Sciencemadness Discussion Board

TNT - chlorate composition

AndersHoveland - 15-9-2013 at 20:14

During the first world war, there were shortages of toluene, and there was research into other materials that could be mixed in to stretch the supply of TNT. A further consideration was that pure TNT was actually more brissant than was optimal for effectively producing shrapnel. Towards the end of the war, mixtures of chlorate and wax were used for fillings in hand grenades and landmines. In artillery shells, a small amount of wax was often mixed in to lessen the brisance of the TNT, for larger shrapnel size and maximum effectiveness.

There was another formulation that was proposed, though never implemented. It involved a mix of TNT, chlorate, and a small proportion of wax. The claimed advantage was greater effectiveness than simply diluting the TNT with wax, or lowering production costs while still maintaining good brissance. However, the advantages apparently were not considered significant enough for the added trouble, and it was not practical to melt it for filling into artillery shell. For mixing purposes, it was found more optimal to use lower melting point soft paraffins.

by weight, 4 parts TNT, 5 parts KClO3, 1 part soft paraffins

a somewhat stronger suggested formulation for artillery shells was given as
53 percent TNT, 43 percent KClO3, 4 percent wax

The small portion of paraffins apparently played two roles, substituting some of the TNT for maintaining an optimal oxygen balance, and lending more optimal physical qualities for preparation and pressing into shells.

Again, the claimed advantages of such compositions apparently did not warrant their use, since they were never used. And the role of chlorate as oxidizer in composition was later superseded by ammonium nitrate in formulations such as Ammonal. Ammonal did in fact see limited use in the first world war, however chlorate was more economical at the time (the Haber–Bosch process had only just recently come into operation).

It was claimed that these chlorate compositions were equal in power to pure TNT, if not more so. Obviously this does not mean that the detonation velocity was as high, but rather that the energy release was comparable, and that maximum brisance was not needed here.

Some patents refer to blasting agents containing mixtures of TNT with sodium perchlorate. However, the proportion of perchlorate in these formulations are always small (around 15 percent). This may possibly be due to the fact that perchlorate is more stable, so that using larger proportions are not really so effective for simple fuel-oxidizer explosives, despite the fact that it contains more oxygen. In other words, it is probably difficult to get the perchlorate to provide the detonation in a simple mechanical mixture, though a smaller amount can add power to one. Chlorate is more vulnerable to ignition, so it is practicable to get it to detonate with just wax in a simple fuel-oxidizer composition.

After the first world war, it appears chlorate compositions fell out of use, though they were still mentioned in explosives publications.

There are some other references to chlorate and paraffin wax charges where the wax is enhanced with other explosive additives. I do not think these are worth mentioning, and considering the small proportions, it is doubtful these enhancers increase performance enough to be worthwhile.

I will also just quickly mention the possibility of combining chlorate with nitrated polystyrene (styrofoam). The styrene would probably first have to be gelatinized with a solvent, and then dried after being mixed with the chlorate. This would be a simple to prepare cheddite-type composition, and could make an effective improvised blasting agent.

[Edited on 16-9-2013 by AndersHoveland]

Dany - 15-9-2013 at 21:09

Nice article AndersHoveland, combining oxidizer with high positive oxygen balance is a good idea to enhance negative oxygen balance explosive like TNT. I wish if you can provide some references for these information (fuel-oxidizer explosive compositions). choosing between chlorate and perchlorate i will choose the perchlorate. Sodium perchlorate is more dense than potassium chlorate (2.5 g/cm3 vs 2.34 g/cm3). perchlorate are better than chlorate when safety is an issue. also sodium perchlorate has a low melting point (130°C) compared to potassium chlorate (356°C) which make easier to melt the sodium perchlorate compositions, but it should be kept in mind that nothing is known about the thermal stability of sodium perchlorate-organic explosive (TNT) near the melting point of the composition. maybe an eutectic composition of sodium perchlorate and organic explosive is more desirable than just melt-casting a random perchlorate-organic species compositions.

for the nitrated styrene-chlorate composition i don't think that this composition is ideal for an improvised explosive since not everybody can access the styrene. what do you think about nitrated naphthalene-chlorate compositions? naphthalene is readily accessible and nitration is relatively fast (at least to mononitronaphthalene). for information on nitronaphthalene see Organic Chemistry of Explosives, Jai Prakash Agrawal, Robert Hodgson, pp 136-138.

Dany.

