Sciencemadness Discussion Board - Silver Fulminate Synthesis

Silver Fulminate Synthesis

AprenticeChemist - 22-2-2005 at 17:49

Ive been researching fulminates as I have finally gotten all of the chemicals I need to produce them. I have 200mls of 70% HNO3, and +500mls of Ethanol as well as about 2grams of Hg in my personal lab, not to mention a large ammount of other chemicals which I can obtain from my chemistry teacher. So ive decided this weekend im going to finally synth a few fulminates since I just got the ethanol today. Now ive been reading around and have found procedures for the Mercury fulminate and some for the silver.

Both synths are the same but from my research I found that it should be possible to skip the HNO3+Ag and use just AgNO3+Ethanol. Since this would save time and some precious HNO3 id like to try this methoud. The problem is I haven't seen any procedures for this methoud in fact ive seen only 1 or 2 synths of Silver Fulminate even using the normal way. I think im going to just calculate how much AgNO3 would be produced with the regular reaction and just add that to the ethanol. So does anyone know of a synth for Silver fulminate using the AgNO3 with just ethanol?

cyclonite4 - 22-2-2005 at 19:09

Look around the powerlabs website http://www.powerlabs.org, i think.

Careful with the silver fulminate, IIRC AgONC is so sensitive that the weight of the solid on top of a AgONC crystal below is enough to initiate it's detonation..

The reaction isn't just a nitrate with ethanol, it requires excess HNO3 to form a fulminate, otherwise you just have an ethanol solution of AgNO3.

Remember, make gram amounts, and be careful. Fulminates aren't friendly

.

EDIT: Fixed URL

[Edited on 23-2-2005 by cyclonite4]

Joeychemist - 23-2-2005 at 22:55

Right cyclonite4,
HNO3 must be present in the reaction. The HNO3 reacts with the ethanol to produce fulminic acid which reacts with the AgNO3 to produce the insoluble silver fulminate salt, which is why you have never seen a procedure for synthing it this way.

You may have luck adding AgNO3 to ethanol and then adding HNO3 to the reaction but sad to say you will have to use some of you’re most revered Nitric acid.

Edit]Siliver fulminate is EXTREMELY SENSITIVE as already mentioned, only work with small amounts.

[Edited on 24-2-2005 by Joeychemist]

cyclonite4 - 24-2-2005 at 03:07

I remember a recent thread on RS, by tom haggen IIRC. NBK, i think, mentioned that large amounts crystallizing out of a solvent can detonate, by their own weight initiating them.

AprenticeChemist - 25-2-2005 at 15:03

Yea after more research ive found that I will have to use my precious HNO3. But after my results with mercury fulminate, using 10mls of HNO3 would be worth it for the silver fulminate. I too have heard that it can detonate under its own weight at a certain ammount, I think it is like 2-3grams but im not sure it may be less.

tom haggen - 25-2-2005 at 15:44

If your going to be messing around with silver and nitric acid i would suggest synthesizing siver acetylide.

cyclonite4 - 26-2-2005 at 04:36

I second that... silver acetylide is also quite interesting.... an explosive that releases no gas...

Also, theres no need for absolute ethanol, just acetylene

Skinflint - 1-3-2005 at 10:18

I'd just like to say that most people are actually going to make the double salt. Double salt does produce gaseous products because it's formula is Ag2C2.AgNO3 so CO2 will certainly be made upon detonation. Your correct that true silver acetylide (Ag2C2) will only have atomized Ag and C as products. People rarely make Ag2C2. It is very sensitive and is made by bubbling acetylene through an Ag solution in alcohol (this is what my Organic Chem book said).

[Edited on 1-3-2005 by Skinflint]

AprenticeChemist - 1-3-2005 at 16:15

Actually I do plan on makeing some Silver Acetylide as well. I probably will make both the regular acetylide and the d-salt as well. I haven't gotten around to getting the silver for the Silver fulminate yet but I should get around to it soon. And yes you just bubble acetylene gas through a silver salt in solution to get the regular form of Silver Acetylide.

Quince - 5-3-2005 at 04:26

What about silver picrate? I see it mentioned many places, but did not find synthesis. I do not have any silver salts such as nitrate, but I have 99.9% pure silver. As I have no nitric acid yet, is there any other soluble silver salt I can make from the metallic silver and react with picric acid to produce a picrate?

[Edited on 5-3-2005 by Quince]

Joeychemist - 5-3-2005 at 11:04

I believe I have seen a mentioning for silver picrate in PATR 2700.

Now everyone forget silver acetylide and silver picrate, this thread is titled silver fulminate and that should give you a pretty good idea to what the thread is 99.9% about.

redneck - 7-4-2005 at 03:23

Hi guys, had an interesting dream a long time ago.

Silver fulminate synthesis

This is a fun explosive because it would be suicidal to make enough of it to fill a blasting cap with. If you dissolve it in ammonia and wet sand with the solution and let the ammonia evaporate you get fulminate coated sand. You can wrap several grains (pieces not the unit of weight) of the fulminate coated sand in paper. This will explode when dropped on the ground.

Dissolve in a test tube 0.5 g Ag in 4 ml HNO3 (50 % HNO3 containing, more concentratet HNO3 can`t keep the AgNO3 in solution). Don`t warm to avoid NO2 production.
Insert a glass thermometer into the test tube.
Make a mixture containing 95 % EtOH (94% white spirits is OK, no absolute alcohol neede) and 5 % CH3COCH3 (pure EtOH won`t work).

Stand the test tube in a small pot filled with water.
Insert 8 ml of the EtOH mixture into the test tube and stir with the thermometer.

Slowly warm the pot with the water and the test tube in it and watch the temperature in the test tube all the time.

Hold the temperature for 20 min between 55°C and 60°C(no NO2 and no fumes will be produced, just a small amount of CO2). After 10 min white shiny crystals should appear.This is the AgONC. Above 65°C the solution gets cloudy and green mud settles at the bottom. This means that the silver fulminate decomposed to useless silver oxide. So look at the thermometer all the time.

Add the contents of the test tube in a filter and rinse with 40 ml tap water. Then air dry. Don`t warm or lay it into bright sunlight.

Yield will be slightly below 0.1 g . But it would be dangerous to make more of the stuff.

It is unbelieveable sensitive. Amounts of less than 10 mg will detonate when lit by flame.
It is at least ten times more shock and friction sensitve than acetone peroxide.
It is also extremly sensitve to sparks generated by static electricity.

You should wear protection glasses when making the stuff. Post your results!

Good luck !!!

PS: This ist the russian original. But I assume that it doesn`t work because the temperatures it states are too high.

the method of synthesis.

This method is most close to the classical (from alcohol - to very in detail described in Shtetbakhera) - with that difference, that, as shows experience (and they also confirm the number of the materials of network), the synthesis of fulminate by interaction of ethyl alcohol with the nitric acid the solution of silver gives the very poor results (extremely small outputs with the low quality of product) or not at all it goes. In my view, this is connected with the quality of utilized alcohol - with the classical method alcohol must contain significant quantities of well-defined admixtures; pure alcohol gives the worst results.
The prescription given further is the combination of classical procedure and that previously worked out of &.tsuot;kholodnogo&.tsuot; method, and it was optimized to the achievement of the maximum brisance of product. Necessary reagents: metallic silver, nitric acid (65-70% solution), acetone (it is suitable technical), ethyl alcohol (in essence it were used 90-95% technical, sustained above the tempered silica gel into 1/3 volumes). Equipment: measuring cylinders 25 ml, small (measured) cone 25 ml, the registrar of temperature, reactor, beaker 50 ml (for the flushing), mixer (thin textolite strip or the rubber-lined glass rod). The registrar of the temperature - either the thermometer (20- 100C) with the rapid response, which makes it possible to read indications from rastoyaniya 2- 3m, or electronic thermometer with the temperature-sensitive element in the glass envelope (it were used the compensated thermocouple chromel-alumel with the amplifier and the digital voltmeter). To the tip of the shell of thermocouple (to the thermometer bulb) stretches the section of teflon tube (1 2cm) with the lateral cuts for guaranteeing the thermal contact with the liquid.
Reactor (simple) - thin-walled beaker 100 ml in ceramic container 200 300 ml; into the containers are introduced the thin (inside diameter 2mm) polyethylene (or PVKH) tubes, which go to the operator. In the external container the shear of tube concerns the bottom, in the internal - it does not reach the bottom to 4 5cm. From other side to the tubes are connected the medical syringes (to 20- 50 ml), filled with cold water. On top small container is loosely covered by the light cover (for example, by plate from polyethylene). Attention! for the the clear of &.tsuot;zapuska&.tsuot; reactions both containers preliminarily progrevayutsya to ya0-.shch0Ch. Reactor (complex) - the thin-walled glass beaker 100ml sufficiently tightly is put into the aluminum heat-insulated container (from 1-2 ml waters), cmbined with the powerful (not less than 30W heat output) refrigerator of Peltier (on the appropriate radiator). The regime of refrigerator (nagrev/okhlazhdeniye) is regulated by the electronic thermostat, connected with the temperature sensor of reaction. As in the simple reactor, into the container is introduced the tip of the long tube, which is concluded shityu shpritsom with the cold water (for the the emergency of &.tsuot;gasheniya&.tsuot; reaction).
Complex reactor makes it possible to easily obtain product with the accurately specific properties. But in any event it is necessary to completely exclude the entering of the gaseous reaction products into the accomodation (i.e. reactor it is established either in the exhaust hood or on the street), since they are highly toxic and possess the expressed terratogennymi properties.

