Sciencemadness Discussion Board

Melting whistle mix

Dornier 335A - 2-3-2014 at 12:26

I have discovered something interesting about one particular whistle mix composition. Potassium chlorate and sodium benzoate in a 75 to 25 ratio by weight has surprisingly high ignition temperature (approximately 400°C) and starts to melt much earlier, at around 310°C.

In this molten state, the whistle mix turns out to be a powerful primary explosive. It detonates violently when confined in just a few layers of aluminium foil, turning the foil into fine powder. Small amounts detonated against thin aluminium plates showed that it is superior to both silver acetylide double salt and nano-Armstrong's mixture. This is 4 mg detonated against a 0.11 mm thick aluminium plate (hole is 16 mm in diameter):


After that I detonated 30 mg of the molten mix on an aluminium can to compare it to the same amount of ETN.
Here are the results:
Whistle mix:

ETN:


As you can see, the liquid whistle mix displays extraordinary brisance. The solid powder mix doesn't behave like this at all, so it's obvious that the homogeneity and lower activation energy of the liquid is the key here. I guess the molten mixture behaves almost like an organic chlorate. I'm thinking about Blaster's old thread about ethyl perchlorate. He showed its extreme brisance, and it would certainly explain my results if the whistle mix is acting in a similar fashion.

papaya - 2-3-2014 at 13:24

Very interesting, unfortunately there's no safe way to prepare such a mixture in more than few mg scale, or ? Anyway, must serve a good demonstration!

Nice channel btw!

[Edited on 2-3-2014 by papaya]

Zyklon-A - 2-3-2014 at 13:54

Have you seen this?

[Edited on 2-3-2014 by Zyklonb]

Rosco Bodine - 2-3-2014 at 16:23

Fulminating mixtures exist and evidently this is another one. There are obscure mentions of a few such mixtures in mostly the old literature. Here is another one reported in a thread where some others are discussed.
http://www.sciencemadness.org/talk/viewthread.php?tid=13283&...

That is the only reference I ever saw to the mixture of potassium ferricyanide with ammonium nitrate being a fulminating mixture and I never tested it by experiment.
But it would suggest that possibly the same could occur with ammonium perchlorate. There are likely a few of these type mixture that can DDT and it is the ones that do it in small quantity that are most interesting.

[Edited on 3-3-2014 by Rosco Bodine]

Bert - 2-3-2014 at 17:31

All of the whistle mixes made with Chlorate are a bit too touchy for use in a modern factory setting- And if compacted, some are cap sensitive HE's. The idea of MELTING those mixes makes my hair stand up. Interesting performance, wouldn't want to depend on it.

Varmint - 2-3-2014 at 18:48

Obvious next step is to allow it to cool and solidify, then attempt ignition (perhaps detonation?) with fuse or a tiny purpose-built squib.

DAS

Bert - 2-3-2014 at 21:31

KClO3: MP 356 C decomposes 400 C

Ba(ClO3)2: MP 414 C decomposes ?

NaClO3: MP 248 C decomposes 250 C (let's not try that one...)

Sodium benzoate: MP 300 C decomposes 450 C, auto ignition 500 C

Sodium salycilate: MP 200 C decomposes (?) C, auto ignition 337 C

Potassium Hydrogen Terephthalate: MP 295 C, auto ignition (?)

Potassium benzoate: MP ~123 C, auto ignition >950 C (Oooh, I think we have a candidate!)

Potassium salicylate: MP ? auto ignition ?

Copper benzoate: MP ? auto ignition ?

Gallic acid: MP 250 C auto ignition ?

Potassium 2, 4 dinitrophenolate: eh, let's not!


So, I'm going to dig out some Barium chlorate and Potassium benzoate... Just because.


[Edited on 3-3-2014 by Bert]

[Edited on 3-3-2014 by Bert]

Dornier 335A - 3-3-2014 at 05:22

I have melted small amounts and let it solidify as small flakes. These burn really quickly and fly away like rockets. I haven't attempted to detonate them but I could try tomorrow.