Ral123 - 15-9-2013 at 22:07

Maths shows adding Al is most likely to add more energy and brisance then oxidizers. No chlorate/perchlorate can be melt for practical reasons IMO. Yes sodium perchlorate will give potentially more energy density, but it's hygroscopic. Here's an idea:
Make OB mixture of KClO3/styrofoam. Then add acetone and form a nice cylinder. When the acetone evaporates, you'll have sensitive, low density cheditte block.

AndersHoveland - 15-9-2013 at 22:22

I would be very reluctant to try melting these compositions. Chlorate becomes a reactive oxidizer when even moderately heated. At the very least, I suspect heating it could pose a severe hazard, possibly even greatly sensitizing it such that a runaway combustion might lead to detonation, though not sure about that.
Quote: Originally posted by Dany  
perchlorate are better than chlorate when safety is an issue. also sodium perchlorate has a low melting point (130°C) compared to potassium chlorate (356°C) which make easier to melt the sodium perchlorate compositions, but it should be kept in mind that nothing is known about the thermal stability of sodium perchlorate-organic explosive (TNT) near the melting point of the composition.

You may be on to something.

With ammonium nitrate, it starts becoming a reactive oxidizer that spontaneously combusts with organic materials even before the temperature of decomposition. Sodium perchlorate might be more resistant hopefully. Would probably want to use an oil bath. Still not sure it would be a good idea to heat it to its melting point though, if all that is needed is to melt the TNT/wax. In fact, melting the sodium perchlorate (assuming it was safe) would probably not be a good idea because then it would just melt into a separate layer and may no longer be well mixed (unless perhaps if it was violently agitated and then quickly cooled).

Might do some research into how they mix the TNT into Ammonal.

Maybe this is the reason the these TNT-chlorate compositions were never considered practical, because it was too difficult to mix and pack into shells. Suggestion: gently heat just enough to soften it, and then pack it in. The TNT-paraffin mix would temporarily serve as a plasticizer, though shaping might still be difficult.
Quote: Originally posted by Dany  
combining oxidizer with high positive oxygen balance is a good idea to enhance negative oxygen balance explosive like TNT.

This certainly could be a plus, but I do not think they had this in mind, judging by the ratios of chlorate called for. Perhaps maintaining a fuel-rich ratio was still more optimal (there are many factors involved here). The chlorate, it seems, functioned mainly as a filler. Or maybe it would have been unworkable to mix and shape if too much chlorate were used. I suppose one could try higher ratios of chlorate, but I suspect the formation of CO is still more favorable than fully burning it off.

[Edited on 16-9-2013 by AndersHoveland]

Dany - 16-9-2013 at 00:43

Quote: Originally posted by Ral123  
Maths shows adding Al is most likely to add more energy and brisance then oxidizers. No chlorate/perchlorate can be melt for practical reasons IMO. Yes sodium perchlorate will give potentially more energy density, but it's hygroscopic. Here's an idea:
Make OB mixture of KClO3/styrofoam. Then add acetone and form a nice cylinder. When the acetone evaporates, you'll have sensitive, low density cheditte block.


The addition of aluminium do not increase detonation performance (Dcj and Pcj) but increase the blast effect. Experiment shows that aluminium powder decrease the detonation velocity and pressure because aluminium don't have the time to react in the detonation wave, so detonation wave will loose energy to compress the aluminium powder which in this case is supposed as an inert solid.
after the expansion of the detonation products the aluminium react with ambiant air or water if the explosive is detonated under water and generate more energy that is added to the firt blast (or increase the bubble energy for underwater detonation). as i mentionned in an earlier thread, the Gurney velocity of aluminium containing explosive is less than the pure explosive itself. for example the Gurney velocity of tritonal (80/20 TNT/Al) is 2.32 km/s while that of TNT is 2.44 km/s. the Gurney velocity is an important parameter fot metal acceleration application. Gurney velocity is usually measured in the cylinder expansion test at 19 mm or V/V0=7.

Value of Gurney energy can be found in LLNL Explosives Handbook:
Properties of Chemical Explosives and Explosive Simulants, B. M. Dobratz (Lawrence Livermore National Laboratory, University of California, 1985)

And Ral123, it is difficult to make a perfect zero OB composition of KClO3/styrofoam unless you know exactly the molecular mass of the polymer styrofoam which is not easily obtained or found. also you should pay attention to the density of the final chlorate/styrofoam composition. without any pressing low density explosive composition is obtained since styrofoam has already very low density, so performance will be very low.