Stages of the synthesis:

1) is prepared in the covered test tube mixture 11 ml alcohol and 3 ml acetone (with the decrease of the content of acetone in the mixture hinders &.tsuot;zapusk&.tsuot; of reaction is reduced output, with an increase reaction too stormy, can occur overheating and decomposition of fulminate);

2) reactor progrevayetsya and further it is supported with 40- 45C;

3) into the small cone are poured 10 ml solution of nitric acid, then they are added 1.2g preliminarily weighed metallic silver (in the pieces or the wire); cone loosely is covered and is placed on the hot (80- 90C) water bath - occurs the violent reaction of the dissolution of silver with the isolation of the significant quantities NO and NO2 (ventilation, thrust);

4) immediately on the dissolution of silver into the internal container of thoroughly heated reactor is poured the mixture of alcohol and acetone, further - the brown acidic solution of silver, everything rapidly gets mixed (by rocking); in the mixture descends the temperature-sensitive element and water tubes are introduced; internal container loosely is covered; an increase in the temperature of mixture begins 15-30 seconds after mixing and the isolation of a large quantity of toxic it is steam; if reaction for some reason or other does not begin (for example, with the dissolution silvers are great loss NO2), then it is necessary to additionally warm up mixture (in the second version of reactor - by the reverse of the refrigerator of Peltier, in the first - for example, by introduction into the partition of the containers of hot water);

5) after reaching 75- 80C temperature is maintained (via vvedeniya/otsosa of cold water into the partition of containers in the simple reactor or by electronic thermostat in the reactor with Peltier) in limits of 75- 82C (more precise values they depend on the inertness of system they are selected in the experience); if occurs the uncontrollable increase in the temperature more than 85C, then IT IS NECESSARY TO IMMEDIATELY INTRODUCE INTO THE INTERNAL CONTAINER (ON THE TUBE, SHPRITSOM) COLD WATER FOR THE SHARP STOP OF REACTION - OTHERWISE WILL BEGIN THE STORMY DECOMPOSITION OF FULMINATE I, PROBABLY, IS POSSIBLE EXPLOSION;

6) with the normal flow reaction in concludes approximately in 10 minutes; end point is fixed on the curtailment of heat liberation and the beginning of cooling; further cooling can be accelerated by introduction into the partition of the containers of a significant quantity of cold water or by start of Peltier's refrigerator; on reaching 20C (desirably - below) into the internal container along the tube it is introduced 20-30 ml the cold distilled water; further reactor is opened, tubes are moved away and THE TEMPERATURE-SENSITIVE ELEMENT (necessary to exclude any action on the sediment), VERY ACCURATELY TAKES OUT ITSELF; internal container takes out itself also after brief settling from the sediment carefully it merges liquid;

7) sediment carefully shakes up with 3-4 small (on 10 ml) portions of water and merges into the container for the flushing (to 50 ml); the liquid merges after settling, then are poured 40 ml the distilled water and are mixed (by rubber-lined rod); further mixture is defended and liquid merges;

8) the operation of flushing is repeated 7-10 times (desirably, before the disappearance of bitterish smell); in any stage in the flushing it is possible to use water with the tracks of chloride ion (for example, the chlorinated water from under the crane);

9) for the storage by pipette with the soft tip the washed clean sediment is transferred (with the part of the liquid) into the penicillin phial; under the layer of water with plotny to thrombosis the fulminate is stored safely and unlimitedly for long;

10) so by pipette fulminate can be transferred into the funnel with the paper filter and filtered; after the runoff of liquid the filter with the sediment takes out itself and is plotted (for additional drainage) to 3-4 layers of filter paper, and further it is dried in the dark place at room temperature;

11) the dry fulminate of silver is stored in the cool dark place for those covered directly into the filter and the additional thin paper, roll is plotted in the empty match of boxes; with initial the quantities indicated are obtained 1,5- 1.6g fulminates (i.e. output 90 96% of the theoretical) in the form of the smallest silvery white fish-scales; if fulminate takes the form of yellowish (to the light brown) powder, then overheating was allowed with the synthesis, the partial decomposition of product occurred and its brisance was reduced. The remainder of mother liquor and wash water is recommended to mix with 10-20 ml of 5-10% solution NaCl - this it precipitates the remainders of silver in the form AGCl. Sediment several times by decantation washes in water and it is filtered. To precipitate (to defend) sediment, and also to dry and to store AGCl is desirable in the darkness.
Obtained AGCl it is possible to add with the synthesis of fulminate to the nitric acid (to 10% additionally to a quantity of metallic silver). This additive, practically without influencing the brisance of product, increases its output. To plasticize the fulminate of silver is possible either with traditional means - by mixing to the finished fulminate plasticizer (possibly, with the volatile solvent), or the dissolution relative to inert plasticizer in the alcohol-acetonic mixture directly before the synthesis. In particular, was tested addition (with the indicated procedure synthesis) 0.3g dinitrotoluenes (DNT) - in this case fulminate were separated not by fine scales, but it were cemented into the sufficiently long soft needles. The compressibility of this product is sufficiently great, and the losses of brisance are lower than with other tested methods of plasticization. In also the time from the admixtures it washes clean with difficulty and requires more thorough washing; its shock sensitivity (however, as with the usual plasticization) somewhat higher than clean fulminate.

the syntheses of the fulminate of silver

synthesis 1 The standard method of obtaining fulminic silver is based on interaction of ethyl alcohol and nitric acid solution of silver. Known also that alcohol (as the supplier of methyl groups) it can be in this reaction substituted with other substances - in particular, acetone. Moreover fulminate is obtained under the effect of acetone and nitric acid on silver nitrate already at room temperature. However, a similar synthesis occurs by exceptionally unstable in view of tendency toward the self-accelerating decomposition not only of the resultant fulminate, but also acetone- acidic mixture. Therefore were investigated some possibilities of the stabilization of a similar synthesis - in particular, conducting reaction in the presence of the passivating solvent, as which satisfactorily recommended itself acetic acid. It is immediately necessary to note that fulminic silver, obtained on writing presented below, contains the noticeable admixture of acetate and is differed from that described higher than &.tsuot;goryachego&.tsuot; fulminate by somewhat larger sensitivity to the mechanical actions. Necessary equipment: small cone 25 ml, pipette with the soft tip, filter, small measuring cylinders or graduated pipettes, weights, container or cup for the water bath, it is desirable - refrigerator. Necessary reagents: nitric acid (with density of 1,42 g/cc), acetone (it is suitable qualitative technical), acetic acid (completely it works 70% food), metallic silver (in the wire or the trimmings).
Stages of the synthesis: 1. into the cone are poured 4 ml nitric acid, where are added and get mixed 2 ml acetic acid; 2. further there are poured 2 ml acetone (mixture in this case slightly it razogrevayetsya) and they rush by 0.5g silvers; cone loosely is shut (for example, by the crumpled teflon film) and is placed in the container with the layer of cold water; container is placed in the dark cool (10 15C) place on day; Note: The mixture because of the possibility of self-heating in question is so inclined to the violent reaction of decomposition with the ejection of acidic solution and toxic it is steam; the improved heat withdrawal (through the water) and a reduced temperature prevent decomposition. 3. in days the large part of silver passes into the sediment of the white lamellar crystals of acid nitrate; further another twenty-four hours container with the cone is maintained at room temperature (20- 25C); the remainders of silver in this case are dissolved, acid nitrate is converted into the fulminate, and sediment acquires a somewhat amorphous form; 4. on the completion of endurance acidic solution accurately is drawn off (by pipette with the soft tip) and sediment in the cone of 4-5 times directly washes in the small (on 10 ml) portions of water; the washed fulminate washes off to the filter, it is filtered it is dried analogously with points 10) -11) &.tsuot;goryachego&.tsuot; the synthesis of fulminate; output of approximately 0,65- 0.68g white powders from the amorphous- lamellar crystals. As in the case of &.tsuot;goryachego&.tsuot; synthesis from the acidic the solution and the wash water one should precipitate the remainders of silver in the form of chloride. It should be noted that in conclusion temperatures indicated in the writing and duration of both stages are, in general, recommending. Actually optimum conditions will be determined by the concentration of the utilized nitric acid, by the presence of admixtures in acetone and silver, so forth in principle, entire synthesis can be executed, also, at room temperature. However, the rise in temperature of reaction (especially during the first stage) increases the risk of the stormy decomposition of mixture. Reduction in the temperature or decrease of the duration of the second stage leads to the decrease of output because of the incomplete conversion of sediment. Increased duration or temperature cause the gradual decomposition of the synthesized fulminate - it acquires first yellowish, and further brown painting and grain structure; brisance and its durability in this case are reduced, and sensitivity grows. Clear red small crystals appear with an even long exposure in the sediment - probably, salt of nitronic acids. Mikhail @mihailru.freeservers.com

[Edited on 7-4-2005 by redneck]

[Edited on 7-4-2005 by redneck]

chemoleo - 7-4-2005 at 08:36

Yah, redneck/cyclonite, I just removed this argument, it served no point.

