the chemistry of fulminating powder?

[the freshmaker]

hi fellas!
I know this topic have been discussed before, but I hope its ok to bring this up again..? Well, I've played around with this composition for awhile, and I'm gettin' curious about this. As far as I know there isn't any proved explanation for why this mix detonates when heated/melted.
A possible explanation is that the Potassium Carbonate and the sulfur reacts to produce Potassium Polysulfide.

2 K2CO3 + S8 -> K2S + K2S4 + 2CO2 + SO2

Because Potassium Polysulfide mixed with Potassium Nitrate (1:2) also detonates when heated/melted

Like with blackpowder there isn't any single reactionscheme but the following could be posible:

4 KNO3 + K2S3 -> 3 K3SO4 + 2 N2

4 KNO3 + K2S3 -> 2 K2SO3 + K2SO4 + SO2 + 2 N2


So do any of you know if it could be posible to "produce" the produced chemical that detonates? -without first melting it together! The chemicals for this explosive mix is so easy to get, so it could be so nice, if you just could mix fx. KNO3 with another chemical to form a exposive mix wich can be detonated by flame!
Can you understand what i'm saying? I hope so! what do ya think? -seeya

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good boy with bad ideas

[Madog555]

sounds very good,

i read about this in "Improviosed Primary Explosives" it sugested melting the KNO3 and K2CO3 together but i think that it would be better to melt the K2CO3 and S together. one drawback though, it might explode.

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"To live is to suffer, to survive... well thats to find meaning into suffering." -DMX

[rikkitikkitavi]

I have read the same text and found it fascinating that such simple mixture could be so powerful as claimed.
But the reason for it to be melted together could be that the chemicals are get very very well mixed, almost at molecular level, something that cant be done easily with blackpowder. Hence a much higher combustionrate.
So maybe just mixing them together is not enough.

Couldnt you use KOH aswell as K2CO3 to make K2S4 ?

KOH is a stronger base than K2CO3 and the
S(2-) ion is a very strong base(stronger than OH- in water solution atleast)

Could it really detonate?

BTW , why would a paint shop sell sulfur ?
Atleast here in sweden some do, and since now I am proud owner of 1.5 kg sulfur flour. The guys in the shop had no idea why they stocked it, but only lifted an eyebrow when I said I was going to use it for black powder guns

I will get back when I tried it.

/rickard

[This message has been edited by rikkitikkitavi (edited December 22, 2001).]

[This message has been edited by rikkitikkitavi (edited December 22, 2001).]

[Madog555]

i know, but maybe if u melt the S and Potassium Carbonate together it will make Potassium Polysulfide. i think this would work

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"To live is to suffer, to survive... well thats to find meaning into suffering." -DMX

[nbk2000]

The fusion mix may be absorbing nitrogen from the air also.

Just like when a mix of carbonate and carbon are fused, it absorbes nitrogen to form a cyanide (CN), so too may the mix of carbonate and sulfur form ? (SN).

And nitrogen-sulfur bonds are weak.

Just my theory.

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"I have begun evil, I shall end evil. That is the end that awaits me."

Go here (http://briefcase.yahoo.com/nbk2k) to download the NBK2000 files and videos.

[Jumala]

Has anyone tryed the receipe in the following text. ( I think it is the original receipe)
I have ordered some potash but I havn´t got it until now.

