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Author: Subject: Some old English patents appertaining to mixtures intended to substitute primary explosives
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[*] posted on 20-1-2010 at 05:46
Some old English patents appertaining to mixtures intended to substitute primary explosives


In the section about explosives in Thorpe's A dictionary of applied chemistry, there is mention of several patents regarding mixtures that are intended as replacements for primary explosives, like mercury fulminate, in blasting caps/detonators, an interesting but relatively little known or talked about subject:

http://books.google.com/books?id=MgA5AAAAIAAJ&pg=PA84&am...

"Mixtures, without fulminate, containing aluminium, have been proposed by Führer (Eng. Pat. 2755, 1901, and 24812, 1902), Bielefeldt (Eng. Pat. 7148, 1901), and von Dahmen (U.S. Pat. 702357, 1902), but these mixtures require very strong confinement to be effective; the Westfälisch - Anhaltischc Sprengstoff Actien-Gesellschaft have patented mixtures without fulminate, containing potassium chlorate with mono-, di-, or tri-nitrocresol, &c.; and Bielefeldt (Eng. Pat. 23889, 1901) suggests a mixture of potassium chlorate with trinitronaphthalene." (volume 3, page 84, 1922 edition)

I have been able to locate the von Dahmen U.S. patent mentioned by Thorpe:

http://www.google.com/patents?id=qnoPAAAAEBAJ&printsec=a...

Unfortunately, the patent omits a few important details, such as:

1) What's the container to be used for the mixture? A metal tube or capsule, such as used in ordinary blasting caps, or can it also be made out of other materials? (the age of the patent seems to rule out such things as plastics, so I assume he was likely using copper tubes or capsules.)

2) Is it necessary to apply any pressure to the mixture after loading it into the container?

3) Perhaps I am interpreting the inventor's words too literally here, but how is a "hermetically sealed space" achieved in such a device that can be set off by means of a "strong powder fuse" (a black powder fuse, I suppose)? It will leave an orifice of some kind, no matter how small the diameter of the fuse is. Thorpe says that "these mixtures require very strong confinement to be effective", but "very strong confinement" does not necessarily mean "hermetically sealed".

Jahred Ledgar, in The Preparatory Manual of Black Powder and Pyrotechnics, page 256, after giving more specific instructions on how to prepare a batch of this mixture, says:

"To use, it simply needs to be pressed into any blasting cap or detonator housing under the usual means."

Not sure if this is a very reliable source, though, particularly on a subject as comparatively little known as this. If anyone around here has actual experience with this mixture perhaps he/she could clarify some of these points.

Incidentally, I found another patent of von Dahmen, also about the topic of detonating high explosives without using fulminates, that is not mentioned by Thorpe:

http://www.google.com/patents?id=5B1QAAAAEBAJ&printsec=a...

It's a different mixture and method, which apparently consists of combining a mixture of ammonium nitrate, di or tri nitrotoluene and aluminum with a mixture that looks like a sort of modified black powder (sulfur, carbon, potassium nitrate and lead peroxide), then strongly confining it and setting it off with a black powder fuse.


I have not been able to find any of the English patents mentioned by Thorpe. I was only able to find bits of information about some of them in several places.

Regarding Eng. Pat. 20755 (not 2755, as is misprinted in Thorpe's Dictionary) I found this:

"Detonating Composition To Replace Fulminate Of Mercury.— This composition is the invention of Herr J. Fuhrer of Vienna, and it is intended for use in place of fulminate of mercury for producing the initial detonation necessary for firing a charge of high explosive. It is very much safer to handle than fulminate of mercury and the inventor claims it will satisfactorily detonate the high explosives. If so, the gain will be very great. One of the great dangers in handling high explosives has been the sensitiveness of the fulminate fuze or detonator, and no satisfactory detonator not containing fulminate of mercury has (unless this proves to be the long sought article) been obtained. The materials used are copper, ammonium nitrate, potassium nitrate, sulphur and aluminum. One formula specifies 30 to 40 parts of copper-ammonium nitrate, 42 to 25 parts of nitrate of potassium, 10 to 7 parts of sulphur, and 18 to 28 parts of metallic aluminum. The date of acceptance of the British patent (No. 20,755) is December 31, 1901." (Proceedings of the United States Naval Institute, Volume XXVIII, Part 1, page 145.)

Thus it appears to be the same mixture, or at least very similar, as U.S. Pat. 702357.