Redneck, it obviously is ok if you got the info from somewhere else, as not everyone can be expected only to post radically new methods&inventions here. If you don't remember where you got it from, so be it, although references are of course always appreciated. As long as you don't claim it's your patentable invention

I wonder though - the yield of 0.1 g is very low, considering you start off with 0.5 g of Ag?

At least you can recycle the Ag, I presume (reduction & precipitation)?

[Edited on 7-4-2005 by chemoleo]

Rosco Bodine - 7-4-2005 at 08:48

http://mihailru.freeservers.com/

redneck - 7-4-2005 at 09:16

Silver is cheap enough(round about 30 cents per gramm) that its not worth the work recycling it in so small amounts.

If you want a higher yield try out the same amount of a 80% EtOH 20% CH3COCH3 mix. This could give you a four times higher yield. But That`s just a guess. But I prefer a lower yield instead of risking to have glass fragments sticking in my face.

I dreamed that other recipes without CH3COCH3 lead to no AgONC at all.

The_Davster - 7-4-2005 at 16:44

Rosco, how do you view that site? I get a bunch of weird characters, it must be encrypted?

EDIT: Ohhh....stupid me...really should have read the first few lines on that page instead of skipping right ahead to the chemical links.

[Edited on 8-4-2005 by rogue chemist]

Rosco Bodine - 7-4-2005 at 16:54

It's a secret , Shhhhh.

In the toolbar of Internet Explorer
pull down the menu under " view "
and select for " encoding " UTF .

You will also need browser language support installed for cyrillic characters .

Then you can copy and paste the Russian
text into a Chemistry specific translation engine , all of which are not so great

silver fulminate

ssdd - 15-4-2007 at 06:34

Ok so a while back now I tried to prepare some silver fulminate.

I used the following method:
1. Heat 8-10 ml of Nitric acid to 40*C.
2. Dissolve 1 g of silver into this. (I ran into a issue where the metal was passivated by the acid and had to add water to get it to dissolve.)
3. Pour this mix into 15-20 ml of ethyl alcohol that has been chilled to 10*C, keeping the temperature below 18*C.
4. Allow this to sit for 15-20 minutes. (I noticed a small white precipitate that began to form.)
5. Add 200-250 ml of cold water to further precipitate the crystals.
6. Filter them out.

I did all of this and I ended up with a very very small amount of Fulminate in the end, so little that I couldn't get it to react. Are any of these steps wrong or what could I have done wrong?

Any help would be great.

Axt - 15-4-2007 at 07:16

You left it too cold. Fulminates are hot and ugly reactions. See the attachment for what seems to be the most modern published synthesis of silver fulminate. They start with silver nitrate though disolving Ag into HNO3 should work as well or better due to residual NOx triggering the reaction through oxidation of the ethanol. Though with this said, I've never had luck with silver fulminate using hardware store bought "methylated spirits" as the ethanol, which works fine for mercury fulminate.

What you filtered was most likely AgNO3, if it were AgCNO there no way you would have "so little you couldnt get it to react".

[Edited on 16-4-2007 by Axt]

Attachment: A Reappraisal of Silver Fulminate as a Detonant .pdf (487kB)
This file has been downloaded 5603 times

wow

ssdd - 15-4-2007 at 07:30

Wow, they take it as high as 68*C. I would never think to let it get that hot. Now I have to ask since it seems I lack in the dry silver nitrate department. Would adding silver metal to nitric acid have the same effect in the end? It seems logical that silver nitrate would be formed somewhere in that. Ill have to re-run my experiments with this method.

Just out of curiosity, what formed in the first reaction I outlined then?

Axt - 15-4-2007 at 07:51

Adding ethanol would probably have precipitated some of the AgNO3 formed via dissolving the Ag in HNO3. Though if anything remained after diluting it with that much water, yet still failed to respond to ignition, who knows. Here the synthesis from PATR2700 vol.6 F224, from elemental silver.

1)To 1 g of pure silver powder, placed in a flask, was added a mixture of 8.5g of nitric acid (d 1.42) & 1.2g water preheated to 90-95° and this was left at RT until complete dissoln of silver.

Note: All these manipulations were conducted under the hood behind a safety screen.

2) The resulting soln of Ag in dilute nitric acid had temp of 60°C. It was carefully added to a 150-ml balloon flask provided with a thermometer and contg 12.25g of 95% ethanol (preferably not denatured).

3) The flask was then placed in a trough I which could be filIed with either cold or hot w. The temp in the flask was kept below 60°C by cooling the flask, if necessasy. If the reaction started to slow down, the flask was slightly heated by adding some hot w to the trough. If some brown fumes started to appear in the flask the reaction was slowed down by cooling the flask under cold w tap. Note: As the fumes evolved during this operation are very toxic, care was taken not to inhale them.

4) As the reaction proceeded, all of the SF precipitated in about 20 mins, giving practically 100% yield.

For the plant procedure, Livingston recommended using 10-15g of silver and to increase the amounts of other ingredients correspondingly.

[Edited on 16-4-2007 by Axt]

ssdd - 15-4-2007 at 08:12

Well no wonder it didn't react if all I made was Silver Nitrate. But that explains when it didn't react after hitting it, I tried to light some filter paper that had a residue left on it on fire. When I did this it simply burnt with a mildly increased flame where, what I now presume was Silver Nitrate, was. It also left a oily residue behind, which I'm guessing was just leftover from the acid/ethyl?

Heres a video of the burning, nothing to spectacular minus the minor mishap at the end. http://s97.photobucket.com/albums/l223/ssdd534/?action=view&...

Thanks for the instructions above I'll give them a run when I get the chance.

The_Davster - 15-4-2007 at 10:21

I used to enjoy silver fulminate. It is really nifty if you only work small scale, and keep the majority of it under water.

If you use less reagents then the ammounts in the procedure in your first post, the reaction of the acidic nitrate solution with alcohol will not have enough 'critical mass' to react producing fulminate. I somehow survived(

) and managed to make the fulminate by boiling the solution with an alcohol burner. I did that once, and really do not recomend anyone try that for themselves. Heating was continued till the reaction started, as evidenced by the gasses produced.
I really don't recomend working below the 1g silver starting, due to the extra heating that must take place. I always found that adding the hot(pretty much boiling, just cooled briefly) acidic silver nitrate solution to warmed alcohol would get the reaction started quick,and it would not require more energy to get the reaction going. After that adding water would produce 'enough' silver fulminate. I never once dried it all at once, so I never took a yield, but there was more then enough fulminate for a while. Just washed the fulminate a lot and stored it under water, removing very small ammounts as necessary(with a soft wooden stick). NEVER USE A GLASS STIRRING ROD at any step in which you have a precipitate of the fulminate, it can grind the crystals and have them explode, even under water. Only swirl.

I also do not recomend more than a gram of silver for starting either. This is obscenly sensitive stuff. I've had a couple minor accidents from it exploding under water.

Have fun. but be careful.

[Edited on 15-4-2007 by The_Davster]

ssdd - 15-4-2007 at 12:35

Yea I've had one Silver Fulminate accident some time back now. When I was first starting out with my interest in pyrotechnic material I thought it would be a grand idea to take the little snaps you chuck at the ground and pour the contents of a few into a film canister. After about 5 of them it went off in my face with a great deal of sound and some small sand getting thrown around pretty hard. I was lucky not to loose an eye.

Now I'm just wondering. If this other method I had originally used to produce the Fulminate is wrong, how come many others say it works? Or are they just bluffing.

Now when a fulminate is set off what exactly happens? By this I mean what bonds are broken? My guess from what background I have is that the O-N bond breaks leaving AgO and NC?

Levi - 15-4-2007 at 13:59

This would be my guess for the decomposition of silver fulminate:
2AgCNO --> 2Ag + N2 + 2CO

Of course the heated products in an oxygen atmosphere would probably form carbon dioxide, silver oxide and some NOx.

What is the exact mechanism for the reaction between silver nitrate and ethanol? I can't figure out where the CN bond is coming from.

quicksilver - 16-4-2007 at 07:17

I have had difficulty getting silver to dissolve fully in acid and found a trick to accomplish this......
Use silver wire! The smaller the size of the material the better. Note how AXT used powder. And then add a drop of water to the metal itself! Let's say you don't have silver wire, get some silver and cut, rend or hammer it into a small piece. Then get it wet with water and THEN place it within the acid. The water provides an O source for the start of the reaction and then it will continue with little fuss. Some people used to suggest drops of water to the acid directly, but if you put it on the metals the reaction is much faster.