Rosco, ammonium nitrate and potassium ferricyanide is certainly not a fulminating mixture. Potassium chlorate and ferricyanide is a good one but it lacks brisance. I have a video about it here.

Here is another video with some small scale whistle mix tests.

Bert, why barium chlorate instead of potassium chlorate? To get a higher ignition point?
Why not potassium dinitrophenolate and sodium chlorate?

Praxichys - 3-3-2014 at 06:30

What's with the term fulminating mixture?

The fulminate anion is -CNO, which this is clearly not. If anything, it's an archaic term for an "explosive mixture" or a "detonating mixture." You wouldn't say sal ammoniac or oil of vitriol, so what's with fulminating? This isn't the seventeenth century.

Besides, it's confusing. In the thread Rosco referenced earlier, which contains patents from as early as 1901, the term "fulminate" is used 85 times and exclusively for metal salts of -CNO. It has been a dead term for "explosive" for at least a hundred years.

DubaiAmateurRocketry - 3-3-2014 at 08:25

Nice!

Why are you grinding potassium chlorate and sodium benzoate ? They both are sparkling soluble in hot water.
KClO3.
57 g/100 mL (100 °C)
Sodium benzoate
62.9 g/100ml (rt)
You can try adding them to boiling water until it stops dissolving more. Then chill the solution. You should end up having them mixed to a new level than nano. Then melt it and ignite, and tell me what happens! It should be a good primary hehe. You can publish some work on your nano flash powder.

Quote: Originally posted by Zyklonb  
Have you seen this?


Dornier's flash powder etc is on another level.


[Edited on 3-3-2014 by DubaiAmateurRocketry]

Dornier 335A - 3-3-2014 at 10:36

That would not work very well for two reasons. First, sodium benzoate is way to soluble to precipitate fully when the solution is cooled. Secondly, I don't think they would mix at all. Wouldn't the two salts just crystallize into large separate crystals when the solution is cooled down? A better approach is to pour the warm solution into cold ethanol.

DubaiAmateurRocketry - 3-3-2014 at 11:02

Ah yes, potassium chlorate might precepitate out first as the problem, true. Ethanol idea would be good, acetone probably too.

Rosco Bodine - 3-3-2014 at 13:02

Quote: Originally posted by Praxichys  
What's with the term fulminating mixture?


What is with the term is the correct use of language.

Quote:

The fulminate anion is -CNO, which this is clearly not. If anything, it's an archaic term for an "explosive mixture" or a "detonating mixture." You wouldn't say sal ammoniac or oil of vitriol, so what's with fulminating? This isn't the seventeenth century.


No it is not an archaic term for just any explosive mixture, but a particular type of behavior about an explosive mixture
which progresses rapidly from burning to detonation.

Quote:

Besides, it's confusing. In the thread Rosco referenced earlier, which contains patents from as early as 1901, the term "fulminate" is used 85 times and exclusively for metal salts of -CNO. It has been a dead term for "explosive" for at least a hundred years.


Knowledge can be confusing, and can even cause a headache. You have my sympathy.

Fulminating never was used just exclsuively as a term for "explosive" but is a more general term that could even apply to a strident tirade of criticism as a verbal communication could be called "fulminating" when the point made severely as a deserved criticism lands home with a "kaboom" of understanding. The root word I think is latin fulmen or fulminis meaning generally thunder, and the word origin is lost in antiquity.

http://www.latin-dictionary.net/definition/21133/fulmen-fulm...

I did not use the term "fulminate" as applies to the isomer of cyanate described by Liebig, but I used the term "fulminating mixture" two words as a phrase neither of which words is fulminate. There are other correct usage applications for the word fulminating to decribe the explosive nature of other explosive compounds and mixtures than applies exclusively to the salt of fulminic acid. Fulminating gold is an example, as is fulminating silver, neither of which are salts of fulminic acid. For example fulminating silver a distinctly different compound from silver fulminate. Archaic perhaps, but still correct usage so far as I know. Consult your philosophers' stone regarding this matter and get back to me :P

Rosco Bodine - 3-3-2014 at 13:26

Quote: Originally posted by Dornier 335A  


Rosco, ammonium nitrate and potassium ferricyanide is certainly not a fulminating mixture. Potassium chlorate and ferricyanide is a good one but it lacks brisance. I have a video about it here.


