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Author: Subject: Diving Into the World of Fulminates
Hennig Brand
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[*] posted on 25-5-2010 at 18:15


http://pubs.acs.org/doi/abs/10.1021/ja02259a034
This is where I found an article, which shows the incredible stability of silver fulminate if article can be trusted. The sample of SF was over 40 years old, not stored completely out of light, and when tested tested practically identical to a fresh sample both in performance and chemically.(note: sample was stored under water however, this is good practice anyway for safeties sake)

This patent talks a lot about desensitizing SF, mostly the ammonia method used with the throw down/bang snaps during manufacture, and sometimes shipping. It does give some other examples as well. I apologize if this has all ready been posted, it seems like the kind of thing that would be.
http://www.freepatentsonline.com/4270435.html

Maybe someone can help me out, what I stated as the explosion temperature a couple posts up, for some reason I was thinking that was the decomp temp. Does anyone know what the decomp temp for Silver fulminate is? I know I have put small amounts on a fairly hot wood stove and been frustrated by no bang.

Didn't notice this before, Wikipedia says autoignition happens at 170C, for silver fulminate.


[Edited on 26-5-2010 by Hennig Brand]
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[*] posted on 30-5-2010 at 05:14


Sorry for double posting, but I have something to report, I'll make it quick.
I tried a few more batches since the last one I posted and have gotten my yield up to around 0.75g Silver Fulminate per gram of silver used.
At least for me, with the materials I am using the decomp temperature is actually much below 80C. On one of my partly unsuccessful runs I noticed a very large precipitate but within 2 seconds the temperature rose 5 or 10C and the precipitate vanished. Silver fulminate seems to form almost instantly and can vanish just as quickly if temperature is not very closely controlled.
The next batch I was very determined to capture this large yeild, and by being super vigilant with temperature I did get most of it I think(0.83g from 1.1g silver). I kept the reaction down below 70C almost the whole time, it jumped over for a second at the start of the reaction. It was hard keeping it cool. I think large batches would be next to impossible to control.
Liebig claimed to get about a gram from a gram of silver, and I am now starting to see that I probably can to. Liebig was apparently a real expert when it came to silver fulminate.

Silver Fulminate seems so much more difficult than mercury fulminate to synthesis properly, am I just going about it wrong?
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[*] posted on 27-1-2011 at 11:17


Sorry to bring up an old thread, but this one seemed the most suitable for the question that I have.

Could perhaps the HNO3 made from Ca(NO3)2 and H2SO4 be used to make mercury fulminate?

I was thinking to first mix Ca(NO3)2 with H2SO4 to make the HNO3. If the H2SO4 is detrimental to the fulminate-forming reaction, an excess of Ca(NO3)2 would be added to the H2SO4 to use it all up. The result would be a thick suspension of CaSO4 and HNO3 (with the excess Ca(NO3)2), to wich a correct amount of water would be added to dilute the HNO3 to 50-60%. Then the mix would be filtered, or left to stand for some time so that the CaSO4 settles and the HNO3 can be decanted.
The HNO3 made this way would contain some dissolved CaSO4 (dont know how much of it dissolves in 50-60% HNO3) and Ca(NO3)2 or H2SO4 (depending on which of the two was in excess).
I dont think that some Ca(NO3)2 and CaSO4 would interfere with the formation of Hg(ONC)2, but I could be wrong, and I belive that there is much more chance that the H2SO4 would interfere instead of the salts.




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[*] posted on 2-2-2011 at 06:10


Yesterday I made some Hg(ONC)2.

To cca. 6g of Hg i added 45ml of 60-70% nitric acid (which was made from NH4NO3 and boiled down battery acid in an extremly improvised and crude distillation setup, and then diluting it with water). After the Hg dissolved (it took around 15-20 min) I added 55 ml of denaturated 96% ehanol to the nitric acid/mercury solution. As the reaction didn't start I heated it a bit, then it vigorously started and was complete in a few minutes. The mercury fulminate was washed several times with water (untill the wash-water was neutral) and left to dry in the baker. Today while the powder is still damp I transported it to a sheet of newspaper.

It is not dry yet so I can't weigh it but I think that there are at least 5-7g of it.




