Preparation of cyanides

Quote: Originally posted by mario840

what is wrong with this recipe ?? tell me what exactly

Quote: Originally posted by watson.fawkes

Quote: Originally posted by mario840   If you insist on making toxic chemicals with procedures from suspect sources the best part is suspect sources ... these sources base on patent and inorganic preparatory not only in english, others country still has book in their languages , (the same amounts and the same concentration of H2SO4 which evolute hcn instead of cyan (CN)2 )... if you have brain and learn quick and read not only one book you can confirm "suspect" recipe , so guy enropy51 said these is crap , hmmmm very interesting so the patant and recipe from other books and work others member of these forum are also crap , i don't insist anybody to do ANY toxic chemical but the topic is about cyanide so i posted here in my opinion very good synthesis of it and confirming with others recipe it works, just read page nr. 4 (LD NaCl = 250 g so don't do NaCl !!!! )

red ferro

kcn

taoiseach ,to each his own?

cyanureeves what can i say I HEARD this synthesis fucking rox , need low energy (boiling water bath !) no heating with gas burner beacuse hcn will soon decompse and water will be too much evoluting so yield will dramaticaly go down, sulfuric acid I HEARD the best concentration is 30 - 35%. why ? read some papers , and finnaly most important thing the pure ... hmmmmm .... over 99% , no other germans fellows can synthesis that pure chemical , the purest what i read is reduction of thiocyanate potassium (90%) , but it's a trick I HEARD when you use phosphoric acid yield will be higher, just read some paper men

Given the facts that hydrogen cyanide is a toxic gas and half of the population are unable to smell it at low concentrations making it sounds like an excellent way to win a Darwin Award!

With HCl you don't get chlorine. You'll get HCN, but it is not easily separated.

HCN dissolves in water very well and it boils at 26 C. When you heat the solution, then HCN will be driven out, but also quite some HCl (and water vapor).

If you bubble HCN through an aqueous solution of Na2CO3, then it will be absorbed and you'll end up with NaHCO3 and NaCN in solution. Don't expect any NaCN to form crystals from such a solution. The salt is highly soluble and I would expect separation of NaHCO3 to occur before any NaCN precipitates.

There are also all kinds of other issues. HCN and NaCN are very prone to aerial oxidation, leading to formation of cyanate (OCN(-)), which in turn easily hydrolyses to carbonate and ammonia. Cyanides also tend to polymerize while being partially oxidized and so-called azulmic acid is formed, which is some brown goop, which is not interesting at all.

CN(-) also is such a weak acid, that boiling down a solution of this in water (e.g. the sodium salt) will lead to great losses of HCN while NaOH remains behind. You'll end up with a mix of NaOH and NaCN at best.

I think that the best method of isolating cyanide is to use alcoholic solutions of NaOH or KOH and bubble HCN through that.

Making cyanide in a safe way is not easy at all, not even if you have the ferro- or ferricyanides at hand. From your posts I get the impression that for the near future it is best that you leave this synthesis alone and first do some other more benign chemistry. If not, then indeed Darwin's selection criterion also may be applied to your set of genes .

Some time ago i was able to produce some potassium cyanide by dry safe method from potassium ferrocyanide (yellow prussiate of potash or potassium hexacyanidoferrate(II)). Process of it's thermal decomposition is however very complex, and gives completely different results depending on decomposition conditions. I will describe them below.

Properties of K4[Fe(CN)6]. In pure state salt is white crystalline substance, commercial product is actually trihydrate K4[Fe(CN)6]*3H2O and has yellow coloration. Molar mass: 368.35 g/mol (anhydrous); 422.388 g/mol (trihydrate). Density 1.85 g/cm3 (trihydrate). Trihydrate looses water at ~70C however is not completely dehydrated below ~110C. Soluble in water: Trihydrate 28.9 g/100 mL (20 °C), insoluble in ethanol, ether. Salt decomposes without melt at temperatures above ~350-400C (depending on conditions), stable to heating at the air to about ~200C, is oxidized by oxygen at higher temperatures.

It's very remarkable that salt decomposition depends greatly on reaction conditions. Major difference depend on access of oxygen and dehydration of the salt.

Decomposition at the air.