I said I haven't tested the mixture reported in the 1891 text.
Have you?

I already knew about the mixture you show in your video, actually knew about it 50 years ago but never experimented with it extensively. There are several different compounds and/or mixture compositions that will DDT to a low order detonation lacking brisance when unconfined but above a certain quantity and/or with confinement become brisant when having made the transition to high order detonation. The quantities and conditions vary widely for what is required to enable that transition.

Bert - 3-3-2014 at 14:03

Anyone seen numbers on (anhydrous) low melting point/eutectic mixtures of Sodium and/or Potassium chlorate and other oxidizers? Ones having MP's substantially below the decomposition temperatures of the chlorate(s)?

Enquiring minds want to know!

[Edited on 4-3-2014 by Bert]

Dornier 335A - 3-3-2014 at 15:04

Quote: Originally posted by Rosco Bodine  

I said I haven't tested the mixture reported in the 1891 text.
Have you?

I already knew about the mixture you show in your video, actually knew about it 50 years ago but never experimented with it extensively. There are several different compounds and/or mixture compositions that will DDT to a low order detonation lacking brisance when unconfined but above a certain quantity and/or with confinement become brisant when having made the transition to high order detonation. The quantities and conditions vary widely for what is required to enable that transition.

I tested that mixture a while ago. I couldn't get it go ignite, only melt and decompose. With some added magnesium powder, I got a delayed flash powder. After ignition, it hissed slightly and went poof after a fraction of a second.

K3Fe(CN)6 / KClO3 is one of the more widely known detonating mixtures. When the powders are as homogeneously mixed as what I showed in my video, 10 mg is enough to self-confine. But it still won't dent an aluminium plate more than slightly even when confined. Yellow powder behaves similarly for me. I suppose the amounts I have tested could be too small, but at least for other primaries, self-confinement means that detonation is very close.

Rosco Bodine - 3-3-2014 at 15:58

Mixtures are not as predictable as compounds, but there can be some things done as experiments. For example see what effect is had by using dextrine to binder the composition into a pellet, working upwards to even a hundred milligrams, or more. Some materials which absolutely will DDT eventually at a certain weight and geometry and confinement combination, have a minimum amount requirement for DDT that is inconveniently large, which prevents use of such materials due to lack of economy and for the inconvenient larger scale of the device that would use such materials. A possibly useful test is to granulate the powder mixture dampened with a binder and press the dried granules and see what its response to initiation by lead azide. If it has an ability to detonate that should reveal the ability. But it is expected to be limited by minimums for critical diameter and critical mass just like applies to a compound. WRT the ferricyanide and ammonium nitrate, since no conditions or examples are given, it is difficult to rule out or dismiss the information as an error based on a spot test where the small quantity may not develop the described detonation, but it could well be an error in the literature. It wouldn't be the first or last example of a mistake if that turns out to be the case.

[Edited on 4-3-2014 by Rosco Bodine]

papaya - 6-3-2014 at 10:12

Now try with benzoic acid instead of benzoate - you'll be surprized how difficult is it to ignite (I think due to sublimation) even confined (some 20mg) didn't do anything, however a hammer blow gives a sharp crack.

PHILOU Zrealone - 7-3-2014 at 04:31

Maybe when melting the mix of KClO3/NaO2C-C6H5 turns into a more sensitive mix of KClO3/NaO2C-C6H5/NaClO3/KO2C-C6H5 with a lower Ea due to NaClO3. In the molten state, the average number of molecules with a sufficient energy to ensure propagation of the reaction is much higher and you spare energy from the fusion enthalpy...so the propagation of the burning flame front/deflagration-detonation wave is much faster.

Should be good to test KClO3/KO2C-C6H5 and NaClO3/NaO2C-C6H5 and NaClO3/KO2C-C6H5 as comparison

A real sand crushing test, lead block test and VOD determination should be done.
Sand crushing test can also be used to determine the detonation ability (critical mass).