Regarding patent 24812, I found this in a German book:

Die Erfindung betrifft einen Zundstoff fur Sprengkapseln und Zwischenladungen, bestehend aus 45.5 Teilen Kaliumnitrat, 30 Teilen Kaliumbikarbonat, 16 Teilen Schwefel und 8.5 Teilen Aluminum.(Dr. Alfred Stettbacher, Dr. Richard Escales, Initialexplosivstoffe, 2002 reprint. pp. 214-215.)

Loosely translated (with the aid of Systran 6):

"The invention concerns an explosive for blasting caps and intermediate loads (?), consisting of 45.5 parts potassium nitrate, 30 parts potassium bicarbonate, 16 parts sulfur and 8,5 parts aluminum."

So it appears to be a sort of modified "pulvis fulminans". Unfortunately, the book does not give any information of how is the mixture of the above substances made and employed in blasting caps.

I couldn't find anything about Eng. Pat. 7148 (this number is very likely a misprint) by Bielefeldt.

Regarding Eng. Pat. 23889, by the same inventor (Bielefeldt), I was able to find this:

"Patent 23889 vom gleichen Jahre verwendet statt Knallquecksilber Mischungen aus Trinitronaphthalin und Kaliumchlorat." (Dr. Alfred Stettbacher, Dr. Richard Escales, Initialexplosivstoffe, 2002 reprint. Page 204.)

Which loosely translated (again with the aid of Systran 6) is:

"Patent 23889 from the same year uses mixtures of trinitronaphthalene and potassium chlorate instead of mercury fulminate."

The following from another source was a bit more informative:

"Percussion Caps and Detonators; Priming Compositions or Charges for . M. Bielefeldt, Berlin. Eng. Pat. 23,889, Nov. 25, 1901.
Finely pulverised trinitronaphthalene (70 per cent, to 85 per cent.) is mixed with finely pulverised potassium chlorate (15 per cent, to 30 percent.) and sufficient gum solution to form a paste of the desired consistency." (Journal of the Society of Chemical Industry, Volume 21, Oct. 15, 1902. Page 1246.)

This gives the proportions of the materials, but it does not give details of how is it used in detonators.

If anyone around here has access to these English patents, please let me know.
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[*] posted on 20-1-2010 at 05:58


I would be very cautious of potassium chlorate mixtures.
They can be quite sensitive and unstable with mixtures with sulphur being particularly nasty.
Chlorates have caused a lot of lab accidents over the years.
At one time it was commonly heated with managanese dioxide to produce oxygen. Normally the reaction would proceed without problems but contamination of the manganese dioxide or the molten chlorate coming into contact with the rubber stopper or tubing could result in disaster.
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[*] posted on 20-1-2010 at 06:11


Quote: Originally posted by ScienceSquirrel  
I would be very cautious of potassium chlorate mixtures.
They can be quite sensitive and unstable with mixtures with sulphur being particularly nasty.
Chlorates have caused a lot of lab accidents over the years.
At one time it was commonly heated with managanese dioxide to produce oxygen. Normally the reaction would proceed without problems but contamination of the manganese dioxide or the molten chlorate coming into contact with the rubber stopper or tubing could result in disaster.


Only one of the mixtures in the patents described above uses a chlorate, and there is no sulphur in it.

I have handled several chlorate mixtures before. One that never gave me any trouble and is easy to make is Berge's blasting powder:

http://books.google.com/books?id=qJHhhBwf5H8C&pg=PA330&dq=%22berge's+blasting+powder%22&cd=1#v=onepage&q=%22berge's%20blasting%20powde r%22&f=false

No sulfur involved, just sugar, a chromate (speeds up the reaction), some wax (paraffin works) and the chlorate. Just don't get too cocky and think it's 100% safe. Given a blow strong enough it can detonate.
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[*] posted on 20-1-2010 at 09:49


Here's two of the old British patents

Attachment: GB23889 Detonating composition, Bielefeldt circa 1901.pdf (131kB)
This file has been downloaded 1265 times

Attachment: GB24812 Detonating Composition , circa 1902 Fuhrer.pdf (183kB)
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[*] posted on 20-1-2010 at 10:08


Quote: Originally posted by Rosco Bodine  
Here's two of the old British patents


Thanks!