In presence of air thermal decomposition of salt results in formation of cyanate, iron oxides and cyanogen, as well as some small quantity of cyanide. At the top layers in the crucible reactions proceeds as follows:

1. 4K4Fe(CN)6 + 3O2 => 2Fe2O3 + 16KCN + 4(CN)2
2. 2KCN + O2 => 2KOCN

Experiment shown that decomposition according to equations above proceeds above ~350C at relatively fast heating (0C => 350C in ~45 min) and above ~400C on slow heating (~2C in 1 min). Potassium cyanate is produced in molten state and blocks reaction gases to evolve freely. Some part of cyanate decomposes further forming potassium carbonate, some cyanide and carbon monoxide witch is oxydated to carbon dioxide by ferric oxide present in reaction mixture:

3. 4KOCN => K2CO3 + 2KCN + CO + N2
4. 3Fe2O3 + CO => 2Fe3O4 + CO2

Reaction mixture forms two layers, black top layer and bottom gray layer. At 450C top layer composition shows that 50% of iron still exists as K4[Fe(CN)6], while other part exists as Fe2O3, major detected compounds: KOCN, Fe2O3, KOCN. At 580C iron is exists completely in form of Fe3O4, major detected compounds: Fe3O4, K2CO3, traces (~3%) of ferrocyanide. It's remarkable that Fe3O4, K4[Fe(CN)6] and K2CO3 exist in the top black layer of the mixture, while bottom gray one shows presence of K4[Fe(CN)6], K2CO3, Fe3C and KCN. It is thought that molten paste of cyanate & iron oxides prevents lower layer from air oxydation, so lower layers contains significant amount of unreacted ferrocyanide. Summary of air reactions gives following approximate reaction equation for decomposition in presence of oxygen:

A. 6K4Fe(CN)6 + 17.5O2 => 2Fe3O4 + 22KOCN + K2CO3 + 6(CN)2 + CO2 + N2 [around ~580C].

Decomposition out of air contact.

First thing to mention here is that decomposition at closed vessel gives completely different results depending on dehydration of source compound. It's known that thermal decomposition of hydrated salt in such conditions yields CO2, NH3 and HCN, while dehydrated salt melts little above red heat with formation of iron carbide and KCN:

1. K4[Fe(CN)6] => FeC2 + 4KCN + N2

However in this case process is no also such simple, since Fe3C is also formed. To explain it's formation following reactions are assumed to exist at some extent:

2. K4Fe(CN)6 => 4KCN + Fe + N2 + 2C
3. K4Fe(CN)6 => 4KCN + Fe + (CN)2
4. 6Fe + (CN)2 = 2Fe3C + N2

At 580C this reactions take place in lower part of crucible on heating on the air and in whole mass if process is carried out of air contact. Then heated further, above 630C melting of KCN occurs, blocking free evolution of gases from reaction mixture, what can cause mixture to escape reactor crucible. Summary of decomposition reactions out of air contact gives following approximate reaction equation:

B. 6K4Fe(CN)6 => 24 KCN + 2Fe3C + 6N2 + 5C

Right way to go

Experimentation with decomposition of pure salt as shown above is not completely suitable for simple and safe method of production of pure potassium cyanide. To overcome disadvantages of pure salt decomposition some methods have been developed long ago, those are classified as dry and wet ones. Wet methods require to work with highly dangerous gaseous HCN and will not be discussed here. Dry ways are in melting of ferrocyanide in presence of alkaline compounds such as K2CO3:

1. K4[Fe(CN)6] + K2CO3 => 6KCN + FeO + CO2

But under influence of the iron oxide formed a small quantity of cyanide is transformed to cyanate, so reaction is in reality as follows:

2. K4[Fe(CN)6] + K2CO3 => 5KCN + KOCN + Fe + CO2

Combination of reaction equations above gives more accurate equation:

C. 2K4[Fe(CN)6] + 2K2CO3 => 11KCN + KOCN + FeO + Fe + 2CO2

This process is known as Leibig's brocess, and has however disadvantage sine resulting product contains cyanate and is difficult to separate from formed FeO. To overcome this disadvantages one can use more sophisticated process proposed by Wagner, witch uses additive of charcoal to reduce any cyanate formed:

D. K4[Fe(CN)6] + K2CO3 + C => 6KCN + Fe + CO2 + CO

Advantage of this process is that formed product is free from cyanate, and that metal iron is easy to separate. One more advantage is that process generates gas with reducing nature witch then formed in closed vessel forms protective atmosphere preventing cyanide from oxidation.

Experimental results.