Last but not least maybe try some 3,5-dinitrobenzoate and dinitrophenates. They already display VOD above 6000 m/s so the whistle mix made from those would be more on the primary side.

Dornier 335A - 7-3-2014 at 10:00

Update:
I detonated 0.10 g of the liquid mixture on a 0.5 mm thick steel plate with great results!


I will try with NaClO3 soon. Is there any good way to prepare potassium benzoate? It's solubility is very similar to that of sodium benzoate which makes it a bit problematic.

Zyklon-A - 7-3-2014 at 10:12


Quote:
One very common way to make potassium benzoate is by oxidizing toluene.[4]

Another way to synthesize potassium benzoate in the lab setting is by reacting methyl benzoate with potassium thioacetate.[

[4]

You probably already saw this, but it may help.

DubaiAmateurRocketry - 7-3-2014 at 10:39

That is some impressive result! Does it behave similar if you ignite it without melting?

It would make a good primary, but the thing that this need melting is a problem. However might be overcomed on a re-design of a special detonator for this.

PHILOU Zrealone - 7-3-2014 at 10:59

Quote: Originally posted by Dornier 335A  
Update:
I will try with NaClO3 soon. Is there any good way to prepare potassium benzoate? It's solubility is very similar to that of sodium benzoate which makes it a bit problematic.

Very common organic chemistry ;-)
Take sodium benzoate, acidify it with concentrated mineral acid...benzoic acid will be relatively unsoluble in the water and cristallize/precipitate/flocculates.
Filter it off and allow it to react with K2CO3, KHCO3 or KOH.

PHILOU Zrealone - 7-3-2014 at 12:04

Quote: Originally posted by Dornier 335A  
Update:
I will try with NaClO3 soon. Is there any good way to prepare potassium benzoate? It's solubility is very similar to that of sodium benzoate which makes it a bit problematic.

Very common organic chemistry ;-)
Take sodium benzoate, acidify it with concentrated mineral acid...benzoic acid will be relatively unsoluble in the water and cristallize/precipitate/flocculates.
Filter it off and allow it to react with K2CO3, KHCO3 or KOH.

Dornier 335A - 8-3-2014 at 07:37

I came to the same conclusion shortly after posting but thank you anyway PHILOU Zrealone.

Update 2:
The same person who made the 30 mg ETN test performed another, this time identical to my 0.5 mm steel plate test. The results were very similar: 5.5 mm deep dent (whistle mix) vs. 6 mm for ETN, and the maximum angles of the dents were 135° and 130° respectively.

Something of more importance is that the melted, solidified and then crushed mixture can go high order with very little confinement. 10 mg ignited by a tiny amount of KClO3 and K3[Fe(CN)6] in just a few layers of aluminium foil exploded with a sharp bang. This might actually have some potential as primary if the sensitivity isn't exceedingly high.

papaya - 8-3-2014 at 11:49

Dornier, don't you want to try the same with KClO4 instead of KClO3, maybe even more powerful?

Dornier 335A - 8-3-2014 at 13:09

I would, but I don't own any perchlorates at all. I also doubt it would be more powerful, as its melting point is higher than most fuels' autoignition temperatures. Anyone here who is able to test this with KClO4?

DubaiAmateurRocketry - 9-3-2014 at 01:41

I have some perchloate. However I dont own any benzoate. Have you tried nano hexamine mixtures? problem is that they dont melt, however I can try dissolving hexamine and ammonium perchlorate in water and recrystallizing them, it should be very well mixed then. Potassium perchlorate is too insoluable, sodium and lithium perchlorate forms hydrates.

Dornier 335A - 9-3-2014 at 07:06

Do you have any fuel normally used in whistle mixtures? Hexamine will not work here, it should be an aromatic salt.

Bert, I tried copper benzoate with KClO3 in a 20/80 ratio by weight. It's a beautiful light blue mixture, which deflagrates quickly with a blueish flame. It ignites before melting, but strong heating and confinement caused detonation.


Have you tested Ba(ClO3)2 and potassium benzoate yet?