True detonation is a VERY interesting thing. TATP does not detonate according to the classical definition. But fulminates, styphnates, picrates, & azides do! The bonds do break. And this can happen on a very tiny level. A single crystal of lead styphnate when held on the tip of a needle will "pop" and a tiny sound can be heard! Same for fulminates; you can work on a micro scale.

Often the addition of starch to the Ag fulminate will "buffer" it so that it might be worked with in a somewhat safer manner. But the best suggestion is to keep the whole of the experiment small. To me even a gram is a fair size batch

To the best of my knowledge the above decomp formula by LEVI is correct: 2AgCNO --> 2Ag + N2 + 2CO. There are areas that may have some alteration such as the environment of the material influencing the resultant but I think it's right on the money. That's why it's so interesting.....it really breaks apart.

Get a good book on detonation modeling and read it very slowly....it's really something.

Also, asking questions here won't get you banned or yelled at.

ssdd - 16-4-2007 at 07:35

I may ahve some silver wire laying around amongst the masses of computer parts in my basement. That sounds like a safer/nicer way of going about this than just taking the silver powder and dumping it into the acid which realeases tons of NOx gas.

I am guessing because the triple bond bettween the Carbon and Nitrogen is where alot of the energy of the detonation comes from.
Any hints as to where I can find a book on detonation modeling?
(On the last line; Yea I was banished from roguesci (suprise!) for this same topic...) :mad:

gregxy - 16-4-2007 at 09:19

I remember making silver fulminate 30 years ago when I was a teenager. We broke a tine off of a sterling silver fork, disolved it in HNO3 and added ethanol. The mixture heats up and starts to boil and white powder percipitates out.

The reaction from alcohol to fulminate is described in the Davis book and has 6 or 7 steps. However it may also be possible to make fulminates from nitromethane. The reaction
from HNO3 and ethanol requires mercury or silver since the
fulminate salt must be insoluable in the acid mixture to
form a percipitate.

silver fulminate is described as too sensitive to have any practical use, probably similar to TATP.

I was injured by it along with my friend when some fulminate that we had in a glass vial under water exploded. (We were
cut by the flying glass and our ears were ringing for about a week). I was very lucky not to loose an eye from the accident.

Never make more than a gram of this kind of stuff.

Rosco Bodine - 16-4-2007 at 09:24

There is also some more information in US4270435
and a bit more discussion in

https://sciencemadness.org/talk/viewthread.php?tid=1778&...

and

https://sciencemadness.org/talk/viewthread.php?tid=350&p...

[Edited on 16-4-2007 by Rosco Bodine]

chemoleo - 16-4-2007 at 17:32

If there are any posts on Silver fulminate that require moving/merging/deleting, let me know.

ssdd - 17-4-2007 at 02:32

Thanks for merging these.

I think I am going to revisit my work with fulminates tomorrow. Now that I have proper directions for producing it it should go better.

I must say the Fulminate molecule is pretty interesting now that I have looked into it more. What I didn't know, as a few outlined above, is that the fulminate can detonate while submerged under water.
Would working on a scale of .5 grams of dissolved silver be a safe level to try this. Some of the places I looked said that it may not be enough silver to maintain a reaction. Can anybody verify this?
Also, what are some suggested detonation methods for this that can be safely done in a high school lab?

Thanks for your help.

quicksilver - 17-4-2007 at 06:12

Quote:

Originally posted by ssdd
Any hints as to where I can find a book on detonation modeling?
(On the last line; Yea I was banished from roguesci (suprise!) for this same topic...) :mad:

A really good one is written by Fickett & Davis ( Detonation ). It is a good idea to spend a really long time on the first two chapters as it uses them for the rest of the book and all the modeling concepts.

Most everyone here has been banned from there or just simply stopped posting there. It's fucking amazing how many people here also don't care about racial hygiene or killing dogs. (yes, NBK)

GAHHHH!!!!1!

ssdd - 18-4-2007 at 07:41

Ok so I reattempted Silver Fulminate today. And yet again it failed. Heres what I did:
1. Dissolve 1.1 grams of silver into 20 ml of 3 molar Nitric Acid.
2. I heated this to 84*C, some NOx gas was realeased.
3. I let it cool down to about 60*C.
4. Added 20 ml of Ethyl.
5. Maintained the tempature of the liquid at 65*C for 25 minutes.
6. Let it start to cool, then added 100 ml of cold water.
The liquid became a milky blue/white. I attempted to filter it and was given a very small yeild of a shiny white material. This all seems to go wrong at the end. What on earth happened, or better yet did I mess up somewhere along the way?

The_Davster - 18-4-2007 at 15:35

You should have used concentrated nitric acid. The stuff you used is too dilute for the reaction with alcohol to occur.

quicksilver - 19-4-2007 at 05:15

Quote:

Originally posted by ssdd
Ok so I reattempted Silver Fulminate today. And yet again it failed. Heres what I did:
This all seems to go wrong at the end. What on earth happened, or better yet did I mess up somewhere along the way?

Let's go for something that you can get a fulminate with first. Why don't you try using mercury and adding a wee bit of silver to that? The reason I offer this approach is that in that, you may find where the real problems lay......Mercury dissolves rapidly in HNO3 and provides a "carrier" for a few other metals that will make energetic fulminates. PLUS it's much less sensitive. but if you don't have any Hg here is what I can offer at this juncture.....
You see, fulminates are occasionally a "feel" project in chemistry. I know that sounds very unscientific but there are some things that can go wrong with the reaction in terms of timing and contents.
I'll tell you RIGHT NOW that one of the biggest problems I have heard of in making fulminates are these:
1- YOU MUST USE REAL ETHYL ALCOHOL. Using anything but 190proof grain ethyl alcohol (the shit you drink!) will result in problems (inconsistent results guaranteed).
2- The temp of the reactants should start at room temp and move up. Start at lower than 20C and you will have a delayed reaction that may "spike" too quickly with the introduction of heated material.
3- When you make a nitrate suspended in acid - DON'T MIX IT. Let it stand as it dissolved. This is a unique issue that has little explanation other than it was a standard in Germany during fulminate production and does seem to be quite valid. (My German is poor but I read about it in a wonderful text written in 1911 from a factory over there).

Think it over....do ANY of these apply?

ssdd - 19-4-2007 at 08:20

Ahhh I see. When I was dissolving the silver I had it on a magnetic stirer. As you explained this could be the issue I encountered. Does anyone have any ideas whats happening here, after taking a gander around I couldn't find much. I may try it with mercury.
Just a quick update:
I let the beaker with the Blue/White solution sit overnight. When I came into the lab the next day I found a layer of gray powder on the bottom and the liquid was clear. I decanted off the extra liquid and filtered out the powder. It is drying right now and I'll know tommorow if it reacts at all. There was perhaps a .1-.2 gram yeild of this.

Axt - 19-4-2007 at 09:56

Quote:

Originally posted by ssdd

I let the beaker with the Blue/White solution sit overnight. When I came into the lab the next day I found a layer of gray powder on the bottom and the liquid was clear.

Are you using distilled water? if your using tap water you are likely precipitating say... silver chloride.

ssdd - 20-4-2007 at 12:26

Ok I attempted to set off the gray precipitate today. Yet again there was no result. It did not respond to impact or flame. When I burnt the filter paper that it was on it turned a green/gray and did not turn to ash.

As it was pointed out using tap water could make an issue. My guess that this gray ppt was simply silver chloride or something similar. Stupid me... never took tap water into consideration. For now I have given up on silver fulminate, there are just to many ways to mess it up.

Thanks for everyones help.

gregxy - 20-4-2007 at 13:02

As was mentioned earlier, your 3 M HNO3 is too weak. I used 70% d=1.42 nitric acid and it worked for me, I think 70% should be about 15 molar.

ssdd - 20-4-2007 at 13:49

When I had first tried the fulminate I used a 15.8 molar nitric acid. I ran into the issue of the silver not dissolving because the silver was pasivating. If there is a way around this I would love to know for future reference.

The_Davster - 20-4-2007 at 14:14

How odd, I have never experianced such things. What form is your silver in? I usually use a chunk hacked off a 1oz ingot, this exposes fresh silver to react , perhaps your silver has become passivated before adding to acid from H2S in the air?

Magpie - 20-4-2007 at 14:34

This may help:

http://www.sciencemadness.org/talk/viewthread.php?tid=2772&a...

ssdd - 20-4-2007 at 15:00

The silver was in a powder form. I think it may have been a silver alloy in that the nitric turned a lovely shade of green when the powder was added.

When I added the silver to the 3 molar acid all of it disolved with the liquid turning a light blue color. I'm not sure if this color diffrence means anything...

any thoughts?

not_important - 20-4-2007 at 15:54

How was the silver shot labeled? What I've seen is generally 99.9+ % silver, but you can get alloys - I'veen both sterling which has copper and a silver-nickel alloy.