Dehydrated ferrocyanide was prepared by tempering on the air at 150C for 2 hours. Salt was finely ground in mortar and intimately mixed with K2CO3 and lampback (taken it quantities according eq. D above) by grounding in mortal all together. This reaction mixture was placed to the porcelain crucible, covered with tightly fit porcelain lid, and was placed into electric furnace with temperature controlling program. Mixture was heated from room temperature to 560C in one hour, and is allowed to sit at this temperature for one more hour to allow free gassing of formed CO2 and CO. On completion of this period mixture is heated further to 650C in 30 minutes and allowed to sit for one hour at this temperature, this resulted in melting of reaction product and separation of iron particles. Crucible is allowed to cool to room temperature and is broken down to obtain solidified KCN/Fe mixture. Product has shiny white appearance with gray spots of iron particles evidenced by ferromagnetic properties of the sample. Product has faint bitter almond smell. All process was carried out in room without efficient ventilation or effective fume hood, no cyanogen or other smells were detected.



Method is suitable for obtaining relatively pure cyanide in safe dry way. Some details on ferrocyanide decomposition can be obtained from article attached to this message.

Attachment: Thermal Decomposition of Potassium Hexacyanoferrate (II) trihydrate.pdf (666kB)
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[Edited on 14-2-2011 by Engager]

Long time ago I performed similar experiment.
My product was hard, crystalline grey mass, smeling like bitter ... + ferromagnetic particles (however much weaker than Fe)
But this "result" gives no information about what it is.
I took a sample of this product (after purification) as catalyst for benzoin condensation.
And I had to boil mixture for very long time to obtain visible amounts of benzoin
The same amount of pure KCN gave sudden formation of benzoin after 1/10 of time needed for "pyrolytical KCN" synth.

This:
K4[Fe(CN)6] + K2CO3 + C => 6KCN + Fe + CO2 + CO
is only theory (wishful thinking).
Have you tried to do some tests for your product (carbonates, KCN content, yield) ?

I have done only qualitive test for cyanide, without quantitative analysis of the sample, however i will do this some time later in the lab, because i don't want to work with cyanogen nasties at home conditions. Images above are from "Cyanide Industry". Pyrolityc method of cyanide production is known for the long time, it surely works and was even used in industry, only thing to ensure here is that time about ~3 hours is enough to complete conversion of source products.

Here is also a description of cyanide production by Leibig's method from "The Practical Metal-Worker's Assistant", by Oliver Byrne:

This substance may be prepared by exposing ferrocyanide of potassium (yellow prussiate of potash) to a red heat in an iron crucible; then pounding the mass, and boiling it in alcohol of about spec. grav. 0.900: cyanide of potassium crystallizes on cooling the resulting solution. It is now, however, almost universally prepared for electro-metallurgical purposes, by a process which was first suggested by Messrs. F. and E. Rodgers. but afterwards more fully explained by Professor Liebig, and hence called "Liebig's Process:" it is at once both simple and easy of performance.

Ferrocyanide of potassium rounded fine, is dried over a slow fire (we have found an iron plate, or clean shovel, to serve the purpose very well): it must be constantly stirred to prevent its forming a cake upon the hot iron; when perfectly free from moisture, 8 parts must be thoroughly well mixed with three parts of carbonate of potash, also well dried: put a cast-iron crucible into the fire, and, when it is red hot, nearly fill it with the mixture, and keep up the heat by occasional augmentations of fuel: the crucible should be kept covered as much as possible. In a short time the whole fuses into a beautiful liquid with the evolution of gas. It should be kept in this state for 10 or 15 minutes, being occasionally stirred with an iron rod: the portion adhering to the red should be examined from time to time, and when the liquid on it cools white, it is an indication that it is ready to be removed from the fire; but the first time a cast-iron crucible is used, this test will not be so accurate, the salt having then a light gray color. When the crucible is removed from the fire, it should be placed upon a stone, the mass stirred, and then allowed to settle for a short time, after which the clear, or liquid part, is to be poured off into a clean iron vessel. The sediment should be scraped clean out of the crucible while it is hot, as the crucible will do to use again several times; but if the mass at bottom be allowed to cool it will be difficult to remove it from the crucible afterwards. The clear liquid poured off is cyanide of potassium, having from 25 to 30 per cent, of cyanate of potash, and other impurities generally contained in commercial yellow prussiate of potash: 80 per cent. of cyanide of potassium is the greatest proportion that this process can give. We have occasionally obtained it at 78 per cent. from commercial materials, but more generally at 70 and 72 per cent; and we have found cyanide of potassium in the market containing as little as 49 per cent. of pure cyanide.

