Sciencemadness Discussion Board

SHN experiences

needle - 1-6-2004 at 08:05

Hello.
Does anyone have valueable experiences in the making,useing and storing of SNH, sorbitol hexanitrate? I have not been able to find much of anything, VOD, lead-block-test, brisance, sencitivity, etc.

What will give you the highest yield? H2SO4 + xNO3, or HNO3 ? (my HNO3 is 62%)
I would really like to start a discussion about SHN, because it for me, and maybe others, would be the economic alternative to MHN, since mannitol is much more expencive than sorbitol.

Regards.

vulture - 1-6-2004 at 11:27

Thread moved - Please post in the appropriate section.

Furthermore, this thread is borderline.
SHN isn't exactly exotic, but it's rare and that's why I'm going to allow it.

However, only discussion pertaining to it's chemistry is allowed. No practical discussion about charge sizes, detonators, etc...

Ium - 1-6-2004 at 19:20

To quote COPAE:
Quote:

Nitrosorbite (Sorbitol hexanitrate)
d-Sorbite occurs in the berries of the mountain ash, but is more
readily procured by the electrolytic reduction of d-glucose. It
crystallizes with one molecule of water in small crystals which
lose their water when heated and melt at about 110°. Nitrosorbite,
isomeric with nitromannite, exists as a viscous liquid and
has never been obtained in the crystalline state. It is used in nonfreezing
dynamites.


A trend that exists with most nitrated sugars is that they are inherantly unstable unless pure and readily evolve oxides of nitrogen upon mild heating(50*C and up). Do not expect to always get a crystalline precipitate either. Most of the nitrated sugars have low melting points and in the liquid state are very hard to fully relieve of acid contaminants. The only more elusive sugars that have had tolerable properties are the nitrated forms of the polyols mannitol and erythritol.

Hystrix - 7-6-2004 at 22:33

Quote:
Originally posted by Ium
To quote COPAE:
Nitrosorbite, isomeric with nitromannite, exists as a viscous liquid and has never been obtained in the crystalline state. It is used in nonfreezing dynamites.


The stuff described by Davis is not pure SHN but its mixture with pentanitrate. According to Urbanski, pure SHN melts at 55 deg.C. and has the same power like MHN. For making it 1 part of sorbitol should be dissolved in 5 parts of fuming NA at 0 deg. C. and then poured to 10 parts of oleum.
I have attempted several times to make SHN with AN and sulfuric acid but results were not satisfactory for me.

Phantom - 21-12-2011 at 15:58

What I read, the VoD is around 8000m/s.
Sorry, I don't know the exact source for that.

AndersHoveland - 21-12-2011 at 16:13

Sorbitol is just a stereoisomer of manitol, meaning they have the same molecular formula and structure, just a slightly different shape. The density of manitol, for example, is only 0.03 g/cm3 more than sorbitol.

Their explosive properties should be nearly the same.
Mannitol hexanitrate typically has a density between 1.230-1.604 g/cm3, and a detonation velocity of around 7km/sec.
But one source states that the detonation velocity is 8260 m/s at a density of 1.73 g/cm3 when confined.

I also found this:
Quote:

Is there a chance to nitrate Sorbit (a hexa alcohol, cheaply available as a replacement sugar for diabetics) into a kind of hexanitrate ?

Yes, it is possible and has been done. However, sorbitolhexanitrate is not easy to make. To nitrate sorbitol to the hexanitrate one requires very concentrated nitric acid, that has to be absolutely free of nitrites. Still, the product tends to be impure, i.e. contain much of the pentanitrate. If so, the product will be a wet mass of crystals, as the mixture of hexa- and pentanitrates melts relatively low. That makes the purification particularly difficult. Also, the pentanitrate is not as stable as the hexanitrate. That is one reason, why sorbitolhexanitrate is not very stable, but easily starts giving off
red fumes on storage. The compound is also very sensitive to shock and friction, about as sensitive as nitroglycerine.

A better choice is to nitrate mannitol, an isomer of sorbitol. Mannitolhexanitrate is much easier to make, it crystallises nicely and is easily purified by recrystallization from acetone. MHN is much more stable than sorbitol hexanitrate, but it still requires a stabilisator, such as akardites or centralites for prolonged, safe storage.

MHN is very sensitive as well, although not as much as the sorbitol derivative. MHN has been used as the base charge for blasting caps, as it is very easy to ignite even with such a weak initiator as tetracene. I would still prefer using PETN for caps, though.