Either one may cause problems when making fulminate, and it does sound as if you've copper in there.

The only passivation with silver that I have heard of is 1) electroplating a thin film of tin onto the silver, not likely for shot, and 2) if there is chlorides in the solution in which case a layer of sliver chloride can be formed.

I've never had problems dissolving pure or sterling silver in clean nitric acid of any reasonable strength.

Levi - 20-4-2007 at 18:30

Quote:

Originally posted by ssdd
When I burnt the filter paper that it was on it turned a green/gray and did not turn to ash.

The comment about it turning green near burning filter paper sounds like CuCO3. NiCl2 is green also but it would have been that way even before you burned the paper.

nitro-genes - 21-4-2007 at 06:56

The fulminate reaction with silver seems pretty sensitive to impurities, more so than mercury at least ast that worked fine with me.

If alloyed silver is your only source, you could purify it by precipitating a small amount of silverchloride with NaCl, thoroughly washing it, and then strongly heat it to yield pure metallic silver and chlorine gas. Silver is one of the few insoluble chlorides, so this should eliminate most of the impurities.

not_important - 21-4-2007 at 07:48

Quote:

Originally posted by nitro-genes...
If alloyed silver is your only source, you could purify it by precipitating a small amount of silverchloride with NaCl, thoroughly washing it, and then strongly heat it to yield pure metallic silver and chlorine gas. Silver is one of the few insoluble chlorides, so this should eliminate most of the impurities.

Seeing as silver chloride has a listed boiling point of 1550 C, there may be some problems with this approach.

A classic method of converting AgCl to the metal is fusion with Na2CO3. There are others as well.

nitro-genes - 21-4-2007 at 08:50

Since most silverhalides spontaneously decompose under the influence of light I thought it might be easily reduced by adding charcoal or decomposed by heating alone, but apparently this is not the case for the chloride. It's not considered to aid in combustion according to it's MSDS so directly reducing it probably doesn't work either.
You could always use more classic approach, like dissolving the silverchloride in ammonia and adding some formaldehyde to reduce it to silver, maybe vitamine C would work as well. After that you could directly wash the silverfilm of the inside of the glass beakerwith some nitric acid to yield a very pure silver nitrate solution.

Just tried with ascorbic acid, adding a filtered solution of ascorbic acid derived from vitamin pills instantly reduces Ag+, moreover it doesn't form a film on the glass like formaldehyde does but appears like a dark grey/blueish suspension which could be filtered off without much trouble. terribly impractical for purifying large amounts but it suffices for small amounts. I might use the same procedure for purification to experiment with silver azides and complexes thereoff, in which copper impurities are highly unwanted as well...

[Edited on by nitro-genes]

nitro-genes - 21-4-2007 at 11:50

Did the synthesis myself too, since I couldn't imagine why the reaction yielding silverfulminate would be sensitive to impurities, while with mercury this isn't a serious issue at all. So I dissolved 0.2 grams of fairly impure silvernitrate in 2 ml of demineralised water, added 2 ml of 70% nitric acid and 3 ml of denaturalized ethanol (methanol and pyridine impuritues) and kept temperature at around 60 deg C.
The moment the mixture became about 50 deg. the reaction began, evident by slight bubbling. At the bottom of the test tube some white clouding could be seen at first and after 10 minutes or so white feathery aggregates of SF started to form. The final yield was much higher than on the photo, which was taken after about 10 minutes.
After the reaction was complete, the acid was decanted and the SF dissolved in ammonia after which ascorbic acid was added to destroy the SF. I felt no need to experiment with it due to it's sensitivty.

[Edited on by nitro-genes]

SF small.jpg - 12kB

ssdd - 21-4-2007 at 12:07

Quote:

My main question to this would be: Are you reacting this with the silver alloy or the silver chloride you mentioned?

This is a obvious question, but how did you go about deriving the acid from the vitamin pills? This sounds like a good method that may actually work for me... I'm also thinking my issue may have been with tap water. The iron content in my towns water is very high and the pipes at the school are fairly old. So my guess would be that it could have given me some issues.

Sobrero - 21-4-2007 at 12:48

I doubt you have to purify your silver; as nitro-genes already stated the SF synthesis is quite tolerant towards impurities. I also prepared SF today

, proving this synth doesn't need high grade chemicals at all.
I used 1.10g silver from a silver spoon (let's say 90% silver with copper, nickel, ... impurities), 10ml denaturated ethanol and 10ml 60% technical grade nitric acid and following Axt's procedure on the first page of this thread.
Yield seems to be almost quantitative, as indicated by Fedoroff. I know that nitro-genes, who used approximatively the same synthesis, checked if Ag(+)-ions were present in the filtrate by adding tap water, and the solution just turned very slightly white, indicating an almost 100% yield.

analogues of fulminates

Rosco Bodine - 21-4-2007 at 13:02

The famous explosives researcher Munroe ,
made an interesting note concerning which I know of nothing further , regarding the formation of similar
compounds to fuminates , derived from higher alcohols .

See attachment , " Notes and Correspondence" towards the bottom of the page .

It is possible that a propanol or butanol derived "quasi" fulminate of silver might be an interesting compound .

[Edited on 21-4-2007 by Rosco Bodine]

Attachment: Munroe's note concerning fulminates.pdf (273kB)
This file has been downloaded 1265 times

The_Davster - 21-4-2007 at 13:15

Fascinating, if he had someone researching these in 1911 there should be some data on them somewhere.

Rosco Bodine - 21-4-2007 at 13:25

Yeah one of the things I wondered about is if a double salt might form from the normal fulminate and a quasi-fulminate , if both were dissolved in ammonia and the
solution neutralized , as this might be a strategy for
taming silver fulminate .

A double salt might form in situ from a use of mixed alcohols .

Also other metals which do not form the normal fulminates , might possibly form a quasi-fulminate .
Copper for example , or other metals might do this .

[Edited on 21-4-2007 by Rosco Bodine]

ssdd - 21-4-2007 at 18:12

Ok so after looking up what metals may be alloyed with my silver supply I found the following.

When copper is added to a strong nitric acid the liquid turns a vivid green color. This happened when I added my silver to the nitric in my first attempt a few weeks ago. When copper is added to a weak acid solution it turns a pale blue color. This seems to be what happened when I used the 3 molar nitric.

So my guess would be that I have a fairly high copper content. Would this have much effect? If so, by what methods can I purify the silver?

The_Davster - 21-4-2007 at 18:23

Dissolve your impure silver in your dilute nitric acid, then add lots(to compensate for any excess acid) of copper metal to this. Silver powder/crystals will collect on the copper and can be removed from the copper without any force really. Then use that silver to make the SF, but using concentrated nitric acid.

ssdd - 22-4-2007 at 04:07

Ill have to give that a try sometime this week, thanks.

Hennig Brand - 1-6-2010 at 13:29

I have been messing around with Silver Fulminate quite a bit lately, very interesting material. I first made it about 3 years ago, but never got great yeilds(less than 0.5g from 1g silver). In the last few days I have been consistantly getting better yeilds, always over 0.75g and the last batch was 0.91g SF/1g Ag. At least with my materials there is a very small difference in temperature between forming SF and destroying SF. With my ethanol (homemade 90%) added acetone is a must, but how much is added is very important. I have found for a 1g silver batch, with 8mL 85% HNO3 and 8mL H2O, that 8mL ethanol 90%, and 2.5 mL acetone to be about optimal. Much less than this seems to sacrifice yeild, much more and the reaction is more violent and very difficult to keep from loosing your yeild to decomposition. For my materials and set-up, the reaction starts around 65C, with care(swirling and cold water bath the temperature is allowed to rise to 75C at most if possible, where a good bunch of white precipitate appears. Once you see that precipitate get that temperature below 70C with the cold water bath and swirling(I keep it around 65C for the rest of the reaction, although I feel the important part of the reaction is in those first 10 seconds anyway, the rest of the exothermic reaction taking place doesn' t seem to add anything to the yeild at all). In truth I feel the only thing gained from keeping the temp over 70C after the precipitate forms is decomposition of your hard won product.

This is what I have found to be workable for my material. I am aware that this synthesis is very sensitive to any changes, even small ones, even small differences in the amount and type of impurities in your alcohol-acetone, or small differences in how much water or nitric acid evaporated while heating. Every time I do this reaction it goes a little differently, and I think that I am doing it exactly the same(more or less).

Anyway 0.91g from a gram of silver is good as far as I am concerned. Liebig claimed to get about 1g from a gram of silver.

I have been turning most of my SF into bangsnaps using the old fashed method like in COPAE. Just put a little powder on the budgie gravel and wrap in tissue. Mine are about 100 times stronger though if there really is only 80 micrograms in the commercial ones.