EDIT:
I pressed the remaining 0.1 g in a thin walled aluminium foil tube, again with a few mg KClO3/K3[Fe(CN)6] as primer. It went of with an amazingly loud and sharp bang and shattered the aluminium plate it was placed on. So yet another mixture with potential as primary.

[Edited on 9-3-2014 by Dornier 335A]

Bert - 9-3-2014 at 07:10

Outside of high pressure (rocket engine) use, NH3ClO4 often isn't the oxidizer of choice for speed.

NH3ClO4 fireworks star mixtures are generally harder to ignite, slower burning and have lower critical speeds than similar mixes made with KClO4.

For uses where the solid reaction products left by KClO4 detract from flame color & transparency, NH3ClO4 is often substitutes- But almost always with a few % of the Potassium salt to enhance ignition and burn speed.

KClO4 and hexamine mixture burns slowly compared to benzoate or salicylate fuels. We sometimes substitute a few % hexamine for other hot, fast burning fuels in fireworks star mixes to slow & cool the burn, as in blue mixes that would turn to green at too high temperatures.

Usually if you melt the perchlorate in a mix, the stuff is on fire...

(edit)
No, I have not yet tried to melt any whistle fuel analogues. Kind of busy with the work that pays the bills-

[Edited on 9-3-2014 by Bert]

PHILOU Zrealone - 10-3-2014 at 01:38

The use of aromatic salts compounds is needed:
-1°) to make the salt resist the heating without sublimation or volatilisation
-2°) because of the high % of charing when heated so the mix is a kind of chlorate/C mix (with atomic or molecular C).
-3°) the oxydation/burning set free some organic acids that participates to the unstability of the chlorate and lower the activation energy during the combustion process.

For this reasons also reaction with perchlorates or with hexamine will behave very differently and not go D2D in tiny amounts.

Maybe hexamine salt and chlorate will provide a different result, but this is another story because in the mix you would have an acidic moeity (hexamine salts are mildly acidic) and so some HClO3 would form and fix to the hexamine to make hexamine di-chlorate salt... Most organic amine chlorate salts are sensitive HE (choc, friction and heat) even more than the perchlorate ones. So this would be like a gun-powder composition with a detonating stuff dispersed into it (between detonation and deflagration).

Edit:
-Copper doesn't stand well chlorate...I had some CuCl2 and CuOCl used to get some green shade decomposing into NaClO3 composition there was a Cl2 smell.

-For the stupid ones don't forget the rule no ammonium salt mixed with chlorates...so no ammonium benzoate mixing with KClO3 or NaClO3! Spontaneous ignition might occure at any time.

[Edited on 10-3-2014 by PHILOU Zrealone]

packetforger - 10-3-2014 at 08:55

As P. Zrealone mentions, the use of copper salts mixed with chlorates is in general a bad idea, copper contamination of chlorates is generally percieved as a pretty awful safety risk... Cannot imagine doing it deliberately! It is probably for this reason - copper sensitizes chlorate quite a bit, and the benzoate is easily enough going to act as a fuel...

As Bert mentioned, Ammonium Perchlorate is a not-so-great oxidizer for use in stuff outside of rocket propellants as it is fairly slow stuff. it would actually be interesting though to test Ammonium Perchlorate recrystallized with hexamine as a rocket propellant though, I imagine said mix would evolve a fair amount of gas and be a decent propellant, though it would likely need a bit of aluminium added to get it going fast enough to get stuff off the ground. Using a deep core would be advised as opposed to an end-burning design.

These mixtures, while interesting, do not strike me as particularly suitable as replacements for primaries, mostly because all of them seem to suffer some inherent instability (f.ex: copper and chlorate...). The chlorate and sodium benzoate mix does look interesting though, I would love to give it a shot sometime if it seems to be able to self confine in such small amounts. Melting a small quantity of it onto a bridgewire might make a decent electrically fired squib.