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[*] posted on 6-2-2011 at 13:05


Is good cooper fulminates for uses like priming in gun caps?
I find that recipe to making cooper fulminates in book "Preparatory manual of explosives" and is easy to make but I don`t know how safety and useful is that



Copper fulminate
Use: Substitute for mercury fulminate.
Molecular weight: 147.584
Flammability: Explodes when ignited
Detonating velocity: Similar to mercury fulminate
Toxicity: Moderate
Sensitivity: Easily detonated
Classification: Primary explosive
Stability: Low
Overall value (as primary explosive): Low
Procedure 4-08A: Preparation of Copper fulminate
Materials:
1. 100 milliliters of 70% nitric acid
2. 30 grams anhydrous copper-II-nitrate
3. 120 grams 95% ethanol
Summary: Copper fulminate is prepared in a similar fashion as the mercury salt; by the addition of a hot nitrate acid solution upon ethyl alcohol. In this case, anhydrous copper nitrate is dissolved in nitric acid, the mixture is then heated, and the ethanol dropped in. As the reaction proceeds, the copper fulminate will precipitate. It is then easily filtered-off, washed, and dried. Note: Various modifications to this procedure exist.
Hazards: Use proper ventilation when handling 95% ethyl alcohol, and avoid inhalation of vapors.
Procedure: Place 100 milliliters of 70% nitric acid into a beaker, and then add 30 grams of anhydrous copper-II-nitrate. Note: if the copper nitrate fails to dissolve, add water drop wise, until the copper nitrate dissolves. Then rapidly stir this mixture at
room temperature for 24 hours. Thereafter, slowly heat the mixture to about 80 Celsius with rapid stirring, and then carefully add 120 grams of 95% ethanol while stirring the reaction mixture. After the addition of the alcohol, remove the heat source, and allow the reaction mixture to cool to room temperature. Afterwards, rapidly filter-off the precipitated copper fulminate, wash with several hundred milliliters of cold water, and then dry in a desiccator filled with anhydrous magnesium sulfate. Should be stored in a desiccator over sodium sulfate in a refrigerator.

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[*] posted on 6-2-2011 at 15:59


That method will not work. You can only make fulminates that way with mercury
and silver.


Check out "The chemistry of powder and explosives" by Davis.
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hissingnoise
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[*] posted on 7-2-2011 at 05:21


Quote: Originally posted by otonel  
"Preparatory manual of explosives"

The procedures in that book are not to be trusted!
Check out COPAE as gregxy suggested!
It can be downloaded from the site library . . .

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[*] posted on 7-2-2011 at 12:56


I actually went after that 2nd edition of that book because many of the patent # were incorrect. Later I thought it was a real waste of my time because if the guy didn't edit it carefully; why should I? The book is a mess partially due to some of the background (patent material) being quite true & some being much too obscure to verify.
I checked out his 3rd edition: same deal. - Not as bad but then there were some issues that were simply sloppy.
The copper fulminate issue was a sloppy mess. The addendum was "essentially "it's just like Hg fulmniate in process"....WHAT? :(

There are some others like ammonium chlorate and copper azide that are just dangerous "death mixes" & have no real value.
The author went from attempting to develop a company "Paranoia Publications" to a "print-as-you-sell" self publishing firm that essentially is designed for authors who want their "market feelers" in print so they can send them to large firms as an attempt as getting a contract.

The author also did some other works that I have a problem with. He wrote a book on chemical weapons that is a serious prescription for killing yourself with toxins. The CS & CN tear-gas synthesis were somewhat unclear. But basically the "heavy" stuff was not OK. The gentleman apparently has use of a VERY well equipped lab so that many of his synthesis in his explosives texts make use of the more (or most) expensive means to an end.

"Just pour the acetic anhydride from your gallon jug into your $60,000 rotary evaporator....." :D



[Edited on 7-2-2011 by quicksilver]




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[*] posted on 8-2-2011 at 03:30


Quote: Originally posted by gregxy  
That method will not work. You can only make fulminates that way with mercury
and silver.


Check out "The chemistry of powder and explosives" by Davis.


Or he could just have used the search feature and easily find this thread dealing with the very topic:

http://www.sciencemadness.org/talk/viewthread.php?tid=599&am...
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quicksilver
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[*] posted on 8-2-2011 at 06:51


The "fumes" of a proper fulmiate reaction produce acetaldehyde, ethanol in abundance which are set in a distillation-type condenser that is "recycled" back to more of the mercuric nitrate making for a very efficient production mechanism. The introduction of copper into Hg Fulminate yield a large level of HgNO3 in the finished product (a yellow fine powder) which basically ruins the energetic properties of that material.
There HAS been a great deal of differing fulminates & in an odd similarity to some other materials, some of the elements just don't have energetic properties while others are much too sensitive. The actual chemistry of fulminates was not clearly understood till quite a long time after it had been in commercial production. The isolation of fulminic acid had made some chemists believe that simple addition could produce the finished energetic; which didn't appear to be the case. (Davis)
There HAD been attempts to subdue the sensitivity of Ag fulminate by the addition of other metals but the results were not as predicted. The fulminates are unique.




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