I have tried to read everything I can get my hands on about silver fulminate, and most of it seems to either be blatantly wrong or very inadequate when describing a synthesis. In there defence it is a little like trying to learn how to throw a baseball by reading.

otonel - 8-4-2011 at 10:27

I have a 100ml solution of 10% silver nitrate and I want to make silver fulminate.
Can someone help me to calculate how much nitric acid and alcohol is necessaries to use for complete reaction.
Is my first try to make fulminates and I need your help and advice.

quicksilver - 8-4-2011 at 11:19

1st of all are you aware of that particular material's sensitivity? Have you done some background in researching it's appropriate handling, mfg, &, buffering?
2nd; using a silver nitrate solution is not not appropriate especially since the solution may be a water based solution....is it?

Contrabasso - 8-4-2011 at 12:47

Turning 100ml of solution into fulminate is madness, far too much for a first attempt.

otonel - 8-4-2011 at 13:36

Sorry I don`t explain correct, I have 100 ml silver nitrate but I don`t want to use all at on time.
For my first attempt I think 5 ml of solution is enough an relatives safe in case of accidental explosion

quicksilver - 8-4-2011 at 13:53

I don't want to repeat myself; however did you do your homework? Sensitivities, research, solvent, buffers?
ANY primary is much too serious to get into if there is a need to start at the bottom and silver fulminate is sensitive enough to make this a very brief conversation if there is little common knowledge.

otonel - 9-4-2011 at 07:13

Quicksilver I do my homework I know how sensitive is that fulminates and tomorrow I will try to make using my 10% solution 10 ml mixed with 10 ml 70%HNO3 heated and I will add 12 ml ethanol.
I think is good proportion of chemicals and I use 10% solution because if I boiled to make concentrated solution is hard for me to appreciate how concentrate is.
I ask for your help not for warnings, I have experience with another primaries and if I accomplish to make fulminate what is best option to keep that, is good to use kerosene or a nitrocellulose dissolved in acetone

quicksilver - 9-4-2011 at 08:15

If you answer my questions, I'll answer yours. My purpose is to maintain an element of safety.

Where did you hear about combining a fulminate in nitrocellulose lacquer?

Do you understand that silver fulminate is still extremely sensitive within a fluid?

Where have you been getting your source material from?

otonel - 9-4-2011 at 13:53

Quote: Originally posted by quicksilver

1st of all are you aware of that particular material's sensitivity? Have you done some background in researching it's appropriate handling, mfg, &, buffering?
2nd; using a silver nitrate solution is not not appropriate especially since the solution may be a water based solution....is it?

I answer of your question:
1. I m aware of silver fulminate sensitivity, I read a lot of chemistry articles and homemade explosives about that explosive
2. I want to use my 10% solution because if I boiled to make concentrated solution is hard for me to appreciate how concentrate is.

Where did you hear about combining a fulminate in nitrocellulose lacquer?
That was just my idea

Do you understand that silver fulminate is still extremely sensitive within a fluid?
I understand and I search a way to decrease friction and impact sensitivity I read somewhere about military uses of silver fulminate in special detonators and I think is a method to reduce that sensitive

Where have you been getting your source material from?
I bought silver nitrate solution from a pharmacy

Another question please?

quicksilver - 10-4-2011 at 05:51

There are very few EFFECTIVE & reliable methods to deal with the sensitivity issue. It will continue to be notoriously vicious even with a buffering concept (use of dextrin) that was an early 1920's technique the pyrotechnics industry toyed with when making "snap caps" (throw down toys for sidewalk impact). I have never heard of a commercial usage for silver fulminate as it presents all the problems inherent in a material with it's level of sensitivity (static, friction, impact, etc) and no remarkable benefits. Mostly it has been left alone after the attempts to buffer and use a feather to manipulate was deemed impracticable even for the toy fireworks industry. (see AFN article on fulminate from "Collections").

Hennig Brand - 23-5-2011 at 12:21

I used to cut the tip of a soft plastic straw into a small scoop and use that to measure out ~8mg for individual bang snaps, which worked well. I loaded several hundred by this method in a short period of time a while back without incident.

I have tried Silver Fulminate mixed with Nitrocellulose lacquer to make explosive heads for electric igniters (squibs?), which worked very well. I only stored them for a couple of weeks or so, so I'm not really sure about long term storage stability of these explosive igniters.

I have always found that the reports of extreme sensitivity were overblown, however I have not done a thorough study, and there could exist special conditions that could lead to extreme sensitivity (I don't know for sure). I also imagine the high cost of Silver was a huge deterent to its use as it was with other primaries using Silver.

I tend to avoid it as an initiator mostly because there are other, more well known primaries that have been tested and proven to be effective and safe (relatively). I always keep it in the back of my mind though, as it has excellent initiating abilities in small quantities, is very storage stable, and uses very common chemicals for its synthesis.

[Edited on 23-5-2011 by Hennig Brand]

quicksilver - 24-5-2011 at 05:34

Quote: Originally posted by Hennig Brand

I have always found that the reports of extreme sensitivity were overblown, however I have not done a thorough study, and there could exist special conditions that could lead to extreme sensitivity (I don't know for sure). I also imagine the high cost of Silver was a huge deterent to its use as it was with other primaries using Silver.

Frankly, I found it to be really uniquely sensitive. Perhaps within NC lacquer (and thinned enough) it could be contained for a period of time but remember fulminates' big problem was their shelf-life if exposed to temperature at and above 40C.
Simply from an empirical standpoint, I found it potentially nightmarish if weights above a gram were employed. I believe at that weight it becomes a fairly dependable "finger-eraser".
No exaggeration: I have some serious respect for it. I also agree that it also was the base metal that had additional impact on it's usage.

The WiZard is In - 24-5-2011 at 06:07

Quote: Originally posted by quicksilver

Frankly, I found it to be really uniquely sensitive. Perhaps within NC lacquer (and thinned enough) it could be contained for a period of time but remember fulminates' big problem was their shelf-life if exposed to temperature at and above 40C.

Simply from an empirical standpoint, I found it potentially nightmarish if weights above a gram were employed. I believe at that weight it becomes a fairly dependable "finger-eraser".
No exaggeration: I have some serious respect for it. I also agree that it also was the base metal that had additional impact on it's
usage.

I found it to be really uniquely sensitive. Et tu!?

The Philadelphia medical museum, Volume 1. 1805
Edited by John Redman Coxe

Professor Veau-de-Launay, in a letter to J. C. Delametherie, gives the following
account of an accident with fulminating silver, in his laboratory.

" I had employed one of my pupils, a very good operator, to prepare a small
quantity of fulminating silver, which he executed with skill.

The quantity obtained was about five grains, or a quarter of a gramme: it was
deposited in a crystal capsule, about two lines in thickness. He had taken a small
quantity, about half a grain, which was separated with a card, and then dried, and
afterwards detonated by slight friction. Next day, that is td fay 24 hours after the
preparation, this young person was desirous of taking an equal quantity from the
capsule to repeat the experiment, but he had scarcely touched the preparation with
the corner of a card, when a violent detonation and explosion took place in the
capsule, which was shattered into a thousand pieces. His face was covered with the
vaporised preparation, which was almost black, and adhered strongly to the skin ; his
eyes experienced a strong shock, which produced extreme pain; the opaque cornea
became red and inflamed. Happily his fear was the greatest evil : by washing and
bathing his eyes and face frequently with cold water, the effects of the detonation
were soon dissipated.

Fortunately, none of the fragments of the glass had touched his eyes or his face; they
were thrown nearly in a horizontal direction, to a considerable distance : some were
thrown upwards of 12 feet.

Nickelson’s Journal

---
Minutes of Proceedings of The Institution of Civil Engineers: with
other Selected and Abstracted Papers Vol. LXI London 1880

ABEL ON EXPLOSIVE AGENTS.

[Minutes of 23 March, 1880].
WILLIAM HENRY BARLOW, F.R.S., President, in the Chair.
(Paper No. 1712.)

" Explosive Agents applied to Industrial Purposes."

By FREDERIC AUGUSTUS ABEL, C.B., F.R.S., Assoc. Inst. C.E., Past
President C. S. and Soc. Tel. Engrs., President of the Institute of
Chemistry, &c.