[Edited on 15-2-2011 by Engager]

Quote: Originally posted by kmno4

Long time ago I performed similar experiment. My product was hard, crystalline grey mass, smeling like bitter ... + ferromagnetic particles (however much weaker than Fe) But this "result" gives no information about what it is. I took a sample of this product (after purification) as catalyst for benzoin condensation. And I had to boil mixture for very long time to obtain visible amounts of benzoin The same amount of pure KCN gave sudden formation of benzoin after 1/10 of time needed for "pyrolytical KCN" synth. This: K4[Fe(CN)6] + K2CO3 + C => 6KCN + Fe + CO2 + CO is only theory (wishful thinking). Have you tried to do some tests for your product (carbonates, KCN content, yield) ?

These data are not available
Just it was performed long time ago, in much simpler way than your experiment.
Synthesis via K4[Fe(CN)6] + K2CO3 + C methode is mentioned many times in books and even in this topic.
The most important to me is real amount of KCN prepared from given amount of K4[Fe(CN)6], not very nice looking equations.
If something is crystalline and sweet - it does not mean that it is pure sugar.

Quote: Originally posted by Random

What about the reaction of chloroform with amines to yield isocyanides? CHCl3 + amine + base --> isocyanide Now, if we use ammonia instead of amine? CHCl3 + NH3(g) + base --> cyanide salt?

You have to use a very strong basis eg potassium hydroxide and it is hard to keep the ammonia in solution at normal pressure.
A lot of chloride is produced as well so it is hard to fish the potassium cyanide out of the reaction mixture at the end.
Balance the equation and allow for formate etc formed by hydrolysis and you will see how disgusting it is!

Quote: Originally posted by Random

Do you know some PTC which is easy available or easy to make? I think this route is a lot easier than those other high temperature reactions.

Quote: Originally posted by Random

Also there is formamide decomposition route.

Quote: Originally posted by Nicodem

I think we should all wait our funny cyanide kewls to provide the reference for their illogical claim that alkali cyanides can be made by reacting formamide with alkali hydroxides. This patent is surely not what they had in mind (considering the required reaction conditions and all). It should not be so difficult telling us where they read about a reaction so kewl that goes against chemical theory and against experimental data confirming that formamide reacts with KOH and NaOH in the usual manner.

Quote: Originally posted by kmno4

Quote: What are exact conditions of your pyrolysis experiment? Have you added carbon to reduce cyanate? How much care was taken to protect mixture from the air? What is the temperature scheme used? These data are not available Just it was performed long time ago, in much simpler way than your experiment. Synthesis via K4[Fe(CN)6] + K2CO3 + C methode is mentioned many times in books and even in this topic. The most important to me is real amount of KCN prepared from given amount of K4[Fe(CN)6], not very nice looking equations. If something is crystalline and sweet - it does not mean that it is pure sugar.

Ok... May be this is not sugar. However, recently i made a larger batch of cyanide using method i've described. Although i haven't made precise analysis, i've observed mass loss and it was consistent with equation from the book. A batch of product was flushed with water, and filtered. Unsoluble impurities were metallic Fe and some carbon. Obtained solution was used for benzoin condensation. Procedure i've used was taken from http://www.orgsyn.org/orgsyn/prep.asp?prep=cv1p0094, refluxing period was 1 hour instead of 30 min proposed by the procedure. Benzoin was obtained with 82% yield. So purity of product remain unknown, but it is proved to be useful for benzoin condensation.


[Edited on 19-3-2011 by Engager]

Quote: Originally posted by Nicodem

Wouldn't polyethylene start "cracking" at the temperature required? Most of it might escape in form of vapors of higher olefins. If using pre-prepared tripotassium cyanurate the powder is fine enough (and chemicaly homogenous = as much as it can be) to form KOCN at lower temperatures (250-350°C).* This yields a highly homogenous and very fine product. Perhaps such product would be more ready to react with something like polyethylene at somewhat lower temperatures. Perhaps the reduction would work even better with thoroughly homogenized crude KOCN with sugar, which then carbonizes to some fine carbon that should do the job. However, at the begining there would be a lot of annoying froating due to evolved H2O and CO2 from such a "caramel candy". Starch does not melt, so perhaps it would be more apropriate even though it would be less homogenous. * This is how I once supposedly prepared some KOCN: I prepared "tripotassium cyanurate" (due to pKa3, I doubt one can prepare it stoichiometricaly pure from KOH) from cyanuric acid and 3 eq of KOH in IPA solution, vacuum filtered the white voluminous paste and while still wet (to avoid CO2 absorption) heated it on a hotplate well covered with alu-foil until up to some 250-350°C and left there for about 2h. There was some cracking of the powder at the beginning and later no more notable change. I haven't analyzed the product but given that no cyanuric acid precipitated after acidification with HCl of an aqueous solution of the product, I assume only KOCN could have formed. This was a modification based on GB710143 where Na2CO3 with cyanuric acid is used to produce NaOCN. If someone is terribly curious if this was truly KOCN, I might bother to check with IR (if someone is so kind to provide a reference spectra).