Dany.





[Edited on 16-9-2013 by Dany]

SURT Tech. - 16-9-2013 at 03:07

http://yarchive.net/explosives/chlorate.html

"Chlorates and perchlorates are really a good raw materials for these
improvised stuffs. They can always be made to explode, if mixed with
combustible materials and if the oxygen balance of the mixture is near
zero (+- 50 %). The combustible material can be almost anything, wheat
flour, soja oil or toilet paper will do fine.

The "improvised plastic" seems to be quite the same I have used a long
time ago. I only had sodium chlorate, but it worked just fine. As a
fuel I had PVC or polystyrene dissolved in a plasticizer(phtalates,
sebacates) or if I didn't have any plasticizer, I took xylene as the
solvent. The finished product looked similar to C-4, but wasn't even
nearly as effective. It did make a large puff of smoke and a bang, but
it was almost ineffective on, for example, stone or steel. This stuff
had also the same drawbacks as the fertilizer mixtures: a minimal
charge, in this case about 0,5 kg. The mixture was also relatively hard
to ignite, I had to take a small booster charge, the blasting cap alone
was not enough, i.e. the mixture was actually too stable.

If perchlorates are used (potassium or ammonium), the explosive will be
a lot more brisant than with chlorates and safer, too. Still, the
detonation velocity is under 4500 meters/second, which is not enough
for unconfined charges. Hence, chlorates and perchlorates can
effectively be used for mining purposes only, not for demolitions.

"

Dany - 16-9-2013 at 03:30

SURT Tech.,

i think that the comment or copy-past paragraph has no meaning for me, since it is taken from a non-reliable references and it is written by an anonymous person.

first, he is saying that he make near zero oxygen balance composition with wheat flour, soja oil or toilet pape...how he know the exact molecular mass of these fuel so he can calculate OB? also i didn't understande what he mean by "near zero (+- 50 %)''???

secondly, he dissolved PVC or polystyrene in plasticizer! we all know that plasticizer are added in just few percent so to improve mechanical properties of the explosive composition. also, he didn't give any ratio of sodium chlorate/fuel so how he know that the mixture didn't detonate because it is very stable??? i think the material was so unreactive due to the diluation of the oxidizer or much of the solvent is still present.

finally, he conclude that adding perchlorate instead of chlorate will yield an explosive having detonation velocity less than 4500 m/s...how he know that??????

in conclusion: SURT Tech. forget about http://yarchive.net/explosives/chlorate.html. this site is written by anonymous people and give only unreliable informations...you must only trust book or published paper done by known researcher in the field.

Dany.

[Edited on 16-9-2013 by Dany]

AndersHoveland - 16-9-2013 at 03:44

Quote: Originally posted by Dany  
it is difficult to make a perfect zero OB composition of KClO3/styrofoam unless you know exactly the molecular mass of the polymer styrofoam which is not easily obtained or found.

For practical purposes, it has the empirical formula CH, so you can assume a molar mass of 13 g/mole for your calculations. The performance would probably be much better if the polystyrene was nitrated first. Detonation velocities are higher if the oxygen supply is intimately mixed at the molecular level, rather than just a mechanical mix.

Dany - 16-9-2013 at 04:45

in ANFO mixture the fuel oil is taken as CH but extrapolating this assumption to other organic material such as polymer like the one here may yield large error in calculating the oxygen balance. i do not recommend it.

Dany.

papaya - 16-9-2013 at 04:48

Quote: Originally posted by Dany  
in ANFO mixture the fuel oil is taken as CH but extrapolating this assumption to other organic material such as polymer like the one here may yield large error in calculating the oxygen balance. i do not recommend it.
Dany.


Then why not CH2, isn't this acceptable for long chain alkanes? Or fuel oil is mostly aromatic?

Dany - 16-9-2013 at 04:56

for me the approximation of CH or CH2 is probably correct for a fuel oil, but polymer like styrofoam, polystyrene...can have a very different molecular mass which will introduce large error in calculation if this approximation is used. I will accept an approximate molecular mass of the polymer for OB calculation. I will say use this approximation with GREAT CAUTION!

Dany.

SURT Tech. - 16-9-2013 at 05:29

The person who wrote this massage is not anonymous. His name is Arno Hahma. If you can’t recognize his old signature or don’t have a clue who is Arno, I think it’s better to study further in the professional and hobby energetic research field.