[Attached]

Silver fulminate was employed for the purpose of instituting more
precise experiments than could be made, in operating on a larger
scale with gun cotton, on the influence of the material com¬posing
the tubes, on the condition of their inner surfaces, and of other
variable circumstances, on the transmission of detoriation. Half a
grain of fulminate, freely exposed and ignited by a heated body,
will transmit detonation to some of the compound placed 3 inches
from it, but does not do so with certainty at a distance of 4 inches.
But when that quantity of the fulminate is inserted into one end of
a stout glass tube 0.5 inch in diameter, and 3 feet long, its
detonation is invariably induced by that of a similar quantity of the
fulminate placed inside the other extremity of the tube. This result
is uncertain when the length of tubes, of the same thickness and
diameter, exceeds 3 feet 3 inches. Glass tubes transmitted the
detonation more rapidly than tubes of several other materials of
the same diameter and thickness of substance. Thus, with the
employment of double the quantity of fulminate required to
transmit the detona¬tion with certainty through a glass tube of the
kind described, 3 feet in length, it was only possible to obtain a
similar result through a pewter tube 31.5 inches long, a brass tube
23.7 inches long, an India rubber tube 15 8 inches long, and a
paper tube 11.8 inches long. The difference, in the results was not
ascribable to a difference in the escape of force on the instant of
detonation, in consequence of the fracture of the tube, nor to the
expenditure of force in work done upon the tube at the seat of
detonation; since the glass tubes were always destroyed by the
first explosion to a greater distance along their length than any
other, and the brass tubes, which were in no way injured at the
seat of the explosion, did not transmit detonation to so great a
distance as the pewter tubes, which were always deeply indented.
The transmission of detonation appeared also not to be favoured
by the sonorosity or the pitch of the tube employed, as the
sono¬rous brass tube did not favour the transmission to the same
extent as the pewter tube. Moreover the transmission of
detonation [90] by the glass tubes was not affected by coating
them with several layers of paper, or by encasing them in tightly
fitting India rubber tubes. These differences appeared, on further
investigation, to be ascribable not to any important extent to the
difference in the nature of the material composing the tubes, but
simply, or at any rate chiefly, to differences in the condition of the
inner surfaces of the tubes. Thus, brass tubes, the inner surfaces
of which were highly polished, and paper tubes when coated inside
with highly glazed paper, transmitted the detonation of the silver
fulminate to about the same distance as the glass tubes. On the
other hand, when the inner surfaces of the latter were slightly.
roughened by coating them with a film of fine powder, such as
French chalk, they no longer transmitted detonation to the distance
which they did before. Other slight obstacles to the unimpeded
passage of the gas wave through the tubes greatly reduced the
facility with which detonation could be transmitted by means of
tubes. Thus, when a diaphragm of thin paper was inserted about
halfway into the glass tube, detonation was not transmitted, even
with the employment of about six times the quantity of fulminate
that gave the result with certainty under ordinary conditions.
Similarly the transmission of detonation by increased charges of
mercuric fulminate and of gun cotton was prevented by the
introduction into the tubes of light tufts of carded cotton wool, just
sufficient in quantity to shut out the light when looking through the
tubes.

Attachment: Explosives Able on Explosive Agents II.doc (192kB)
This file has been downloaded 884 times

-------------
The First Chemical Achievements and Publications by Justus von Liebig
(1803-1873) on Metal Fulminates and Some Further Developments in Metal
Fulminates and Related Areas of Chemistry
Wolfgang Beck

PDF
Attachment: silver fulminate.pdf (349kB)
This file has been downloaded 1088 times

djh
----
The paradox of the fall of the Shah,” Mr.
Milani says, “lies in the strange reality
that nearly all advocates of modernity
formed an alliance against the Shah and
chose as their leader the biggest foe of
modernity.” The Iranians have already
paid dearly for this folly. What price the
rest of the world will pay remains an
open question.

John Muravchik
Wall Street Journal 19I11
Review of : Abbas Milani - A Monarch Dethroned
Palgrave Mcmillian

quicksilver - 24-5-2011 at 09:45

For many years you've always gotten some of the better written material on energetic chemistry & pyrotechnics. I only wish that folks would "cut & paste" more of the contributions. The material from Britain & "ABEL ON EXPLOSIVE AGENTS." are particularly unique.
Just my opinion of course, but since the UK's 7/7 tragedy, there has been less and less public domain reading on those subjects (within & from the UK).

The WiZard is In - 24-5-2011 at 11:58

Quote: Originally posted by quicksilver

Simply from an empirical standpoint, I found it potentially nightmarish if weights above a gram were employed. I believe at that weight it becomes a fairly dependable "finger-eraser".
No exaggeration: I have some serious respect for it. I also agree that it also was the base metal that had additional impact on it's usage.

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djh
----
Yes! there are books that
I own you cannot DL from
Google Books.

Hennig Brand - 23-6-2011 at 12:48

I am not sure we are all talking about the same chemical here. For instance this story posted by The Wizard (very interesting though by the way), has the opening,

" I had employed one of my pupils, a very good operator, to prepare a small
quantity of fulminating silver, which he executed with skill.

Now Fulminating Silver is normally another name for Silver Nitride (Ag3N), which is a very different animal than Fulminate of Silver (AgCNO) or Silver Fulminate, which is what it is normally called. I don't have any experience with Silver Nitride but from watching videos and reading it seems like it is many times more sensitive than Silver Fulminate, and with very little utility.

The two names are so often mixed up that it leads to a lot of confusion.

I usually make less than a gram at a time of Silver Fulminate. A gram will make a hundred or so fairly strong bang snaps, (each one being able to make your ears ring if used indoors). I wouldn't handle it in large quantities.

The price of silver is sort of depressing, if only I had invested.

The WiZard is In - 23-6-2011 at 13:33

Quote: Originally posted by quicksilver

There are very few EFFECTIVE & reliable methods to deal with the sensitivity issue. It will continue to be notoriously vicious even with a buffering concept (use of dextrin) that was an early 1920's technique the pyrotechnics industry toyed with when making "snap caps" (throw down toys for sidewalk impact). I have never heard of a commercial usage for silver fulminate as it presents all the problems inherent in a material with it's level of sensitivity (static, friction, impact, etc) and no remarkable benefits. Mostly it has been left alone after the attempts to buffer and use a feather to manipulate was deemed impracticable even for the toy fireworks industry. (see AFN article on fulminate from "Collections").

Chemical experiments
By George William Francis
London 1842
Google.com/books
Book has been republished.
I beleive there was an American edition.

1535. Put a minute quantity of one of the fulminates along with a little glass dust on
a stone, and rub it with the face of a hammer, immediate explosion will ensue. This
fact occasions the fulminate of silver obtained by the above process to be used for
Waterloo crackers and other similar objects of amusement.

1536. To make Waterloo crackers.—Take 2 slips of stiff paper or card-board about |
of an inch wide, and 4 or 5 inches long each ; lay a mixture of powdered glass and
gum water over one end of each paper for about an inch in length, let this dry, and
then put 1/4 or an 8th part of a grain of fulminating silver upon the glass on one piece
of the paper ; place the other piece of paper upon this, so that the glass upon the
one shall rest upon the glass of the other, and the free ends of both papers be
outwards. Paste a piece of thin paper over the whole covered parts, to attach them
to each other. Upon pulling the outward ends of the papers, the two surfaces of glass
will grind upon each other, and occasion the explosion of the fulminating silver.
When these crackers are made of a larger size, with a grain or more of fulminate, they
are used as attachments to a door and doorpost, so that if any one should enter at
night, the explosion of the composition may indicate the opening of the door.

1537. Put the amount of about as much as a mustard seed of fulminating silver
into a pair of snuffers when quite cold ; upon snuffing the candle, it will explode.

1538. Put the same quantity on to a piece of paper pasted over, and while the
paste is wet, fasten it with paper all round the head of a pin ; stick the pin thus
charged in the wick of a candle. When the tallow shall have burnt away down to the
pin, the fulminating silver will explode and put out the candle. Let it be remembered,
that with this and similar experiments the grease is always scattered.

1539. Put 1/4 of a grain in a piece of tinfoil, put it then at the bottom side of a
drawer, and on opening or shutting the drawer, the powder will explode.

1540. Mix the same quantity with glass powder or sand, to which a little weak gum
water has been added. Wrap a little of this mixture in a small piece of thin paper.
When dry, throw the ball thus formed with some force against the floor or other hard
substance, and detonation will be the result.

1541. If one of these balls be put under the leg of a chair, it will go off when any
one sits down in the chair.

1542. As a cheaper material for the above purpose, the ammoniuret of mercury
may be used ; it is prepared by dissolving the protoxyde of mercury in ammonia, and
is nearly as explosive as the ammoniurets of the noble metals, gold, silver, &c. These
fulminates should always be kept under water, for when dry, even the falling of them
into a phial, or the taking them up with a piece of paper, or the point of a knife may
occasion a most terrific explosion.

djh
---
It is essential that persons having explosive
substances under their charge should never
lose sight of the conviction that, preventive
measures should always be prescribed
on the hypothesis of an explosion.

Marcellin Berthelot - 1892
Explosives and their power - Page 47

The WiZard is In - 23-6-2011 at 13:38

The Boston journal of philosophy and the arts, Volume 3
1826
ART. XV.—On some Kinds of Fulminating Powder inflammable by Percussion, and their
Use in Fire-arms. By P. W. Schmidt, Lieutenant in the Prussian service.* (Philos. Mig.)
Google.com/books

A POWDER inflammable by percussion, has been used for some years past, especially in
fowling-pieces. The following formula: have been given for the preparation of this
powder, the principal ingredient of which is chlorate of potash.
1. 100 parts of chlorate of potash (fulminating salt,) 12 parts of sulphur, and 10 parts
of charcoal are closely mixed. The grains are produced by forcing the soft paste
through a sieve.
2. 100 parts of chlorate of potash, 42 parts of saltpetre, 36 parts of sulphur, and 14
parts of lycopodium.