Pardon my digression concerning a parallel interest with regards to cyanuric acid possibly having other usefulness as well. I will go out on a limb here somewhat with speculation
since this seems possible but complete references are not available for having certainty about this possible scheme.

What would be more interesting for me than the IR spectra
would be an experiment to find out about the feasability of further reaction of the KOCN with additional KOH or NaOH either as a subsequent addition, or provided in excess sufficient from the beginning of the reaction, to accomplish the reaction described by Dreschel leading to the dibasic salt of cyanamide and a carbonate. This would be interesting not in regards to production of cyanides so much as it would be interesting as a path to guanidine and also to aminoguanidine.

3 KOCN + 3 KOH ------> K2CN2 + 2 K2CO3 + NH3

This is the reaction of Dreschel corrected to show the evolution of ammonia reported in the attached article, see page 11 of the pdf The Ammono Carbonic Acids Franklin, JACS 44

What I have thought about is the sum of the reactions

(HOCN)3 + 3 KOH ----> K3(OCN)3 + 3 HOH ---->

3 KOCN + 3 KOH ----> K2CN2 + 2 K2CO3 + NH3 =

--------------------------------------------------------------------

(HOCN)3 + 6 KOH ----> K2CN2 + 2 K2CO3 + NH3

Doubling the amount of hydroxide for the formation of the tripotassium cyanurate could then lead to dipotassium cyanamide. Curiosity exists whether or not this entire reaction sequence may occur in DMSO under reflux, so that byproduct H2O and NH3 is volatilized.

Subsequent treatment of the completed reaction mixture
with hydrazine sulfate could lead to aminoguanidine.
Nitrosation in situ could produce guanyl azide and cyclization to 5-aminotetrazole would seem convenient as a possible one pot synthesis.

Alternatively the completed reaction mixture might be acidified for isolation of cyanamide or cyanoguanidine
or be used as an intermediate for production of guanidine.

It remains unclear what sort of reaction condition is required for the Dreschel reaction to proceed, and with what efficiency does that described reaction occur. But the implications are certainly interesting for these other possible end products obtainable from cyanuric acid, under whatever reaction conditions, and most interesting if indeed such reactions can occur under relatively milder conditions of temperature than the pyrolytic decomposition schemes, especially if it would occur in DMSO.

Now there is a qualitative analysis approach that you know very well is more interesting than an IR spectrum

Dreschel article also attached see pae 13 of pdf

Attached also is some data about the level of hydration of
alkali cyanurates. Evidently the tripotassium cyanurate has been reported difficult. The disodium cyanurate and trisodium cyanurate reportedly crystallize in anhydrous form. So it may go equally well to work with the less expensive sodium salts.

GB710143 also attached

Attachment: The Ammono Carbonic Acids JACS.pdf (1.1MB)
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Attachment: Dreschel article.pdf (1.9MB)
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Attachment: GB710143 Cyanates from Cyanurates.pdf (791kB)
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Attachment: Alkali Cyanurates thermochemical properties JOCS 70.pdf (214kB)
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There is some additional discussion regarding the cyanate in a cyanate specific thread
http://www.sciencemadness.org/talk/viewthread.php?tid=9128

[Edited on 22-8-2011 by Rosco Bodine]

Quote: Originally posted by Rosco Bodine

Alternatively the completed reaction mixture might be acidified for isolation of cyanamide