Dornier 335A - 7-6-2014 at 05:28

I ran a series of tests with sodium chlorate and sodium benzoate. At first the mixture seemed to behave identically with the potassium chlorate version, with the exception that now the chlorate melted before the benzoate.
What became apparent after a few tests was that the mixture was more difficult to detonate properly than with KClO3. It did not always go high order when confined in aluminium foil and heated. The aluminium fragments were also larger which indicates less brisance. I had expected the opposite. The somewhat disappointing results are likely due to the melting point and decomposition point of NaClO3 not being matched very well by those of the fuel.

markx - 9-6-2014 at 05:22

Perhaps this mixture offers a more convenient and reliable way of thermal initiation without the undue sensitivity that plagues most primaries. Although the fact that it needs a rather controlled gradual heating to first melt and then detonate, will most probably complicate things. A bulky metal or perhaps a ceramic interface that transfers the heat gradually from a pyrotechnical mixture to the KClO3-bezoate charge might work in this case, but it will not be convenient and tends to become bulky, cumbersome and unpredictably delayed as most thermo-shock based initiators. Though as a proof of concept test, it might be worth investigating....

PHILOU Zrealone - 13-6-2014 at 09:56

Quote: Originally posted by Dornier 335A  
I ran a series of tests with sodium chlorate and sodium benzoate. At first the mixture seemed to behave identically with the potassium chlorate version, with the exception that now the chlorate melted before the benzoate.
What became apparent after a few tests was that the mixture was more difficult to detonate properly than with KClO3. It did not always go high order when confined in aluminium foil and heated. The aluminium fragments were also larger which indicates less brisance. I had expected the opposite. The somewhat disappointing results are likely due to the melting point and decomposition point of NaClO3 not being matched very well by those of the fuel.

Maybe NaClO3 cristallises with water or catch water from the air more than KClO3 does...are you sure the NaClO3 was anhydrous and kept away from moist air?

franklyn - 13-6-2014 at 18:37

Hello everyone, been absent here awhile. This topic sparks my interest. As PHILOU Zrealone and Dornier 335A concur, double replacement is forming a double salt. Co-crystallized salts containing oxidizer and fuel , ordinarily tend to be sensitive. Chlorate with organic fuel always react to some extent. What is really remarkable is that this mixture is able to melt without immediately exploding , has high explosion temperature and high impact insensitivity. The expected properties of the resultant double salt will exhibit more susceptibility to shock given the intimate composition of anions, as Dornier 335A has already observed www.sciencemadness.org/talk/viewthread.php?tid=29259#pid3218...

Elsewhere I had proposed :

" Tricyanomethane and Trinitromethane form ionic metal salts. A way in which the two
moieties might be compounded is by a solution of equal parts of Magnesium Tricyano -
methanide and Magnesium Trinitromethanide co-crystallized as a double salt , thus
Mg{C(CN)3}2 + Mg{C(NO2)3}2 => 2 Mg{C(CN)3C(NO2)3} => 2 MgO + 10 CO + 6 N2

In the same way , Benzoate and Chlorate salts , both of either Calcium or Magnesium should result in a double salt. Of course this would be a compound with a one Chlorate anion per Benzoate anion. Performance would be much reduced. A melt of Benzoate in excess Chlorate , of course yields better oxygen balance. The wavering quality of the product produced must be attributable to inconsistent inhomogeneous crystallization. www.sciencemadness.org/talk/viewthread.php?tid=29259&pag...
A way to obtain a well uniform product is to first obtain the stoichiometric double salt and then subsequently to blend that in with a greater amount of Chlorate salt.

__________________________________________


First we obtain the stoichiometric Calcium Benzoate Chlorate double salt

Ca(C7H5O2)2 + Ca(ClO3)2 => Ca2(C7H5O2)2(ClO3)2
Having a molar weight ratio of 282 : 207

Next we compound this with Sodium Chlorate

Ca2(C7H5O2)2(ClO3)2 + 3 Na(ClO3)
Having a molar weight ratio of 489 : 320

which will detonate into
=> CaO + CaCl2 + 3 NaCl + 14 CO + 4 H2O + H2


.

[Edited on 14-6-2014 by franklyn]

franklyn - 14-6-2014 at 20:51

The question of what are the optimal ratios of Benzoate to Chlorate confirms that zero oxygen balance yields the highest heat value per weight of material.
Ignoring everything to the left of NaCl in the balanced equations seen below , and just summing the heat of formation of CO2 , CO , and H2O , in ratio to the total weight of the ingredients , the higher the number , the higher the heat value , an additional 192 kilocal for every mol of NaClO3.