: stated above, this may be (if somewhat stable) an incredible bristant : explosive... Its an idea from my school time, but i never tried

You are right, sorbitol and mannitol hexanitrates are extremely
powerful explosives, more powerful than PETN or RDX. I can't remember the detonation velocity exactly, but it is in the order of 8500 m/s. The heat of explosion is more than that of the two explosives mentioned above.

MHN and SHN are not something you want to do in your kitchen. Both of the explosives are close to the primary explosives in their properties. In addition, you need really concentrated acids in large excess to gain any yield and such acids might do some severe damage to average kitchen furniture. Nitration with 99,5+% nitric acid evolves
incredible amounts of nitric acid fumes.


Note that "tetracene" formerly referred to the explosive that is now referred to as tetrazene.
Quote:

Tetrazene
VOD: 1500 to more than 4000 m/s (depending on how it is initiated)
Density: 1.7 g/cm3.
Lead block test: 155cm3 /10g.
Structure: (HN4C)--N=N--N(NH2)--C(=NH)NH2 * H2O

Tetrazene is slightly more impact-sensitive than mercury fulminate. In contact with fire, it readily explodes, producing large amounts of black smoke. Nitrate and perchlorate salts of tetrazene are much more powerful. A mixture of tetracene and mannitol hexanitrate ( in a 4/6 ratio) will give a powerful brisant primary that detonates from moderate heat.

Tetrazene is a colorless pale yellow, fluffy material with slight hygroscopic properties.
It is almost insoluble in water, alcohol, ether, and benzene.
It is stable at normal temperatures when wet or dry, but decomposes in boiling water. Tetrazene is sensitive to friction, shock, and flame. Its brissance is maximized when it has not been compacted; when pressed enough, its sensitivity is reduced or destroyed, which is known as dead pressing. Tetrazene is not suited for blasting caps or alone as an explosive since it does not detonate itself very efficiently. It is best suited for booster charges or in blasting caps mixed with other explosives. It should be detonated by another explosive charge, otherwise if just ignited, it will undergo a lower velocity detonation.

It is prepared by reacting sodium nitrite with an aminoguanidine salt dissolved in acetic acid at 30–40 °C.

Preparation:
Prepare a solution of 34 g of aminoguanidine bicarbonate and 12.5 mL of glacial acetic acid with 2500 mL of water in a 3-liter Florence flask. Gently warm the flask on a steam bath and shake periodically until everything is completely dissolved into solution. The solution should be filtered to remove any impurities that may have not dissolved, then cooled to 30º C by running cold water from the faucet over the flask. It is necessary to filter the solution if there are impurities present. Add 27.6 g of sodium nitrite to the solution while swirling to dissolve it. Set the flask aside at room temperature for 3 or 4 hours then shake it vigorously to start precipitation of the product. Let the flask stand for another 20 hours. After standing, decant as much of the solution off as possible and drown the remaining crystals with water. Decant and drown with water several more times to wash the crystals. Filter the washed crystals to collect them and thoroughly wash again with water. Dry the product at room temperature and store in a sealed glass container to keep out the moisture.


(aminoguanidine can be obtained from the reduction of nitroguanidine with HCl/Zn, or by reacting hydrazine hydrate with guanidine)

[Edited on 22-12-2011 by AndersHoveland]

Rosco Bodine - 21-12-2011 at 19:24

Quote:
MHN is much more stable than sorbitol hexanitrate, but it still requires a stabilisator, such as akardites or centralites for prolonged, safe storage.


@AndersHoveland, Where exactly did you find the above? Is there published data on stability tests to confirm this ? Or is it only somebody's guess that because a particular stabilizer works with cordite then logically? it must? somehow also work as well for anything else .....which is an incorrect assumption. Stabilizers are application specific to some extent, and are not necessarily transferable.

AndersHoveland - 21-12-2011 at 19:56

http://yarchive.net/explosives/mannitol_hexanitrate.html
Quote:
MHN is much more stable than sorbitol hexanitrate, but it still requires a stabilisator, such as akardites or centralites for prolonged, safe storage.


Yes, obviously this is suspect, and I am hesitant to believe it.
Sorry, I did not read all of the post. I would not have copied this part if I had seen it.