Just out of curiosity, where did you find them? I looked on the net quite a bit but with no results.
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[*] posted on 20-1-2010 at 10:23


ESPACENET using a name search, the indexing for the older patents sometimes uses an archival number having the year as prefix and a letter added as suffix to the actual patent file number. Therefore a straight number search won't bring it up, but a name of inventor search may get a search hit.

What may occur with some of these old "fulminating powder" type of detonating compositions is that only a low order detonation is achieved, especially for the smaller charges. There really is no substitute pyrotechnic mixture which can do the same job as a bona fide primary detonating explosive which has a far greater self-acceleration and ultimate velocity from a very small distance and time requirement from ignition to "run-up" to full velocity and output. A pyrotechnic
composition which may marginally be able to do the job is a curiosity more than being any genuine equivalent substitute in terms of performance.

(by weight) KClO3 5 parts and potassium ferricyanide 3 parts is a fulminating mixture.

[Edited on 20-1-2010 by Rosco Bodine]
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[*] posted on 20-1-2010 at 21:25


Quote: Originally posted by Rosco Bodine  
ESPACENET using a name search, the indexing for the older patents sometimes uses an archival number having the year as prefix and a letter added as suffix to the actual patent file number. Therefore a straight number search won't bring it up, but a name of inventor search may get a search hit.


Thanks for the tip. I had stumbled upon that site before. Their indexing is a bit awkward. I was searching for the patent numbers in question (as quoted by Thorpe and the other sources above), so I got no results.


Quote:

What may occur with some of these old "fulminating powder" type of detonating compositions is that only a low order detonation is achieved, especially for the smaller charges. There really is no substitute pyrotechnic mixture which can do the same job as a bona fide primary detonating explosive which has a far greater self-acceleration and ultimate velocity from a very small distance and time requirement from ignition to "run-up" to full velocity and output. A pyrotechnic composition which may marginally be able to do the job is a curiosity more than being any genuine equivalent substitute in terms of performance.


Even though the subject is rather "arcane" and comparatively little known, the number of inventors claiming success in detonating at least several types of high explosives or explosive mixtures without using primary explosives is rather interesting and, in my opinion, worthy of further inquiry as a possible alternative. It is also interesting that at least as early as the early 1870s, less than 10 years after Nobel introduced the fulminate blasting cap, we already have inventors trying to do away with it by using mixtures that, they claim, were more or as effective and less dangerous to handle.

Quote:
(by weight) KClO3 5 parts and potassium ferricyanide 3 parts is a fulminating mixture.


Yes, a similar mixture, but with potassium picrate added in (invented earlier by Designoble and Casthelaz, but who apparently had not fully realized its potential use as an initiator) was already used by Prudencio Castellanos in the 1870s to detonate dynamites:

http://www.google.com/patents?id=2C9tAAAAEBAJ&printsec=a...

He called his devices "percussive petards". He made them both out of metal capsules as well as of cardboard tubes. The percussive mixtures he used do not require pressure after being loaded in the containers, and seem to work best granulated.

Something that Castellanos says in his patent also struck me as curious: even black powder charges were apparently being used to attempt to detonate dynamites. It doesn't seem that the fulminate blasting cap was as universally accepted as one would think from reading most history books on the subject.
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[*] posted on 20-1-2010 at 22:59


Probably MF was quite expensive; there were some terrible accidents asociated with it's manufacture, and they must have been trying to find new alternatives. After all, dynamite can go off even with BP. With the development of new explosives they must have realised that a real primary is needed for reliable work, and not some fart-fulminating mixtures.

The caps for the gun cartridges are a different story; all it's needed there is a flame to ignite the propellant, so chlorate based mixture were used, till the bore corrosion was observed.
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[*] posted on 20-1-2010 at 23:40


Quote: Originally posted by a_bab  
Probably MF was quite expensive; there were some terrible accidents asociated with it's manufacture, and they must have been trying to find new alternatives. After all, dynamite can go off even with BP. With the development of new explosives they must have realised that a real primary is needed for reliable work, and not some fart-fulminating mixtures.


It does not seem to be as simple as that. According to Castellanos' statements, black powder charges seem to have been very little reliable, igniting the dynamites rather than making them explode. Plus back then other explosives were already known. That didn't seem to stop these inventors from seeking a safer alternative to mercury fulminate compressed in a cap. Some of these patents are even from the early 1900s, and specifically mention explosives like guncotton, picric acid, and ammonium nitrate mixtures, and such detonating/fulminating/percussive mixtures were still being tinkered with and used. The increasing variety of explosives does not seem to have deterred such investigations.
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[*] posted on 21-1-2010 at 09:28


HNM is almost a primary explosive!
It will detonate from a hot flame (hmmm, sense of déja vu here) and was used as a base charge, initiated by a suitably hot flash powder.
AFAIK, this type of detonator used a steel tube as containment.
while HNM is much less shock-sensitive than fulminate or azide it still needs some care in handling.