----------“how he know the exact molecular mass of these fuel so he can calculate OB?”

Would it be reasonable to say that he just knows? All this based on his experience and years’ work in the field. Read some more posts from him and will find what I mean.

----------“near zero (+- 50 %)”

I will like to speculate that this mean exactly what is meant. Near zero.

----------“secondly, he dissolved PVC or polystyrene in plasticizer!”

Yes, we all know the plasticizers are used in small quantities just to improve the mechanical properties of the finished explosive, but we also know that there are at least to plastic compositions, which bond the explosive crystals on the exact same principle.

The first is PVA – 4 (90% RDX, 8% PVA and 2% dibutyl phthalate). The second is
Perforex -79P ( PETN – 79%, dibutyl phthalate — 13%, nitrocelluse– 8%). Actually before years I have very good results with the last, substituting the PETN with ammonium perchlorate.

----------“he didn't give any ratio of sodium chlorate/fuel so how he know that the mixture didn't detonate because it is very stable???”

What ratio??? He just mixed the ingredients to form a plastic mass. The classic cheddite with wax is already fairly insensitive, so it’s close to mind what will be the properties of mixture with PVC or polystyrene + dibutyl phthalate. He also pointed that this is just an IMPROVISED crap. Some of this absolutely nonsense compositions, which we all do when we are bored or have huge brain fart. Is it fun.? YES. Is it practical? Not at all.

I posted the link and the info just to show that it’s absolutely impractical to make such compositions, especially those based on polystyrene.

----------“finally, he conclude that adding perchlorate instead of chlorate will yield an explosive having detonation velocity less than 4500 m/s...how he know that??????”

May I assume that this statement is based on some of the properties of the classic cheddite compositions based on perchlorates and the fact that he use INERT binder mass?

----------in coclusion: SURT Tech. forget about http://yarchive.net/explosives/chlorate.html. this site is written by anonymous people and give only unreliable informations...you must only trust book or published paper done by known researcher in the field.

In conclusion. It’s not very wise to make such a great statements, when the post of Arno Hahma WAS actually full of useful information. Beside http://yarchive.net/explosives was the first and the last place were someone can find some useful information or make some useful conversation with REAL specialist in the field. Some of the old school members here knows exactly what I’m talking about.

AndersHoveland - 16-9-2013 at 06:44

Quote: Originally posted by Dany  
for me the approximation of CH or CH2 is probably correct for a fuel oil, but polymer like styrofoam, polystyrene...can have a very different molecular mass

The empirical formula for fuel oil is extremely close to CH2, since it is composed almost entirely of medium chain alkanes. The empirical formula for polystyrene is CH. Polystyrene is formed from styrene, which has a very well defined molecular formula, C8H8. Thus the polymer will also have a very well defined 1:1 ratio of hydrogen to carbon.
Quote: Originally posted by papaya  
Then why not CH2, isn't this acceptable for long chain alkanes? Or fuel oil is mostly aromatic?

Fuel oil contains a mix of medium chain alkanes, ranging from C10-C18, depending on the type of oil. Some petroleum distillates do contain a small fraction of aromatics, but this is usually mostly removed because they are now recognized as potential carcinogens. The empirical formula for wax can also be approximated as CH2, for the purposes of combustion calculations.

[Edited on 16-9-2013 by AndersHoveland]

Dany - 16-9-2013 at 07:16

Yes your reply prove that you are a real amateur.

first, every professional scientist need to put references of what he is talking about even if the work is realised by him/his group.

"What ratio??? He just mixed the ingredients to form a plastic mass..." Yeah, you must remember that we are discussing scientific topic and not kitchen recipes. Even in kitchen recipes they give approximate proportion of ingredient...

"Would it be reasonable to say that he just knows? All this based on his experience and years’ work in the field...Yes this what you are telling me, or what you feel...so please if you or your hahma knows the "near oxygen balance" of chlorate/perchlorate-paper toilet/wheat flour composition i'll be glad to take the ratio so i can made this explosive myself (remember calculation are needed with references).

"The classic cheddite with wax is already fairly insensitive, so it’s close to mind what will be the properties of mixture with PVC or polystyrene + dibutyl phthalate"...more and more of your feeling with no scientific prove. extrapolating properties of a material like wax (a non polymer material) to other material like polystyrene or PVC (polymer compound) can induce large error in estimating sensitivity and lead to erroneous conclusion. Remember sensitivity is a complexe feature of an HEDM and depend on many factors. Physical factors like granulometrie, porosity, liquid or solid etc...or chemical factors like the presence of certain explosophoric group or bonding type like hydrogen bond (for more information on sensitivity see properties of chemical explosives and explosive simulants, Dobratz, B.M., 1972).