This does not automatically confer higher brisance. The number of gas mols is constant while the number of mols of solid products increases , and as a result the gas proportion is reduced with better oxygen balance. ( High velocity explosives in composition with Aluminum trade some brisance for enhanced blast. The optimal amount is around 18 to 20 percent which yields a third of detonation products as solid alumina.) This also occurs for the stoichiometric mixture , with 8 mols NaClO3 , where best performance will likely be seen.

The following values in kilocalories per mol are applied for thermodynamic calculations
- 94 for CO2 , - 26.4 for CO , - 57.8 for H2O

Ca2(C7H5O2)2(ClO3)2 = mol wt. 489 , NaClO3 = mol wt. 106.5 . . . . . . . . . . . . . . . . . . . . . . .∆H / mol wt. . . . . . . .solid mols / total of mols


Ca2(C7H5O2)2(ClO3)2 + 3 NaClO3 => CaO + CaCl2 + 3 NaCl + 14 CO + 4 H2O + H2 . . . . . . 601 / 809 . .~ 0.74 , . . . . % solids . .~ 21

Ca2(C7H5O2)2(ClO3)2 + 4 NaClO3 => CaO + CaCl2 + 4 NaCl + 2 CO2 + 12 CO + 5 H2O . . . 794 / 915 . . ~ 0.87 , . . . . % solids . .~ 24

Ca2(C7H5O2)2(ClO3)2 + 5 NaClO3 => CaO + CaCl2 + 5 NaCl + 5 CO2 + 9 CO + 5 H2O . . . 986 / 1022 . . ~ 0.96 , . . . . % solids . .~ 27

Ca2(C7H5O2)2(ClO3)2 + 6 NaClO3 => CaO + CaCl2 + 6 NaCl + 8 CO2 + 6 CO + 5 H2O . . .1199/ 1128 . . ~ 1.06 , . . . . % solids . .~ 30

Ca2(C7H5O2)2(ClO3)2 + 8 NaClO3 => CaO + CaCl2 + 8 NaCl + 14 CO2 + 5 H2O . . . . . . . 1605 / 1341 . . ~ 1.2 , . . . . . % solids . .~ 34

12 : 21 parts by weight

Dividing the mol weight of the stoichiometric mixture 1341 by the mol weight of each of the preceding mixtures individually , you obtain a factor by which to multiply it's ∆H value , thus normalizing the shown values for an equal weight of material ( 1341 ) in every case. This works out to 996 ∆H for 3 mols NaClO3 , 1164 ∆H for 4 mols , 1293 ∆H for 5 mols , 1425 ∆H for 6 mols.


.

[Edited on 15-6-2014 by franklyn]

new use for tetraphenylborates!

halogen - 15-6-2014 at 09:46

Naively I think the stability of the molten stuff is repulsion between fuel anion and oxydizer anion. In order to get a neutral intermediate, MO(-) breaks off leaving either PhC=O (+) or the chloryl cation, or some radical. If that's true, perhaps the properties and stability could be fine tuned, deliberately and science like. Patents cost and if it's obvious to me it's obvious.

Phthalate and terphthalate with two carboxylates: dead weight, but maybe less reactive?

Gallates used to be used in whistle composition, and salicylates. I'd guess those are worth investigating in the molten MClO3 or 4 mixture, and common too.

If we want to get baroque there are the anisic acids, aminobenzoic, etc.

I doubt the arylsulfonates have [had any reason to] been tried in pyrotechnic compositions before. And if we want to be absurd, tetraphenylborate salts are known.

[Edited on 15-6-2014 by halogen]

franklyn - 15-6-2014 at 17:16

Along the same lines I thought of this , mixing Calcium Chlorate and Calcium Picrate
to form a double salt with a much improved oxygen balance. Perchlorate would do
nicely also. Though it's been contemplated by some , melting picrate salts seems
risky , www.sciencemadness.org/talk/viewthread.php?tid=6551
Formation from cold solution seems the proper route.