Quote: Originally posted by Polverone

YIKES! I found the following information on another site: a patent on making metal cyanides from nitrates or nitrites and carbon; US patent 579988. KNO3 + 4C -> KCN + 3CO KNO2 + 3C -> KCN + 2CO I was unable to access the patent since I'm temporarily banned from the database for running too many queries (oops). So I decided to try just forming a pyrotechnic mixture with the right ratios. 10 grams KNO3, 4.8 of charcoal, place in stainless steel vessel and ignite with gas heating from below... As expected, the mass of what remained was much reduced, from loss of gas, solid particulates, things flung from the vessel by the reaction, etc. There was little material left in the bottom. I figured there had to be more to the method than this; after all, nobody talks about pyrotechnic formulas leaving cyanide lying around, and this is pretty much the same thing. Anyway, not having an analytical method for detecting cyanides at hand and being too stupid to look one up (and also expecting failure), I added a bit of vinegar to the residue left in the bottom. It fizzed vigorously and I caught the distinct odor of almonds... At which point I backed the heck away from there. I now intend to find a method for assaying KCN that is not so suicidal, and also to try making some more and purifying it (I have no idea what purity I obtained with this first test.) This method seems to be a vastly superior route to cyanides for the home experimenter, compared to the laborious steps given in the PMJB and the 19th century texts from which they were derived. I hope to view that patent soon and see if it contains any additional refinements (compared to crude ignition).

Quote: Originally posted by slinky

Quote: Originally posted by Polverone   YIKES! I found the following information on another site: a patent on making metal cyanides from nitrates or nitrites and carbon; US patent 579988. KNO3 + 4C -> KCN + 3CO KNO2 + 3C -> KCN + 2CO I was unable to access the patent since I'm temporarily banned from the database for running too many queries (oops). So I decided to try just forming a pyrotechnic mixture with the right ratios. 10 grams KNO3, 4.8 of charcoal, place in stainless steel vessel and ignite with gas heating from below... As expected, the mass of what remained was much reduced, from loss of gas, solid particulates, things flung from the vessel by the reaction, etc. There was little material left in the bottom. I figured there had to be more to the method than this; after all, nobody talks about pyrotechnic formulas leaving cyanide lying around, and this is pretty much the same thing. Anyway, not having an analytical method for detecting cyanides at hand and being too stupid to look one up (and also expecting failure), I added a bit of vinegar to the residue left in the bottom. It fizzed vigorously and I caught the distinct odor of almonds... At which point I backed the heck away from there. I now intend to find a method for assaying KCN that is not so suicidal, and also to try making some more and purifying it (I have no idea what purity I obtained with this first test.) This method seems to be a vastly superior route to cyanides for the home experimenter, compared to the laborious steps given in the PMJB and the 19th century texts from which they were derived. I hope to view that patent soon and see if it contains any additional refinements (compared to crude ignition). I gave this a shot. It seemed to be the most simplistic method listed in this thread. The reaction vessel I used was a small stainless steel camping pan 1/2 full with heavy duty foil over the top. The reagents occupied an approximate volume of 350 ml. The carbon was activated carbon from the pet store fish isle which I ground finely in a coffee grinder. The NaNO2 was free flowing and fine. I placed the reaction vessel over very low gas heat. Nothing happened for few mins as the mixture came up to temperature. All at once, a violent reaction happened. The foil lid blew off the small pan. It looked like a small volcano erupting. The reaction reminded me of gunpowder burning. It made a big mess. There were little black crystalline pebbles of the partially reacted mixture everywhere. A decent amount of smoke was created. It looked like there was a fire. The cleanup was painstaking because I didn't know if the reaction had succeed and there was potentially NaCN all over everything in a 5 foot radius from the cup. There was indeed a blackened crystalline fused mass in the bottom of the cup. I was so preoccupied with the mess and smoke I had made, I neglected to test the remaining product on some silver. I called it a day. I'm interested in trying this again. This time, in a much less full heavy duty stainless steel pot with a weighted lid on top to keep the spatter down. After the reaction, do you suggest that I continue heating it? Should I just allow it to cool and go from there? It seems to me that any continued heating would be irrelevant because the mixture has already literally burned on it's own. [Edited on 1.17.2012 by slinky]

Quote: Originally posted by Polverone

Oh, BTW, that patent I mentioned in the 2nd post in this thread? It involves using electrified carbon rods in molten KNO3/KNO2, so it's still not the easiest thing ever...

Quote: Originally posted by Engager

I made K4Fe(CN)6 + K2CO3 + C process for many times now and produced a lots of cyanide using this method,

Quote: Originally posted by Engager

resulting mass is black and feromagnetic this is fine too, you can separate cyanide by dissolving and filtering

Quote: Originally posted by AJKOER

The positive aspect of the thread is letting kids known that Nitrogen tri-iodide, a novelty explosive, cannot safely be prepared adding ammonia to tincture of iodine and heating the product. This could, instead, lead to a tragic poisoning by way of Hydrogen Cyanide gas fumes. So don't do it!