"May I assume that this statement is based on some of the properties of the classic cheddite compositions based on perchlorates and the fact that he use INERT binder mass?"...yes and i'll assume that all HMX based explosive have detonation speed over 8.5 km/s which is nonsense. predicting detonation speed based on another similar composition is a big mistake, since density can vary from composition to another and the detonation products are not the same so detonation speed or pressure will vary...read "Detonation:Theory and Experiment'' for Wildon Fickett, William C. Davis and "numerical modeling of explosive and propellant" for one of the gratest explosive scientist CHARLES MADER. read these references and don't assume!

"The "improvised plastic" seems to be quite the same I have used a long time ago. I only had sodium chlorate, but it worked just fine. As a fuel I had PVC or polystyrene dissolved in a plasticizer(phtalates, sebacates) or if I didn't have any plasticizer, I took xylene as the solvent"....now we are confused...plasticizer or solvent? our friend hahma based on experience and years’ work in the field isn't able to distinguish between solvent and plastisizer...for hahma xylene phtalates and sebacates are indistinguishable.

A small advice: when posting another time try to show us some good references rather than talking about your assuming and feeling...the net is full of sites on poetry and kitchen recipes where you can tell them your feeling.

Dany.




















[Edited on 16-9-2013 by Dany]

SURT Tech. - 16-9-2013 at 07:40

Quote: Originally posted by Dany  

A small advice: when posting another time try to show us some good references rather than talking about your assuming and feeling...the net is full of sites on poetry and kitchen recipes where you can tell them you feeling.

Dany.


[Edited on 16-9-2013 by Dany]


No problem Dany. I will just stop posting. It’s not a big deal for me anyway.

Dany - 16-9-2013 at 07:43

"It’s not a big deal for me anyway"

same to me.

Dany.

AndersHoveland - 16-9-2013 at 08:38

Quote: Originally posted by Ral123  
Maths shows adding Al is most likely to add more energy and brisance than oxidizers.

Some pyro enthusiasts seem to be proponents of adding Al metal powder to everything.

You may indeed be correct, adding Al would increase energy more, but only up to a small percentage. TNT is already very fuel rich, adding Al is certainly not helping the oxygen balance. Brisance is a complicated thing. A little Al may be able to slightly increase brisance in some circumstances, but not here. Although the formation of bonds between Al and O is very energetic, in terms of reaction rates metal powders take significantly longer than everything else in the composition to 'burn off'.

I also question the chemical compatibility safety of mixing chlorate with metal powders and storage of such compositions.

[Edited on 16-9-2013 by AndersHoveland]

Dany - 16-9-2013 at 08:55

"I also question the chemical compatibility safety of mixing chlorate with metal powders and storage of such compositions"

from [1]:

Combustion of low-exothermic condensed systems is widely used for emergency oxygen generation in aircraft, spacecraft, submarines, and mine rescue. Oxygen in such systems is produced typically by decomposition of metal (e.g., Li, Na, K) chlorates or perchlorates. After initiation at one end of the chlorate-based “candle,” the reaction front travels in a self-sustained manner toward the other end, generating oxygen according to the flow requirements [cf. 3]. A characteristic of chlorate/perchlorate decompositions is that they are exothermic. However, because their exothermicity is not sufficiently high to maintain reaction self-propagation, the initial reactant composition includes some amount of metal fuel (e.g., Fe, Al, Co, Sn). Oxidation of the metal by a portion of the produced oxygen liberates additional heat, which ensures the combustion front propagation. The reactant mixture usually also includes a transition-metal oxide as a decomposition catalyst, as well as an alkaline compound which traps traces of chlorine 4 and 5.