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[*] posted on 21-1-2010 at 11:37


There are progressive density and diameter loading schemes using strong confinement to cause a shortened runup DDT distance for PETN, probably also adaptable to other near primary explosives like nitromannite and nitroinositol,
all three of which are also detonable by pyrotechnic initiators via a combination
of cookoff and impulse, communicated directly or via flyer plates across a short airgap. Regular 60/40 perchlorate/aluminum flash will initiate sensitive explosives
with confinement, but so will the snap of a good electrical arc which will cookoff
NG nicely. There are a few ways around having to use a primary explosive as the means of initiation, which are alternatives to the more conventional use of a primary to get the job done. However it still remains true that using a primary which is best suited for the task is the simplest, surest, and most economical solution.
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[*] posted on 21-1-2010 at 20:56


Quote: Originally posted by hissingnoise  
HNM is almost a primary explosive!
It will detonate from a hot flame (hmmm, sense of déja vu here) and was used as a base charge, initiated by a suitably hot flash powder.
AFAIK, this type of detonator used a steel tube as containment.
while HNM is much less shock-sensitive than fulminate or azide it still needs some care in handling.


I once exchanged personal messages with a guy who used similar methods but with erythritol tetranitrate.

Tri and tetra-nitronaphthalene also can detonate with heat. The patent by Bielefeldt seems to use this method but with a mixture of potassium chlorate.

[Edited on 22-1-2010 by Blasty]
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[*] posted on 22-1-2010 at 11:59


It would be interesting to see how chlorate+X compares to various primary explosives in the drop test. If an explosive is sensitive to impact it should be able to detonate and if it is
easy to ignite it might be a primary.

chlorate+fulminate is less sensitive than straight fulminate,
the same likely applies to ones like HMTD.

chlorate+TNT is probably more sensitive than TNT but
how much? Its difficult to see chlorate and nitrated napthalene doing much.

To make a primary the mixture should also be easy to ignite,
so the melting points of the ingrediants should be high
or else the heat of melting will absorb too much of the energy.

Someting like chlorate + phosphorus is quite
sensitive and can work in percussion primers like fulminate
it is probably a primary.

An interesting one to try would be chlorate+picrate salts
so see if it works any better than the straight picrate.
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[*] posted on 22-1-2010 at 14:47


The simple clathrate of basic lead picrate/lead nitrate/lead chlorate is more energetic on detonation than anhydrous lead picrate or basic lead picrate alone.

Possibly in mixture with nitromannite or some other sensitive and near primary sensitivity nitroester or similarly sensitive
HE, the binary mixture composition with a relatively mild primary would basically become a fuse sensitive HE binary capable of rapid DDT for high order and high output.

However the danger, potential instability, and sensitivity is usually greater for mixtures of chlorate or perchlorate or other oxidizers with ordinary fuels or energetic oxygen deficient explsoive fuels, than is comparable for other compounds used in mixture to achieve a synergistic effect.
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[*] posted on 22-1-2010 at 22:36


Quote: Originally posted by gregxy  
Its difficult to see chlorate and nitrated napthalene doing much.


Tri and tetra-nitronaphthalene can detonate with sudden heat:

"Trinitronaphthalene... is insoluble in water, only slightly soluble in alcohol and ether; precipitated in flocks from solution in fuming nitric acid. The crystals decrepitate when heated, melt at 214° with partial sublimation, and detonate at a higher temperature.

Tetranitronaphthalene... is produced by heating a solution of trinitronaphthalene in fuming nitric acid for four days in closed vessels, and crystallises from hot alcohol in long asbestos-like needles, which melt at 200°, detonate violently at a higher temperature, and are coloured deep red by alcoholic ammonia." (Henry Watts, A dictionary of chemistry, Volume 6, 1879 edition. pp. 848-849)

"M. Berthelot has shown that substances, which, by gradual increase of temperature, are not explosive, such as picric acid, trinitronaphthalene, potassium chlorate, etc., can nevertheless be caused to explode if they are suddenly heated to a much higher temperature than is necessary to bring about decomposition." (Heinrich Brunswig, Explosives: a synoptic and critical treatment of the literature of the subject as gathered from various sources, 1912. page 33.)