** This is fulminating powder***, made, according to Ure's "Dictionary of Chemistry," first American edition, Philadelphia, 1821 by triturating in a warm mortar, three parts by weight of nitre, two of carbonate of potash, and one of flowers of sulfur. Its effects, when fused in a ladle, and then set on fire, are very great. The whole of the melted fluid explodes with an intolerable noise, and the ladle is commonly disfigured, as if it had received a strong blow downwards.
*** Samuel Guthrie, Jr. (ef. Archeion, 13, 11 ff. [19311), manufactured and sold in this country large quantities of a similar material. In a letter to Benjamin Silliman dated September 12, 1831 (Am. J. Sci. Arts, 21, 288 ff. [18321), he says:
I send you two small phials of nitrated sulphuret of potash, or yellow powder, as it is usually called in this country.... I have made some hundred pounds of it, which were eagerly bought up by hunters and sportsmen for priming fire arms, a purpose which it answered most admirably; and, but for the happy introduction of powder for priming, which is ignited by percussion, it would long since have gone into extensive use.
With this preparation I have had much to do, and I doubt whether, irf the whole circle of experimental philosophy, many cases can be found involving dangers more appalling, or more difficult to be overcome, than melting fulminating powder and saving the product, and reducing the process to a business operation. I have had with it some eight or ten tremendous explosions, and in one of them I received, full in my face and eyes, the flame of a quarter of a pound of the composition, just as it had become thoroughly melted.
The common proportions of 3 parts of nitre, 2 parts of carbonate of potash and 1 part of sulphur, gave a powder three times quicker than common black powder; but, by melting together 2 parts of nitre and 1 of carbonate of potash, and when the mass was cold adding to 41/2 parts of it, 1 part of sulphyr equal in the 100, to 54.54 dry nitre, 27.27 dry carbonate of potash and 18.19 sulphtir-a greatly superior composition was produced, burning no less than eight and one half times quicker than the best common powder. The substances were intimately ground together, and then melted to a waxy consistence, upon an iron plate of one inch in thickness, heated over a mtiffled furnace, taking care to knead the mass assiduously, and remove the plate as often as the bottom of the mass became pretty slippery.
By the previously melting together of the nitre and carbonate of potash, a more intimate union of these substances was effected than could possibly be made by mechanical means,. or by the slight melting which was admissible in the after process; and by the slight melting of the whole upon a thick iron plate, I was able to conduct the business with facility and safety. The melted mass, after being cold, is as hard and porous as pumice stone, and is grained with di,-neulty; but there is a stage when it is cooling in which it is verv crumbly, and it should then be powdered upon a board, with a small wooden cylinder, and put up hot, without sorting the grains or even sifting out the flour.

[Madog555]

the second one is the one i was talkin about, you can find it at the bottom of improvised Primary explosives

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"To live is to suffer, to survive... well thats to find meaning into suffering." -DMX

[vulture]

Jumala, how is fulminating powder called in german?

[Jumala]

Sorry, I have no idea. I have found only the text posted before.

Is it possible that it has no special german name like most other powder mixtures too.

[Rhadon]

Yes, I think Jumala's right. Fulminates (when referring to mercury fulminate and compounds similar to this) are called "Fulminate", but I couldn't find a translation for "fulminating powder"

Rhadon

[FadeToBlackened]

In "Improvised Primary Explosives" There is a little bit about this, The fulminates (CNO), Fulminating compounds (usually nitrides) and fulminating powder. Fulminate actually means something like, erupting with violence, or screaming, or something like that. So Fulminating Powder, simply means exploding powder

[Mr Cool]

Yeah, fulminans is a latin word, meaning angry or something like that. It's been a while since I did latin at school, but it means something like that.
Potassium polysulphide can be bought as a metal ageing chemical, for example from <a href="http://www.rose-chemicals.co.uk/patinati.htm" target="_blank">www.rose-chemicals.co.uk/patinati.htm</a> £16/100g, so if you want to do some experimenting it might be worth buying it pure.

[Rhadon]

My chemistry lexicon says that "fulminate" is derived from "fulmen" what means lightning.

[vulture]

Did any of you ever tried making fulminating powder with AN instead of KNO3?

[the freshmaker]

yea I have tried using AN instead! It doesn't work!The AN just decomposed/melted with no explosive reaction at all.. Though I've tried to add a little Aluminium and that gives a little more powerfull explosion and a small flash! -try it!
Maybe other Nitrates with a melting point around the m.p of KNO3 would work..?

[ January 07, 2002: Message edited by: the freshmaker ]</p>

[mr.evil]

i've molted K2CO3+KNO3 together, an brown-grey substance was formed, when dry and grinded down, i put the S8 to it. It doesn't burn/Detonate:(

this afternoon i try to melt S8+K2CO3 together. Hopefully this will work :confused:

Cya

[Alchemist]

Hello all,

At one time K or Na polysulfide used to be called Liver of Sulfur do to it's color! I have made this by melting togeather equal amounts of sulfur and DRY Potassium Carbonate. It works very well in the fulminating powder composition. It may be worth while trying different ratio's of Sulfur and Potassium Carbonate and maybe even different Sulfides or even Sulfites! Who knows. Looks like a lot of experimenting to be done here. Also what about trying Nitrite or dare I say it even Chlorate instead of Nitrate.

Have fun then!

[vulture]

I looked it up, melting the potassiumcarbonate and sulfur together yields potassium polysulfide which you need for the fulminating powder. Add the KNO3 afterwards.