Quote: Originally posted by AJKOER

The reference is a bit dated but I suspect basically accurate. Source: "The Pharmaceutical journal and transactions", by Pharmaceutical Society of Great Britain on December 24, 1887, page 530:

Quote: Originally posted by entropy51

Quote: Originally posted by AJKOER   The reference is a bit dated but I suspect basically accurate. Source: "The Pharmaceutical journal and transactions", by Pharmaceutical Society of Great Britain on December 24, 1887, page 530: I suspect it is hokum. And 1887 is more than "a bit dated". You can't believe everything you read. Unless you're an arm chair chemist who doesn't own any glssware or chemicals to verify what you read.

Is it safe to buy Potassium Ferrocyanide? I mean the lab guys will ask a million questions as to why you need the compound, right? And what will you reply?

PS: I'm not interested in making this stuff. Just curious after seeing the amount of enthusiasm in here.

Quote: Originally posted by RisingSun96815

Today I replaced my thick-walled crucible with a steel soup can, and sure enough I got liquid. I let it cook for an hour, and had a black mass. So how exactly do I filter this to extract any KCN that is there?

Quote: Originally posted by madmanhere

Is it safe to buy Potassium Ferrocyanide? I mean the lab guys will ask a million questions as to why you need the compound, right? And what will you reply? PS: I'm not interested in making this stuff. Just curious after seeing the amount of enthusiasm in here.

Its so viscous! Pretty

ferro+carbonate+c method

Quote: Originally posted by Magpie

I would treat that black mass you took out of your fireplace with a lot of respect. Ie, there may be more cyanide there than you think. I suggest you test it using a Prussian Blue test as follows: 1.Place about 1 mL of water in a small test tube. 2. Add a smidgen (few mg) of FeSO4*7H20 or other soluble ferrous salt and stir until dissolved. 3. Acidify with a few drops of 1M HCl. 4. Add a smidgen of your product and stir. An intense dark blue color indicates the presence of cyanide. [Edited on 16-2-2012 by Magpie]

Finally!

Heated a pinch (may even less) of K. Ferrocyanide in a test tube. Once it became white, added excess of 88% phosphoric acid and heated the solution.

It started bubbling leaving water droplets at the side (also HCN?) and the solution turned blue suggesting the experiment was a success! The solution was not as blue as in myfanwy's experiment. Guess it's because the phosphoric acid was pure and colourless.

Sniffed the contents, but didn't get any bitter almond smell. Guess I am not genetically endowed.

Quote: Originally posted by madmanhere

Finally! Heated a pinch (may even less) of K. Ferrocyanide in a test tube. Once it became white, added excess of 88% phosphoric acid and heated the solution. It started bubbling leaving water droplets at the side (also HCN?) and the solution turned blue suggesting the experiment was a success! The solution was not as blue as in myfanwy's experiment. Guess it's because the phosphoric acid was pure and colourless. Sniffed the contents, but didn't get any bitter almond smell. Guess I am not genetically endowed.

As I said the quantity was very small. Less than a pinch of ferro. And I didn't smell when the reaction was going on- only after removing the test tube from the flame.

It was too tempting. Other than that I was doing some pretty lame stuff- like heating NaOH crystals with H3PO4 and the likes.

[Edited on 26-2-2012 by madmanhere]

Quote: Originally posted by RisingSun96815

Today I replaced my thick-walled crucible with a steel soup can, and sure enough I got liquid. I let it cook for an hour, and had a black mass. So how exactly do I filter this to extract any KCN that is there?

Quote: Originally posted by cyanureeves

i doubt you will dissolve gold with all that charcoal still absorbing all the cyanide if you succeeded. i could not get the isolated white stuff to dissolve gold only copper but after i added peroxide too. silver just disintergrated into particles.why dont you crush the stuff and filter it? [Edited on 1-3-2012 by cyanureeves]

You mean filter the way you mentioned with a precaution to prevent conversion to cyanate ?Its pretty tough to do so coz I m doing all these in my kitchen .I am thinking the 3 hour temp scheme (dont know how to establish it above a gas stove though) will melt it to liquid.Anyhow is this mass poisonous or would be harmless as ferrocyanide ?