This seems to be the property that Bielefeldt was using by mixing it with potassium chlorate and setting it off in a confined space.

Quote:
It would be interesting to see how chlorate+X compares to various primary explosives in the drop test. If an explosive is sensitive to impact it should be able to detonate and if it is
easy to ignite it might be a primary.

An interesting one to try would be chlorate+picrate salts so see if it works any better than the straight picrate.


There is some conflicting info about this in old books and patents. Some, like Designoble, Castellanos, etc., seem to have been very convinced that such mixtures were safer to prepare and use than mercury fulminate. I have found others who claim these mixtures of picrate + oxidizers are too sensitive to be useful. However, the critics of these mixtures usually refer to the manufacture and use of them as the main charge in artillery shells, torpedos, etc. which require larger quantities. The only class of such mixtures that met with general approval were the ammonium picrate + potassium nitrate mixtures.

According to the following statements, some mixtures of picrates and chlorates are not only more powerful than the picrates alone, but more powerful than mercury fulminate, and almost like nitroglycerine:

"About 35 parts of carbozotate of potassa (potassium picrate)
18 parts of ferrocyanide of potassium
47 parts of chlorate of potassa

This last powder is nearly three times as powerful as the fulminate of mercury." (Designoble and Casthelaz, U.S. Pat. 76173)

The above mixture is the one that Castellanos preferred to use in his "percussive petards". Unfortunately, none of these inventors gives details of how exactly did they mix and granulate these materials (it goes without saying that they must have been worked wet.) Designoble & Casthelaz just say that these mixtures are prepared pretty much like black powder.


"Potasium Picrate.—Most violently explosive of the picrates. Potassium picrate and potassium chlorate form a mixture nearly as powerful as nitro-glycerine, but it is so sensitive to friction or percussion as to render it practically useless. With potassium nitrate instead of chlorate a less violent mixture is obtained, but one still too liable to accidental explosion." (Walter Nickerson Hill, Notes on certain explosive agents , 1875. Page 49.)

"The potassium salt is that most easily prepared, on account of its very slight solubility in water. It is also one of the most highly explosive. When mixed with oxidising agents, and especially with potassium-chlorate, it furnishes very powerful explosive materials; indeed, the chlorate mixture approaches nitro-glycerine and gun-cotton nearly in violence of action than any other explosive agent produceable on a practical scale. This mixture is, however, so susceptible of detonation by friction or concussion as not merely to render its employment in shells impossible, but also to preclude its application to any purpose without the adoption of very special precautions." (Professor Abel on Explosive Agents, The Chemical news and journal of industrial science, V. 24 , 1871, pp. 127-128)

I wonder if perchlorates, instead of chlorates, could be used in such mixtures to make them safer? I haven' t found anything on the subject yet.



[Edited on 23-1-2010 by Blasty]
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[*] posted on 23-1-2010 at 02:42


You will be able to confirm by experiment that those early references are not reliable. The power described for such mixtures is an exaggeration. One of the real disadvantages which will be encountered is that the critical mass required for the transition from low order to high order detonation will be excessive, so that the physical dimensions of what would become a useful device reliable as a blasting cap is more like the dimensions of a booster, for example in the range of tens of grams of the mixture being required for some of these contemplated schemes. Perchlorate would probably be safer than chlorates. There is probably an inherent risk of spontaneous decomposition and perhaps spontaneous ignition
which is a real concern for such mixtures.

There is a significant difference between "explosion" and "detonation" just like there is a significant difference between a low order detonation and a high order detonation. Bona fide primary explosive compounds having small critical mass and diameter are exponentially more effective and are safer and more practical
than any pyrotechnic mixtures.
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[*] posted on 23-1-2010 at 04:47


Quote: Originally posted by Rosco Bodine  
You will be able to confirm by experiment that those early references are not reliable. The power described for such mixtures is an exaggeration.


Are you aware of anyone who has tested them more recently?


Quote:
One of the real disadvantages which will be encountered is that the critical mass required for the transition from low order to high order detonation will be excessive, so that the physical dimensions of what would become a useful device reliable as a blasting cap is more like the dimensions of a booster, for example in the range of tens of grams of the mixture being required for some of these contemplated schemes.