The combustion temperature in such systems is generally in the range 300 to 800°C, and the reaction front velocities are 0.01 to 0.1 mm/s

Note that such relatively low temperatures and velocities distinguish these systems from well-studied rocket propellants and other high-energetic compositions containing chlorates (or perchlorates) and large metal fuel loadings. Combustion phenomena in low-exothermic condensed systems are not well understood and, for this reason, it is difficult to control the processes. One of the complications is that the combustion process in such systems is often characterized by unsteady phenomena (e.g., auto-oscillations or spin [cf. 6, 7 and 8]). The other is related to the complex mechanism of heat transport in heterogeneous porous media [cf. 9 and 10]. In most condensed systems, the combustion wave propagates owing to heat transfer by thermal conduction through the solid skeleton of the reaction mixture. However, the systems used for oxygen generation are characterized by such low exothermicity that combustion is possible only if the unreacted mixture ahead of the front is additionally preheated by the flow of hot product gas

according to this study, low metal loading in chlorate composition are safe for storage since they are used in many practical area.even this composition need a transition metal oxide catalyst (Co3O4) which promotes decomposition of the chlorate

in this study NaClO4/Sn is used with Sn<10wt.%

reference:

[1] Mechanism of Combustion in Low-Exothermic Mixtures of Sodium Chlorate and Metal Fuel, E Shafirovicha,
A.S Mukasyana, A Varma, G Kshirsagarb,Y Zhangb, J.C Cannonb, Volume 128, Issues 1–2, January 2002, Pages 133–144.

[Edited on 16-9-2013 by Dany]

AndersHoveland - 16-9-2013 at 09:42

And yet flash powder can have potential friction sensitivity, and static electricity hazard. Caution should be used if one is not entirely sure.

Also important to mention, chlorate is not compatible with ammonium salts. This creates a severe safety hazard for long term storage.

[Edited on 16-9-2013 by AndersHoveland]

Ral123 - 16-9-2013 at 10:31

We can purify and make stable, predictable product in lab, but adding aluminium will cause great uncertainty to the material. You don't know the exact particle size and purity. The stability and/or performance may be compromised. I don't know how Al interacts with the materials and their decomposition products so I don't do many tests with Al. But I can assure you, HMTD/Al(stupidity here) is much more energetic then HMTD. Al helps where energy is low, not where oxygen is in excess.

AndersHoveland - 16-9-2013 at 11:02

Quote: Originally posted by Ral123  
But I can assure you, HMTD/Al(stupidity here) is much more energetic then HMTD. Al helps where energy is low, not where oxygen is in excess.

Interesting line of thinking. However, I think the heat of explosion from HMTD is rather low, oxidation is mostly through a radical mechanism, not combustion, and any Al that gets oxidized would be reacting with already reduced oxygen atoms. In fact, I do not see how the temperature could reach a level sufficient for the Al to combust here, unless perhaps abiotic heating from the shockwave.

Honestly, I am not really sure, just something to think about.

Ral123 - 16-9-2013 at 14:42

Let's say if want to double the energy of 100g ETN, you need to add 70g Al, witch leaves you with 170g. To double the energy of 100g HMTD you need to add 40g Al(there isn't oxygen for more) witch leaves you with 140g material. Adding Al to low energy materials is with more pronounced effect. And yes, deflagrating AP/HMTD gives enough heat to ignite the Al, it's similar to flash actually.

caterpillar - 17-9-2013 at 01:44

Quote: Originally posted by Dany  
what do you think about nitrated naphthalene-chlorate compositions? naphthalene is readily accessible and nitration is relatively fast (at least to mononitronaphthalene). for information on nitronaphthalene see Organic Chemistry of Explosives, Jai Prakash Agrawal, Robert Hodgson, pp 136-138.

Dany.


For us, poor amateurs, DNT with KClO3 may have some interest. Di or trinitronaphtalene as well. These compounds can be easily prepared- no oleum, nor hi temperature. Once I made nitronaphtalene (or dinitro, I cannot be sure), but I mixed it with AN.

AndersHoveland - 30-9-2013 at 19:35

It is not a very good oxidizer for explosives, but NaNO3 can also be used in some instances.
Quote:
Investigations during the past year by John Swenehart, in cooperation with the Bureau of Public Roads of the United States Department of Agriculture, have evolved a new explosive mixture composed of 45 parts of TNT and 55 parts of sodium nitrate. This mixture, known as Sodatol…

Wisconsin used over 2,000,000 pounds of sodatol this last season.
Picture of large shattered rock, with caption: Sodatol has shattering power to crack the big ones. When breaking stones this way, workers should keep out of range of flying fragments.

