CO and CO2. Somebody may be lying again!
| Quote: | | I am not going to discuss with you in this way, beacuse you can find answers for all these questions, in this thread. I am not going to quote myself
for eternity. |
Now you see it, now you dont! | Quote: Originally posted by kmno4 | liquid-vapour diagram for HCN-H2O is available from Ullmann's Encyclopedia in "Cyanides" chapter. I posted this picture here long time ago but
now it's gone ( probably I removed it)
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More magic tricks by the Amazing Purple One.
[Edited on 13-10-2009 by entropy51] |
Do us all a favor. Next time you feel the need to type, let it go.
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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entropy51
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Us? All?
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Engager
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Recently i've found interesting method to produce cyanide without too high temperatures or HCN involved. This simple process was discovered by
Playfair and even was offered for idustial use:
Then Playfair tried the use of metals at first lead and zinc, for these only appeared suitable. The metals decomposed the sulphocyanide either in
fusion or in solution according to the reaction
KSCN + Zn = ZnS + KCN
After many experiments, Playfair adopted the following procedure : He used a receiver made of black lead, whose form is that of an inverted muffle and
which is provided with a tightly fitting lid. This apparatus is placed in a furnace in such a way that the top of the receiver extends 2 to 5
centimeters above the upper border of the furnace so that it becomes heated only at the bottom and the sides. Zinc is then melted in the presence of a
small quantity of pulverized charcoal, which maintains a reducing atmosphere in the crucible. When the zinc is completely fused dry sulphocyanide is
added, either cold or even in a melted state.
The mass is kept stirred and the reaction continued till the mass becomes quite thick and begins to redden. At this point the reaction is complete.
The mass is then allowed to cool, protected from the air. When cold, the mass is easily removed from the crucible, which does not appear at all
attacked. The color of the mass should be pearly gray, if the reaction has been successful, in which case its solution will be entirely free of
soluble sulphides. But if the mass has been superheated, which happens especially when too large crucibles are used, it has a brownish and sometimes
even a reddish color, and the solution may contain as much as 15% of alkaline sulphide.
As a rule one must assume a loss of about 5%, due partly to moisture and partly to the formation of small quantities of cyanate and carbonate. One
should add also to the above loss that which may result from the formation of the double cyanide of zinc and potassium or sodium in consequence of a
too high temperature, but this loss may be easily avoided by the use of a slight excess of sulphocyanide.
The melted mass is subjected to a systematic lixiviation in a series of vats. The alkaline cyanide solution is separated from the insoluble zinc
sulphide by decantation. This latter substance constitutes about 65% of the fused mass. The solutions thus obtained vary considerably in
concentration; that is, from 4 grams of sodium cyanide per liter to 220-240 grams. These latter solutions are evaporated in vacuum to the consistency
of a thick paste, which on cooling crystallize. The following is an analysis, made by Playfair, of one of these solutions. The figures represent the
amounts per 100 cc. of solution to be evaporated.
Sodium cyanide 22.00 gm.
Cyanate 3.06
Double cyanide of zinc and sodium 1.55
Sodium carbonate 0.71
Sodium sulphocyanide 1.80
Playf air's process marks a real progress; it can be applied industrially, since, according to the inventor, the yield is about 70% of the theoretical
amount. This result is obtained if care be taken to concentrate the solutions in a vacuum of 66 centimeters, using solutions containing at least 22%
of cyanide, so as to avoid loss of cyanogen.
Dr. Hans Luttke's Process. This process is based on the same principle. It consists in melting sulphocyanide with zinc powder. In an iron crucible are
fused together
97 kg. sulphocyanide of potassium,
65 zinc powder.
The mass is stirred while being heated, and from the moment it fuses, the crucible is removed from the fire. The reaction then goes on by itself. When
the fused mass is treated with water it yields about 60 kg, of cyanide, i.e., 90% of the theoretical amount. The sulphide of zinc which is obtained as
a by-product may be profitably used as a mineral color.
The reaction takes place between 360 and 400; this temperature may be lowered by an addition of 1% to 2% caustic alkali, which at the same time,
increases the yield of cyanide.
Various other metals have been tried. Lead, which was also recommended by Playfair, has the advantage of not forming double cyanide of lead and
potassium, but on account of its high atomic weight, three times as much lead as zinc are required to perform the same work, while, at the same time,
it has a tendency of falling to the bottom of the crucible without remaining mixed with the sulphocyanide.
The reduction of sulphocyanide may be well carried on with the use of tin, but tin sulphide dissolves in rather appreciable quantities in the alkaline
cyanide. The use of copper is no more successful, for it gives rise to cuprocyanides.
[Edited on 20-10-2009 by Engager]
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Engager
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Now some personal experience. I've prepared mixture from 32g zinc dust and 5g of finely grounded charcoal, those are added to fused 50g of potassium
thyocyanate (KSCN). Addition was carried out by portions with stirring. After all zinc has been added iron crucible was heated further using flame
from propane gas oven, with eventual mixing. After some time mixture begun to increase it's volume showing some very slight foaming, heating was
continued, mixture was setteled down and gradualy begun to thicken, at this moment bottom of the crucible was at red heat. Then mixture almost
solidified, heat source was shut down and mixture is allowed to cool, then crushed to lumps and liquified with 100 ml of warm water. Lumps we quickly
dissolved leaving black solution containing large ammount of solid (some unreacted charcoal and zinc sulphide), it was filtered to obtain very
slightly yellowish solution with strong alkaline reaction. Sample of solution was tested for presence of cyanide by double decomposition with zinc
chloride, imidately after mixing amorphous precipitate of zinc cyanide was precipitated from solution (zinc thyocyanate is perfectly soluble so not
gives precipitate in same test). To differ precipitate with grey zinc sulphide witch can also precipitate due to sulphides present in product
solution, excess of product solution is added to solid sample - most of it dissolved due to formation of soluble zinc-potassium double cyanide,
showing that some small of sulphide present, but solution contained mainly potassium cyanide.
[Edited on 20-10-2009 by Engager]
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entropy51
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Interesting prep, Engager. Have you tried something quantitative such as titration to see how much KCN is in the product? Thanks.
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halogenstruck
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if it works then
why not this:
NaCNO+Zn--->NaCN+ZnO
or NaCNO+C--->NaCN+CO
ACTUALLY when u heat KNO3& C then U have NaCNO at first step then is reduced to NaCN
and sodium cyanate can be made from just urea
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Jor
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I will give this a try when I'm home. Shame I have only a few tens of grams of KSCN, and I have zinc shavings only, but as it will melt in the
progress it shouldn't matter.
However, I will extract the KCN with methanol, it dissolves about 5g per 100mL at 20C. Much easier.
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