Unfortunately, these inventors often do not specify how much of their mixtures are supposed to be used when employed as detonators. In other cases some of these detonating mixtures were stated to be used in quantities that range from less than a gram to about 2 or 3 grams. Von Dahmen, for example, claims that 2 to 3 grams of his copper-ammonium nitrate mix are enough to detonate dynamites, picric acid explosives and ammonium nitrate mixtures.
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[*] posted on 23-1-2010 at 08:14


No I don't know of any tests being done for these pyrotechnic mixtures.

Patent claims do not necessarily tell the whole true story and all of the
explosives mentioned are capable of low order detonation schemes,
which is likely what would be the result from their inititiation by
one of these alternative detonators.
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[*] posted on 23-1-2010 at 14:02


Michael Swisher wrote a short monograph entitled "Brisantly Explosive Pyrotechnic Compositions" in Pyrotechnica XVI. He covers a number of different mixtures used throughout time; from various "flash" powders to dark report comps as well as those based on K4Fe(CN)6 and K3Fe(CN)6 mixed with KClO4.

An interesting reference is to co-precipitated (from mixed warm aqueous solutions dropped out by addition of 2-propanol) intimate mixtures. A patent secured by John W. Fronabarger (per Unidynamics/Phoenix, Inc.) is attached below.

A strong word of caution. Co-precipitation of an oxidiser and fuel often leads to unexpectedly sensitive mixtures, some even while "wet". Speaking from personal experience, should one desire to play in this area, start out with very small quantities with efficient agitation, protected by appropriate safety gear and a shield.


Attachment: 3793100_IGNITER_COMPOSITION_COMPRISING.pdf (121kB)
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[*] posted on 23-1-2010 at 21:31


Quote: Originally posted by argyrium  
Michael Swisher wrote a short monograph entitled "Brisantly Explosive Pyrotechnic Compositions" in Pyrotechnica XVI. He covers a number of different mixtures used throughout time; from various "flash" powders to dark report comps as well as those based on K4Fe(CN)6 and K3Fe(CN)6 mixed with KClO4.


You wouldn't happen to have a scan of that article, would you?

Quote:
An interesting reference is to co-precipitated (from mixed warm aqueous solutions dropped out by addition of 2-propanol) intimate mixtures. A patent secured by John W. Fronabarger (per Unidynamics/Phoenix, Inc.) is attached below.


Thanks. It's an interesting piece. I notice, however, that the mixtures of ferricyanide containing perchlorate instead of chlorate do not seem to be detonating (by adding potassium picrate they very likely would, though.) I have noticed this more "tame" behavior of perchlorates before when dealing with sugar mixtures. Earlier in the thread I mentioned Berge's blasting powder, which burns very fast, in a flash. Even though that mixture is relatively safe to make and handle, a while back I thought about coming up with an even safer updated version using potassium perchlorate, but it was rather difficult to achieve even a decent approximation to the performance of the original chlorate mix. For starters, chromates do not seem to speed up the reaction between perchlorates and sugar. Using dichromates seems to speed up things a bit, but the combustion is still too slow. By replacing some of the sugar with finely pulverized charcoal I was able to get a more decent deflagration speed, but still inferior to the original Berge's powder. Perchlorates are safer, but they come at a price in speed.


Quote:
A strong word of caution. Co-precipitation of an oxidiser and fuel often leads to unexpectedly sensitive mixtures, some even while "wet". Speaking from personal experience, should one desire to play in this area, start out with very small quantities with efficient agitation, protected by appropriate safety gear and a shield.


Care to elaborate on which of these precipitated mixtures you've found particularly dangerous to deal with?
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[*] posted on 24-1-2010 at 03:45
Two Component Instant Detonator


Whatever the application of secondary explosives may be , the use of
a primary explosive detonation initiator is unavoidable without invoking
exploding bridgewires. For military applications the search for what are
termed insensitive explosives remains compromised by the properties
of the primary explosive initiator. In civilian use the work around has
been to segregate detonators from the main charge until just before
setting off the explosion. Fuzes are similarly only attached to ordnance
before actual use and the two are never stored assembled.

I had thought that the binary gas artillery shell design could be applied
to binary or Sprengel type explosives. The mixing to be done during flight
thus there is no risk from recoil and setback upon firing. Such a munition
would be safer for transport and storage than anything in use now.
Explosives for civilian use such as mining are not amenable to such
techniques. Precedents of the use of binary explosive mixtures as a main
charge are ill conceived , the components are invariably reactive liquids
which introduce additional problems in place of the issue of sensitivity. A
consideration which is not dealt with is what to do with the mixture once
it is made , since it cannot readily be deactivated , it's disposal becomes
very problematic.