Rosco Bodine - 21-12-2011 at 20:14

No problem, I have looked into this a little bit, enough to know that stabilizer of choice is a pretty specific scenario and probably worsened by low stability for the candidate for stabilization. The specificity probably relates to intermediate decomposition products being different so what opposes the equlibrium in one case may not be the same as another. Even odd materials not generally thought to be a stabilizer can stabilize in a specific case. There are even situations where one energetic material stabilizes another so a blend of the two has a synergistic stability.

http://www.sciencemadness.org/talk/viewthread.php?tid=12623#...

http://www.sciencemadness.org/talk/viewthread.php?tid=16759#...

On a historical note Sobrero at first noted that nitromannite was perfectly stable, until I think it was a stored sample spontaneously detonated without provocation and destroyed part of his laboratory. Then it was learned that
all it takes is light to induce decomposition ...the stuff is photosensitive .....just like highly concentrated nitric acid is photosensitive....and light exposure is all it takes to start the autocatalytic decomposition of nitromannite.

No tanning bed for your MHN. Possibly, if there is a chemically compatible sort of "sun block" material which could coat the precipitating crystals, that might preempt
the photosensitivity as a kind of "first barrier stabilizer"
which could be in part how cyanoguanidine may work.
The mechanism is probably chemical there, but it may have a dual aspect, I'm not sure.

[Edited on 22-12-2011 by Rosco Bodine]

AndersHoveland - 21-12-2011 at 20:56

I would think that any substance which can absorb traces of NO2 that form, and which are miscible with or completely absorbed into, would act as a stabilizer to nitrate esters. If I remember correctly, substances such as ethylene diamine or aniline will act as stabilizers. For example, small quantitiies of diphenylamine are sometimes added to smokeless propellants.
http://www.islandgroup.com/military/propellant_stabilizers.p...

Also, if the nitrate ester is aborbed into nitrated cellulose, this will also greatly reduce sensitivity. In the case of a solid nitrate ester, it could be leached into the cellulose with acetone.

[Edited on 22-12-2011 by AndersHoveland]

Rosco Bodine - 21-12-2011 at 21:14

You are welcome to operate on the assumption that the reality of what occurs in actuality is whatever you think or speculate, hypothesize or theorize. There is a more than subtle difference between "may in some cases act as stabilizers" as compared with your more absolute idea of materials that "will act as stabilizers".
There isn't a one size fits all scenario for stabilizers, it is not so general.

freedompyro - 23-12-2011 at 01:40

My notes say that the addition of 5-10% K or Na Salicylate's stabilize MHN for storage. I seem to have lost the source of that information... That should give you guys a lead.

[Edited on 23-12-2011 by freedompyro]

Dany - 6-9-2013 at 04:33

Quote: Originally posted by AndersHoveland  
http://yarchive.net/explosives/mannitol_hexanitrate.html

Quote:
MHN is much more stable than sorbitol hexanitrate, but it still requires a stabilisator, such as akardites or centralites for prolonged, safe storage.


Yes, obviously this is suspect, and I am hesitant to believe it.
Sorry, I did not read all of the post. I would not have copied this part if I had seen it.


Unfortunately, the reference given in your reply give some wrong believes. According to a new study on the thermal stability of nitrate ester MHN is less thermally stable than SHN based on the critical temperature of thermal decomposition (measured by non-isothermal thermogravimetry). The critical temperature of MHN is 138.5 °C while that of SHN is 160.9 °C. the detonation velocity of SHN @ 1.78 g/cm3 is 8.23 km/s and that of MHN @ 1.59 g/cm3 is 9.01 km/s. although the Dcj of MHN seems very high for a 1.59 g/cm3 density, this is what the kamlet-jacobs semi-empirical methods predicts. for more information on thermal stability of nitric ester see the attached file.

Dany.



Attachment: thermal stability-nitric esters.pdf (1.3MB)
This file has been downloaded 1742 times



[Edited on 6-9-2013 by Dany]

Rosco Bodine - 6-9-2013 at 08:30

US2616920 is of interest for dicyandiamide or cyanoguanidine being reported and pateneted as tested useful as an effective storage stabilizer for nitomannite. Betaine is another candidate as a stabilizer.

http://www.sciencemadness.org/talk/viewthread.php?tid=12623&...

Attached is the dicyandiamide related patent US2616920


[Edited on 6-9-2013 by Rosco Bodine]

Attachment: US2616920_Dicyandiamide_Stabilized_Nitromannite.pdf (191kB)
This file has been downloaded 921 times