Sodatol is about 15 to 20 per cent stronger than ordinary dynamite and has a shattering strength approximately equivalent to 40 per cent ammonia dynamite. Nitrate of soda, one of the ingredients used in making sodatol, absorbs water readily, but in a mixture with TNT in properly parafined cartridges the moisture encountered in agricultural work does not interfere with its use. Small quantities of water prevent explosion and cannot be readily removed. It is essential that it be kept dry at all times, which is unlike the requirements for handling dynamite or picric acid.
Sodatol is not highly inflammable and burns slowly without explosion in small quantities. It is not sensitive to moderate shocks and hauling, which makes it safe to use for all ordinary purposes. Since the material is slower than picric acid and relatively more insensitive, it is less efficient for mud-capping of rocks or ditch blasting.
Results of various tests indicate that sodatol is a satisfactory explosive for all general work. It stands storage without deterioration… A large detonator such as the No. 6 blasting cap or an electric blasting cap should be used in detonating sodatol.

University of Wisconsin, “The Year’s Progress of the Experiment Station”, 1914, H.L. Russel

Although it must certainly result in a lower detonation velocity than ammonium nitrate, it does have the slight advantage of greater oxygen balance, to burn off the TNT. Again, nitrate of soda is a poor oxidizer to use, so the large proportion of TNT is essential. In other words, it is simply not possible to detonate a mixture of NaNO3 with wax.

Ral123 - 30-9-2013 at 23:02

The only purpose of KNO3/TNT I see is that it's cheaper then TNT, less hygroscopic then TNT/AN and less brisant, making it a choice for defensive hand nades. Also the metal confinement will make detonation of mixtures with larger portion of KNO3 possible. However I lack the imagination, what booster can set off cast KNO3/TNT 50/50.

AndersHoveland - 1-10-2013 at 00:01

Do not forget, this was before the Haber process. Most of that NaNO3 likely came from fossilized bird excrement in Chile ("Chile saltpetre"), or the more recent Birkeland–Eyde process, by passing air through an electric arc and neutralizing the nitrogen oxides with solution of soda.

Again, NaNO3 is a really terrible oxidizer. Yes, KNO3 is the main ingredient in Black powder, but only because it has been finely crystalized throughout the powder. Ever tried just burning black powder that has not been pre-soaked and dried? No matter how finely ground and well-mixed, it only burns and flares, and very difficult to get to burn in small quantities. So KNO3 may be suitable for pyrotechnic compositions, but for actual detonation, that is a different matter. Detonation proceeds best when the fuel and oxidizer are mixed on a molecular level, rather than a simple mix of two separate solid phases. For a composition of Sodatol, the detonation velocity must really suffer, in fact it is probably not much more than if one mixed TNT with an inert powder. Yet it will contribute oxygen to help burn off some of the TNT, even if the decomposition of NaNO3 is not very energetic.

The only reason it was used is that NaNO3 was cheap.

caterpillar - 1-10-2013 at 05:06

Quote: Originally posted by AndersHoveland  

Yes, KNO3 is the main ingredient in Black powder, but only because it has been finely crystalized throughout the powder.


Not true. NaNO3 is hygroscopic, this is the main reason, why KNO3 is used in BP.

Ral123 - 1-10-2013 at 05:33

I think the lower density of the KNO3 somewhat contributes to the flame speed. I think the very low hygroscopicity is a must for a serious application.

caterpillar - 1-10-2013 at 14:04

AN is hygroscopic, but it is widely used in serious application. But powder and explosive are different things and there are different requirements for them. BP must be dry, but pressed NC must be slightly wet. Generally, some amount of water in explosive often increases its performance.

DubaiAmateurRocketry - 2-10-2013 at 10:39

Quote: Originally posted by Dany  
choosing between chlorate and perchlorate i will choose the perchlorate. Sodium perchlorate is more dense than potassium chlorate (2.5 g/cm3 vs 2.34 g/cm3). perchlorate are better than chlorate when safety is an issue. also sodium perchlorate has a low melting point (130°C) compared to potassium chlorate (356°C) which make easier to melt the sodium perchlorate compositions
Dany.

-Dany

Would like just to correct a small mistake that Potassium perchlorate is denser,
KClO4 Have a density of 2.524
NaClO4 Have a density of 2.499

NaClO4 Have a melting point of 468 degree celsius, rather than the 130 you mentioned.

The 130 is for the hydrated sodium perchlorate, which is rather very inefficient compared to anhydrous.