It has subsequently occurred to me that this is actually quite perverse in
its conception since it is a contrived solution to the primary issue , the
sensitivity of the initiating explosive. Primary explosives whatever their
merits are always a compound made for the purpose , which is then
distributed for it's intended use just as it is. It may seem an oxymoron to
have an insensitive primary explosive since that then transcends into the
realm of secondary explosives. Why not have instead a detonator
comprising a two component primary explosive that is mixed in the act
of arming or priming. For electric detonators this could certainly even be
done remotely. This idea is surely not original and must have been
addressed many times although no mention of the topic or investigation
of it can be found. Compositions that have seen limited application as a
main charge , although shock sensitive are not primary initiating explosives.

A detonating cap should also not present any greater risk or special
handling than existing types when there is a need to remove it from
a secondary charge. Procedures providing an instant explosive on
demand for such a device , comprised of safe components which if
mixed remain stable , requiring only ordinary cap safety handling if it
is not immediately used , have certainly been known but dismissed as
curiosities and their potential application has remained unrecognized.

A likely candidate would be a Metal salt of Nitromethane , which are
described in references as powerful detonating primary explosives. The
requirement for absolute anhydrous conditions has doubtlessly relegated
their synthesis and consideration for practical use to obscurity.
Nitromethane reacts with Calcium Hydride producing Calcium Nitromethanide
http://gallica.bnf.fr/ark:/12148/bpt6k3133k.image.f1034.lang... - translated below
on demand evolving only Hydrogen gas. The notion of applying this synthesis
in situ becomes viable since the reaction remains encapsulated , dispensing
with the main detraction , this primary's reactivity to moisture and air.
http://membership.acs.org/c/chas/jchas_archives/1995/2(1)/1995-2-1urben-blast.pdf
In a related thread see Quote( By Vorion )
https://www.sciencemadness.org/whisper/viewthread.php?tid=50...

In a previous post I outlined some mixtures which suggest another
approach , to have a volatile component of a Sprengel explosive
which can be vented to deactivate the explosive potential.
http://www.sciencemadness.org/talk/viewthread.php?tid=5777#p...
Fashioning a workable detonator is just a matter of engineering. Whether
these later ingredients are able to produce a high order detonation is
not personally known to me , but that some similar combination can
I have no doubt.


Comptes Rendus de Académie des sciences 1925, 180, 1034-1036

ACADEMIE DES SCIENCES

Organic Chemistry - Reduction of Nitro Compounds by Calcium Hydride
Note (4) J. F. DURAND , S. HOUGHTON

(4) Science 23 Mar 1925

Nitro derivatives of the Acyl series. - Nitromethane dissolved in cold
Ether and treated with powdered CaH2 gives a vigorous evolution of
hydrogen. Exactly 1 molecule of hydrogen is gathered for every
molecule of nitromethane; this last body becomes a salt of calcium.

2 CH3.NO2 + CaH2 -> (CH2NO2)2Ca + 2 H2

.
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Rosco Bodine
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[*] posted on 24-1-2010 at 04:12


The use of actual compounds which contain the desired functional groups in each molecule can eliminate variables which can cause more unpredictability about the potential behavior of physical mixtures. You cannot achieve a more intimate mixture than to include the oxidizer at the molecular level within the structure of the explosive fuel component,
where the two are married as a compound. Mixtures certainly can have their usefulness. However, in my experience the performance is better if the properties for which a synergy is being sought can be achieved by combining the desired properties by embodiment within an actual compound at the molecular level, or at the next closest state of microscopic subdivision, such as inclusion by microcrystalline lattice structure entrapment, where a quasi-molecular electrostatically bonded complex crystal inclusion compound known as a clathrate, nearly as intimately combines the separate materials as if they were a conventional compound. Basic lead salts of polynitrophenolic compounds are capable of forming complex multiple salts and clathrates. I have experimented with a few of the many different possible multiple salts and clathrates all of which are primary explosives which behave more or less like
lead styphnate. They are almost, but not quite there in
terms of self-accelleration, to be useful as initiating explosives, close enough to being what is desired that it
remains interesting to investigate by experiment predicted
complex salts of these types which have not been reported in the known literature.