Quote: Originally posted by madmanhere

Quote: Originally posted by cyanureeves   myfanwy did condense hcn but not with NaOH. I still don't understand how he got crystallized NaCN out of the solution. Any idea? The video shows him mixing NaOH with HCN and then the crystals without mentioning how he got it. As kotze said, one could use cold ethanol under vacuum. But I don't know how to create the vacuum.. @explnfi: Conducting the experiment in a kitchen? [Edited on 1-3-2012 by madmanhere]

Quote: Originally posted by cyanureeves

i havent tried condensing hcn. i got all the chemicals and glass and even bought two gas masks but i am really scared and havent mustered the guts yet. i think the charcoal canister russian mask will be best for this task. this summer i tried making nitric acid and all the nitric vapors leaked somewhere and never condensed.i cannot allow this to happen with hcn i got new kleck clips too. i will make nitric one more time then i will do the hcn.myfanwy did condense hcn but not with NaOH. honestly i think you need fire and a good blow dryer to get the heat up there.i believe you will get ferrocyanide if you start with ,potash and blood and iron shavings but it will stink your whole house and you need lots of heat.i used deer hooves instead of blood and did isolated the salt and did make prussian blue,i used a blue propane torch bottle i got from walmart [Edited on 1-3-2012 by cyanureeves]

Quote: Originally posted by expInfi

Quote: Originally posted by cyanureeves   i doubt you will dissolve gold with all that charcoal still absorbing all the cyanide if you succeeded. i could not get the isolated white stuff to dissolve gold only copper but after i added peroxide too. silver just disintergrated into particles.why dont you crush the stuff and filter it? [Edited on 1-3-2012 by cyanureeves] You mean filter the way you mentioned with a precaution to prevent conversion to cyanate ?Its pretty tough to do so coz I m doing all these in my kitchen .I am thinking the 3 hour temp scheme (dont know how to establish it above a gas stove though) will melt it to liquid.Anyhow is this mass poisonous or would be harmless as ferrocyanide ?

About this molten mass , do you think it is poisonous ? Or it is ferrocyanide still ? Coz I could successfully clear everything without falling dead . Just wanted to know if I was playing with a ghost without knowing

Quote: Originally posted by expInfi

Did anyone try myfanwy94 ? Condensing HCN and neutralizing with NaOH ? http://www.youtube.com/watch?v=K5NuqpdYDhE[/url]

Quote: Originally posted by RisingSun96815

Can someone tell me what specific hardware this guy used, and maybe include some links to on-line sources where they can be purchased? Also, I didn't see where NaOH came in, and the use of ethanol wasn't very detailed. Can someone go into more detail about these two processes? Thanks.

Quote: Originally posted by RisingSun96815

Quote: Originally posted by expInfi   Did anyone try myfanwy94 ? Condensing HCN and neutralizing with NaOH ? http://www.youtube.com/watch?v=K5NuqpdYDhE[/url] Can someone tell me what specific hardware this guy used, and maybe include some links to on-line sources where they can be purchased? Also, I didn't see where NaOH came in, and the use of ethanol wasn't very detailed. Can someone go into more detail about these two processes? Thanks.

Quote: Originally posted by cyanureeves

i'll be darned myfanwy did use sodium hydroxide,i was about to do it without hydroxide.well i've done it with potassium hydroxide then because i did the same except i used too much hydroxide and i also used a tube and bubbled it directly into the mix.i'm sure it had condense hcn going into the mix but myfanwy's method is better because he used phosphoric acid and i used sulfuric.of course max was smarter and had precise temp control. my nitric distillation set up consists of a rb boiling flask.arm adaptor and a alhinn condensor going into an rb flask, all in 24/40. in my case ,having pro glassware did not make me a pro because my nitric did not condense,i dont know where it went all i got was mostly sulfuric acid.i need to learn more about securing the glassware.i'm used to using coffee pots and teflon tape.you know what they say"you can take the boy out of the ghetto,but what for?"i just made that up.

Quote: Originally posted by cyanureeves

having pro glassware did not make me a pro because my nitric did not condense,i dont know where it went

Quote: Originally posted by expInfi

Could you pls answer , if vacuum is required to precipitate KCN using ethanol ?

Quote: Originally posted by entropy51

Quote: Originally posted by cyanureeves   having pro glassware did not make me a pro because my nitric did not condense,i dont know where it went Quote: Originally posted by expInfi   Could you pls answer , if vacuum is required to precipitate KCN using ethanol ? You kids are playing with fire, trying to make HCN without having a clue as to the basics of this kind of chemistry. This is what happens when you think you can learn a complicated subject by watching lame youtube videos. [Edited on 2-3-2012 by entropy51]

Quote: Originally posted by expInfi

.And pls do not judge that all are 5th grade failed.

Quote: Originally posted by entropy51

Quote: Originally posted by expInfi   .And pls do not judge that all are 5th grade failed. I see no evidence to the contrary.