[kingspaz]

could the potassium polysulphide be made, powdered afterwards and then mixed with KNO3 making a useful composition? heat from a flame would melt it = boom!...i've probably made some mistakes here...havne't read the whole thread!

[Pu239 Stuchtiger]

There still seems to be a lot of confusion (extreme confusion guaranteed for newbies); I'll attempt to make a post that will be more clear.

The typical "fulminating powder" is a mix of a polysulfide, typically sodium or potassium polysulfide: Na2Sx, K2Sx; and an oxidizer. The oxidizer used is usually a metallic nitrate, considering that K2Sx is such a powerful reducer that more powerful oxidizers would be extremely dangerous. So, the typical "fulminating powder" simply is a reducer / oxidizer mixture.

The several main types of alkaline polysulfides are as follows (I'll use the symbol "Am" for "alkaline metal"): Am2S2, Am2S3, Am2S4, Am2S5, Am2S6. All polysulfides are water soluble. Polysulfides react violently with oxidizers, such as hydrogen peroxide. Try droppering 30% H2O2 onto a small pile of Am2Sx; the result is a small explosion (do this with appropriate safety gear only, this reaction forms lye, which obviously is sprayed everywhere). The polysulfides range from yellow to a deep orange. The higher the value of the "x" in Am2Sx, the deeper the color. It is simple to prepare each kind of polysulfide; simply adjust the amount of sulfur used.

I don't recommend producing alkaline polysulfides by heating an aqueous solution of Am2CO3 or AmHCO3 or AmOH; this produces Am2Sx, but also a huge amount of Am2SO3 and AmHSO3. Right now, I recommend producing it by heating the sulfur and the alkaline compound (basic pH for that compound, of course). Another (FAR superior) method is currently under development.

Be cautious when preparing a polysulfide with NaOH; it produces large amounts of hydrogen sulfide, a gas more toxic than even hydrogen cyanide.

2NaOH + S8 --> Na2S6 + H2S + SO2

<small>[ April 17, 2002, 11:20 PM: Message edited by: Pu239 Stuchtiger ]</small>

[plasma]

To make production of polysulfides from hydroxides more safe one could lead the H2S into a solution with free metal ions. The H2S would then react with the metal ions and create a sulfide. Like this :

2NaCl(s) + (water) -> 2Na+ 2Cl-

H2S(g) + 2NaCl(aq) -> Na2S + 2HCl

The very poisonus H2S is then avoided. MUCH safer but still dangerous, gas leaks do occur.

[vulture]

Your reaction will not work with NaCl, because H2S is a weaker acid than HCl (weaker acids never set free stronger acids unless the other acid is more volatile). It will work with NaOH + H2S though.

[plasma]

Ohh... Didn't think of that. :)

[xyz]

Because the mix detonates when heated/melted (instead of simply deflagrating like BP), would it be possible to make it without having to grind the ingredients up like you do with BP? e.g. melting together the ingredients at a temp low enough not to cause detonation instead of grinding them up and then mixing

How wide is the margin between hot enough to melt and hot enough to detonate? If you can simply melt it then it will save a lot of ball milling

[Pu239 Stuchtiger]

Dissolve the Na2Sx and the NaNO3 (or K, whatever) in water, mix the two, and recrystalize. DO NOT melt the mix of the two.

[xyz]

Ok, so recrystallizing will work instead of grinding. Will this work with any comp where both the fuel and the oxidiser are soluble in water? e.g. KNO3 and Sugar

[Polverone]

In general, you can't substitute crystallization for fusion (melting). This goes for the fulminating powder as well. The polysulfides are quite hygroscopic, so you would have a hard time getting the fulminating powder to work this way also. In the case of sugar/saltpeter, I can tell you that I've many times made KNO3/sucrose solutions and dried them. They don't burn nearly as fast as ballmilled KNO3/sucrose, much less a composition that's been ballmilled and then fused together. But the fusion is hazardous, so you'd be better off getting some sorbitol (lower melting point) if you want to make rocket motors. If you're making smoke bombs, pretty much any old way of combining the KNO3/sucrose will do.

[vulture]

Doesn't the polysulfide decompose into NaOH and H2S in contact with water?

[Polverone]

I have discovered, from reviewing several articles, that polysulfides can form in aqueous media but that they are easily oxidized by exposure to air. They form thiosulfate when oxidized.

Does anyone have access to Chymia vol. 2, 1954? It contains an article by Tenney L. Davis called "Pulvis Fulminans" that explores fulminating powder in depth and apparently gives an improved formulation for it.