2 Ca(ClO3)2 + 2 Ca(C6H3N3O7)2 => 2 Ca(ClO3)2 (CaC6H3N3O7)2


Calcium Chlorate Picrate.gif - 2kB

=> 2 CaO + 4 CO2 + 8 CO + 2 H2O + 3 N2 + Cl2

____________________________________________


While on this subject , another possible double salt using Calcium to link Trinitromethane with Trinitrophenol.

Calcium Picrate Trinitromethane.gif - 3kB

=> CaO + 4 CO2 + 3 CO + H2O + 3N2
.

[Edited on 16-6-2014 by franklyn]

Dornier 335A - 16-6-2014 at 04:00

PHILOU Zrealone, the mixture ignites at more than 250°C. I'm sure there won't be any water left in the liquid.

I believe the goal is to find the best compromise between homogeneity of the mix, oxygen balance and actual usefulness. The molten mixture is homogeneous and can have perfect oxygen balance (I mixed mine to -10%), although not very useful in practice due to the high melting point.

I was able to detonate melted and quickly solidified flakes of the mixture, but those are likely to be less homogeneous. What about cooling the liquid down faster, like dripping it into liquid nitrogen?

Double salts' complete homogeneity even in the solid state is indeed interesting Franklyn. I think smaller or better oxygen balanced anions are the way to go with chlorate, rather than mixing the double salt with excess chlorate afterwards. Using calcium as the cation might be problematic because the benzoate crystallizes with water and the chlorate is very hygroscopic.

I will try a mixture (preferably molten or cast) of NaClO3 and calcium picrate as soon as possible, hopefully this week. My theoretical calculations say it will have exceptionally high performance (>8000 m/s at max density). KClO3 or NaClO3 and potassium picrate is also on my list.

Dornier 335A - 19-6-2014 at 12:19

Okay, I've synthesised three metal picrates now: potassium, calcium and sodium. I tried combinations with sodium and potassium chlorate. Below you can see melting points and ignition points for the ingredients:

Data from Urbanski, Fedoroff and Wikipedia

The criteria for a mixture like KClO3/sodium benzoate seem to be the following:
- At least one of the components have to be molten at the ignition point.
- The fuel and oxidizer have to be compatible in the melt.
- The oxidizer should not decompose first, otherwise bubbles will form.
- And finally the mixture should detonate fairly easily.

Only one of the six mixtures fulfilled all four criteria and gave satisfactory results. It was potassium chlorate and sodium picrate, 50/50 by weight. One milligram confined in aluminium foil and heated briefly in a flame exploded with incredible power, turning the foil into hundreds of fragments. Potassium chlorate and potassium picrate ignited before melting. Sodium chlorate and potassium picrate started to bubble and detonated very seldom. Calcium picrate behaved very strangely. It deflagrated only slowly, even though Fedoroff wrote it "explodes violently at 323-28°". A mixture with potassium chlorate could detonate if confined well enough and heated quickly, but its brisance was not very impressive.

One mixture which could work is sodium chlorate and copper picrate; copper picrate is said to explode violently at 282-287°C. (I know copper/chlorate is generally a bad idea but it's worth a try.)

Fantasma4500 - 20-6-2014 at 03:06

copper and chlorate? you sure this isnt because it could by accident get near ammonia and form the primary explosive tetraammine? when i get all the acid out of my copper chloride ill attempt to make copper chlorate, i recall it has even been sold in smaller amounts for use in exotic fireworks
and if pyrotechnicians dares to handle it, then there shouldnt be that much worries about it
but again, you cant get smarter by assuming you know it all

jjgoh - 25-7-2014 at 07:52

This type of composition is very powerful when melted and it does explode but not deflagaration.
I Wonder can I twist the formula in order to make it explode in no time when a fire near to iit.
Currently using this formula :
Potassium Chlorate = 7.11%
Sodium benzoate = 2.99%
.

KClO3 is laboratory grade where sodium benzoate is food grade which is obtain from a bakery shop

TheChemiKid - 26-7-2014 at 05:08

What is the other 90%, or did you make a mistake?