Fantasma4500 - 3-10-2013 at 07:42

infact xClO3 with vaseline (petroleum jelly) is used under the name 'Cheddite C' its very often used by amateur uncertified demolitions experts, to put it profesionally..
also xClO3 and sugar is used, it have been described as 'white powder' in a seemingly old scanned book on field manufactured explosives i have laying around.. this composition does go off when hammered throughly, sensitivity increased alot if a percentage of aluminium powder is added, oxides would probably do the same, perhaps both.. yes?

i recall having seen HDN mixed with KClO4, to improve the energy release and OB, i cant get data on this as the guy sadly went totally and entirely gone all of a sudden.. i recall something around 80 20 HDN KClO4
he did not get to show any comparative tests but only a 20g charge being setoff with no targets or anything, but he said by his experience he could feel there was a greater energy release

Ral123 - 3-10-2013 at 08:19

I despise hygroscopic energetics. Why would you use expensive KClO4 with HDN, to make one? Why ruin KClO3 with sugar? HDN is good party with AN. KClO3 with wax. KClO3, KClO4, KNO3 is good party with TNT, AN is good party with hydrazine.

killswitch - 3-10-2013 at 15:11

What about TNT/NH4ClO4?

caterpillar - 4-10-2013 at 04:19

Quote: Originally posted by killswitch  
What about TNT/NH4ClO4?

For some reasons, NH4ClO4 is not used in explosive compositions as widely, as AN. I met one such composition (I do not remember proportions): NH4ClO4, RDX, Al and small amount of paraffin. It was designed special for blusting hard rocks.

killswitch - 4-10-2013 at 05:00

Quote: Originally posted by caterpillar  
Quote: Originally posted by killswitch  
What about TNT/NH4ClO4?

For some reasons, NH4ClO4 is not used in explosive compositions as widely, as AN. I met one such composition (I do not remember proportions): NH4ClO4, RDX, Al and small amount of paraffin. It was designed special for blusting hard rocks.


Might have something to do with the poisonous fumes given off.

Ral123 - 4-10-2013 at 07:34

NH4ClO4 mixtures would have good energy density, specially with Al added, but brisance suffers heavily. NH4ClO4 has lower velocity on it's own then AN. So who needs this expensive, chemically aggressive mixture witch is outperformed by high power blast jelly anyway.

AndersHoveland - 4-10-2013 at 09:07

Just to mention again, it might not be possible to get sodium/potassium perchlorate mixtures to detonate, or at least it may likely be much more difficult than the chlorate. Although perchlorate contains more oxygen, it is also more stable and less reactive chemically.

Normally simple fuel-oxidizer mixtures cannot be detonated (at least solid mixtures), but chlorate is somewhat of an exception to this because it gives up its oxygen so easily. Nevertheless, the detonation velocity of chlorate-wax compositions is still very low. In fact, besides the use as a cheap filler to create shrapnel, I doubt it has any practical use at all. Probably not much more effective than Black powder. The KClO3 and fuel are in separate mechanical phases, not part of the same molecule, and KClO3 cannot decompose by itself, so that greatly limits the reaction rate.

Whether the oxidizer is incorporated into the actual crystal structure on a molecular level makes a big difference. So combine the fact that the perchlorate oxidizer is in a separate phase (the sodium or potassium salt) and the fact that it has a higher decomposition temperature and is not quite as reactive in fast combustion, and it may be that a simple mixture with wax is not sufficient to propagate detonation, like it is with chlorate.

This is why it may take a much higher ratio of TNT in the composition if sodium perchlorate was used, making perchlorate more of an additive, rather than a main component.

Again, this only applies to Na or K perchlorate mixes one is trying to get to actually detonate. For simply pyrotechnic uses, even flash powder, potassium perchlorate works quite well.

[Edited on 4-10-2013 by AndersHoveland]

caterpillar - 4-10-2013 at 14:22

Quote: Originally posted by AndersHoveland  

The KClO3 and fuel are in separate mechanical phases, not part of the same molecule, and KClO3 cannot decompose by itself, so that greatly limits the reaction rate.
[Edited on 4-10-2013 by AndersHoveland]


Small correction- KClO3 is an endothermic compound and therefore it can decompose by itself- even pure KClO3 can explode. Situation is just opposite with KClO4- this one is an exothermic compound and can explode no more than NaCl. But mixtures with KClO3 are much more sensitive than mixtures, based on AN. KClO4 on the other hand is more expensive than AN and produces smaller volume of gases. This is why mixtures with KClO3 have some interest only for us, poor amateurs- there is a simple route to aforementioned oxidizer ( Ca(ClO)2 -> Ca(ClO3)2 -> KClO3 ).