I have made the tertiary clathrate [basic lead picrate - lead nitrate - lead chlorate]

And it was my observation that it would be interesting to experiment further and see if a binary clathrate or double salt complex was possible for the nitrate, and for the chlorate, possibly for a perchlorate as well. Only the binary for the nitrate variant was investigated by experiment, which was a confirmation of an already published compound.
See attached patent US2175249 example #2.

The chlorate variant and the perchlorate variant may also be possible as analogues of the nitrate variant of example #2.

A styphnate based material of similar composition may be possible also.

A double salt of lead styphnate and lead picrate may be possible.

Complex derivative variants of a basic form of that possible double salt may also exist, as is hypothesized for the basic lead picrate variant above, and the chlorate and perchlorate analogues for example #2 of the patent.

Nickel Styphnate - Potassium Styphnate double salt should be investigated, as well as the possible? Nickel Styphnate - Lead Styphnate double salt.

The chemistry and potential value for such unreported potential compounds, along with some of the double fulminates, is more intriguing to me anyway, than is the
physical blending of pyrotechnic mixtures......which somehow only seems like so much effort at putting more flash and crack
in a glorified flashcracker :D

Attachment: US2175249 Lead Nitrato-Bis Basic Lead Picrate ex.2 .pdf (177kB)
This file has been downloaded 1339 times

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[*] posted on 20-2-2010 at 09:33
Animaniacs Bad idea son.


Quote: Originally posted by Blasty  


"Detonating Composition To Replace Fulminate Of Mercury.— This composition is the invention of Herr J. Fuhrer of Vienna, and it is intended for use in place of fulminate of mercury for producing the initial detonation necessary for firing a charge of high explosive. It is very much safer to handle than fulminate of mercury and the inventor claims it will satisfactorily detonate the high explosives. If so, the gain will be very great. One of the great dangers in handling high explosives has been the sensitiveness of the fulminate fuze or detonator, and no satisfactory detonator not containing fulminate of mercury has (unless this proves to be the long sought article) been obtained. The materials used are copper, ammonium nitrate, potassium nitrate, sulphur and aluminum. One formula specifies 30 to 40 parts of copper-ammonium nitrate, 42 to 25 parts of nitrate of potassium, 10 to 7 parts of sulphur, and 18 to 28 parts of metallic aluminum. The date of acceptance of the British patent (No. 20,755) is December 31, 1901." (Proceedings of the United States Naval Institute, Volume XXVIII, Part 1, page 145.)




Can you say damn sensitive Tetramminecopper(II) nitrate, often lazily and exasperately acronymised as TACN?

http://www.sciencemadness.org/talk/viewthread.php?tid=1778&a...

http://mihailru.freeservers.com/shopping_page.html

http://www.ab.ust.hk/hseo/sftywise/199302/page3.htm

Bad idea, even before we come upon the Al and nitrate dangers.
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[*] posted on 20-2-2010 at 12:04


I doubt that these compositions work.

Here is a simple way to test primaries,

Wrap a 1.5" square piece of Al foil around a 0.25" glass rod to form a tube.

Crimp over the bottom end.

Place about 250mg of the compound in the tube and pack
lightly with the glass rod. (avoid holding the tube in your hands for this step).

Insert a fuse and close the top.

Tape the little cracker on a block of pine, light the fuse and
get away.

Most "flash" mixtures will simply burn since the confinement
is not strong enough.

A primary like fulminate or HMTD will explode and the explosion will cut a deep grove (about 1" deep) into the
wood block.

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[*] posted on 21-2-2010 at 11:53



Quote: Originally posted by Blasty "Care to elaborate on which of these precipitated mixtures you've found particularly dangerous to deal with?"

Notes unavailable, another lifetime. Same procedure had been done once before on a smaller scale.
A solution of K2CrO4 dripped into a solution of Ba(NO3)2 with fine B suspended therein. Don't recall concentrations or T other than it was warm (preheated), w/ strong mechanical (overhead) stirring. Sometime after completion of rxn the 600mL beaker "exploded". The noise was like a very loud 'click' and nothing like the sound of glass that just fails thermally. The beaker broke into many small pieces, some being projected across a wide bench. Addition funnel did not break.
No light or flash was noticed. Stirrer had not touched the glass and rate was a nice vortex to a near the bottom of the vessel.
Nasty mess to clean-up and gave someone quite a scare.
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