These are the usual ingredients that have hitherto been mixed with the chlorate of
potash for the purpose of making priming powder. The guns, however, with which
this powder is used, are very various in their construction. In some it explodes of
itself by means of the mechanism of the lock, on being cocked, into a small conical
recess, which communicates with the touch-hole, in others, it is put in previous to
every shot. In the former kind of guns a quantity of powder sufficient for a certain
number of shots is kept in a recess attached to the lock, called a magazine; and the
locks (which were invented in England by Mr Forsyth) are called maginine locks.

In some guns the stroke of the cock, which is in the shape of a hammer, falls
immediately on the fulminating powder strewed in the above recess. In order to
protect the powder from wet, small balls of it were covered over with wax, and
placed sometimes in the conical recess, and at others fixed lo the cock itself. In both
instances the ball was kindled in the recess just mentioned, by means of the
percussion.

Besides these, other contrivances have been used for the purpose of igniting this kind
of powder; yet they have all their defects, and offer so many difficulties in practice as
to have prevented their general introduction.

Latterly, they have contrived in Germany to fix the powder in a small case of very thin
copper foil, for the purpose of keeping it dry ; and for that purpose a cylinder is
screwed into the body of the gun instead of the touch-hole, and

From Schweigger's Journal, Band xi. p. 66.

rests for the sake of greater support on the plate of the lock, instead of resting on the
pan. The inner space of the cylinder is filled in loading with the same powder as that
of the shot. The igniting box, at the bottom of which is the detonating powder, is,
previous to firing, upturned on the cylinder. In this cylinder is a small round aperture
leading to the inner space of the cylinder. On the trigger being pulled, the cock strikes
the igniting box, and the fulminating powder is kindled by the blow, flows through
the aperture, inflames the shot, and breaks the igniting-box.

Mr Wright seems to have taken great pains with the subject.* He recommends, for
the firing cases, to use fulminating mercury, saying that sportsmen had justly
complained of the powder made of chlorate of potash, since it soon produces the
oxidation of the barrel and touch-hole, and the charcoal which remains after the
firing, rendering them unfit for use. The advantages of his new powder he
enumerates as follows: It does not make the gun rusty so soon as the other; it
produces neither dirt nor moisture; it is not liable to explode as the other powder,
and if it does explode its effects arc less destructive, inasmuch as its power does not
extend so far.

The following is his mode of preparation:
" I place two drachms of quicksilver in a Florence flask, and pour six drachms
(measure) of pure nitric acid on the mercury; this I place in a stand over a spirit-lamp,
and make it boil till the quicksilver is taken up by the acid ; when nearly cool, I pour it
on an ounce (measure) of alcohol in another flask: sometimes immediate
effervescence ensues, with the extrication of nitrous aether; and often I have been
obliged to place the mixture over the lamp, till a white fume begins to rise, when the
effervescence follows. I suffer the process to continue (removing the lamp) till the
fumes assume a reddish hue; when I pour water into the flask, and the powder is
found precipitated to the bottom, 1 pour off and add fresh water, permitting the
powder to subside each time before the water is pourea off, so as to free the
substance as much as possible from the acid, and then I pour it on a piece of filtering
paper, and place the powder in an airy room to dry. It should be kept in a corked (not
stoppered) bottle."

For the filling of the cups, he makes use of an ivory pin, which has a scoop at one end
for the purpose of receiving

* Mr Wright's paper will be found in Phil. Mag. vol. Ixii, p. 203. Bos. Jour. JVOT. £ Dec.
1825. 18

the powder, and at the other is cut flat. With it he puts in as much fulminating
mercury as will cover the bottom; he then dips the flat end into a strong tincture of
benzoin, and rubs this substance gently about the case; by which means the powder
is set fast and covered as with a varnish.

Professor Schweigger, speaking of these kinds of experiments in his chemical lectures,
observed on the practicability of kindling gunpowder by the admixture of other
substances, as has been shown in a criminal investigation that took place at Munich a
few years ago. A box filled with gunpowder was sent to an individual provided with
fulminating papers, which were to inflame on the box being opened. Fortunately,
however, the murderous design was frustrated ; for although the papers exploded,
they did not kindle the powder. The assassin was discovered and punished. M.
Gehlen, who had been examined at the trial, was led by the circumstance to make
several experiments for the purpose of kindling gunpowder by means of Brugnatclli's
fulminating silver, but they all failed.

It seems that in England, too, difficulties had been found in igniting gunpowder with
fulminating mercury; for Mr Wright observes, " if any one doubts the practicability of
firing gunpowder by means of fulminating mercury, by procuring a percussion-gun, he
may try the experiment and be fully satisfied."

Professor Schweigger having, therefore, requested me to try some experiments on
this subject, especially with fulminating silver, I made them in the chemical laboratory
of our university, and the following were the results.

I. Fulminating silver was prepared in the usual way ; five drachms of fuming nitric
acid, and five of alcohol were poured over one drachm of fused nitrate of silver.
When the effervescence and solution were complete, water was added. The
precipitate of fulminating silver was filtered off, and all the remaining acidity washed
from it with water. The liquid which had passed through the filter gave with muriatic
acid a copious precipitate of chloride of silver. The fulminating silver, which was of a
whitish tint, was now subjected to the following experiments :

1. When damp it ignited very rarely, and only by a strong blow. When dry, it explodes
easily, and with a much slighter blow.
2. When touched with sulphuric acid, it exploded equally strongly, whether damp or
dry.
3. Damp or dry, it exploded in the fire.
4. The substance which remained after the ignition, was of a bluish brilliant hue and
a disagreeable metallic taste. I could gather but little, which, dissolved in water,
produced a faint red tint on litmus paper.
5. I failed in several attempts to ignite gun-powder with the fulminating silver. I
therefore put quantities of the size of a small pin's head, into some copper boxes,
fastening it in some with tincture of benzoin, in others with a solution of gum arabic
in water; and others I tried to press on the bottom without any other aid. I applied
them to guns prepared for the use of igniting-boxes, and thus kindled the gunpowder
with incredible swiftness. The series of experiments thus made in the presence of
Professor Schweigger, leave no doubt that fulminating silver will easily ignite gun-
powder in a mannner that will secure it against a rapid dispersion on exploding.

II. The fulminating mercury was prepared in the manner prescribed by Mr Wright. But
I must observe that the experiment only succeeded by the application of fuming nitric
acid. The fulminating mercury, when obtained, was washed till every particle of
acidity had disappeared from it. It was then submitted to the following experiments :
1. When dry, it exploded like fulminating silver, and with a much slighter blow than
required for the powder made of chlorate of potash. Thus it would appear as if the
fulminating quicksilver had not in this respect the advantage over the igniting powder
made with the salt just named.
2. When perfectly dry only, it could be ignited with sulphuric acid.
3. In the fire it exploded, both wet and dry.
4. The substance remaining after the explosion, had a bluish brilliant tint and a bitter
acid metallic taste. With a small quantity dissolved in water, litmus paper was slightly
reddened. I made no further investigation, inasmuch as the examination of the acids
of fulminating metals, before and after the explosion, was not my object; especially
since Dr Liebig has lately published a series of very interesting experiments, the
repetition of which would require very extensive labour.* Liebig calls those acids
fulminic acids, which

* Vide Ann. it Chim. et it Phys. part xxiv. p. 294, or the translation in Gilbert's Annalen
ier Phys. part Ixxv. p. 393—422.

Mr Liebig found that Brngnatclli's detonating silver was dissolved in lime-water or
solutions of the caustic alkalies, whereby being the property of all metals, he
distinguishes into silver and mercury fulminic acids, &.c.

The great advantages, however, of the fulminating quicksilver as igniting powder,
extolled by Mr Wright, I did not find confirmed; although l proceeded to fill copper
boxes, as I had done with the detonating silver, which all ignited the charge.
III. I also submitted to experiment the first-named mixture, principally consisting of
chlorate of potash ; and found

1. That it exploded only by a hard blow. Its efiicts were much less than those of the
detonating silver or quicksilver. Mr Wright, indeed, says the contrary of the latter; it
seems, therefore, that I used a better kind of fulminating mercury ; but for that very
reason I must give the chlorate of potash the preference for practical use.

2. In the fire it pufled away like gunpowder.

3. The substance remaining after the explosion is blackish and dusty, and contains
less of acidity than that left by the quicksilver. Thus, and indeed from all my
experiments, it is evident that it oxidizes the iron less than the fulminating mercury.
Moisture is also left by the latter; and the charcoal left by the mixture of chlorate of
potash, after kindling a copper box filled with it, is very unimportant:—therefore this
mixture is preferable as an igniting powder. This is also the reason why the
manufacturers no longer use the fulminating quicksilver. I know one who makes and
fills weekly several thousands of copper caps, for which he uses the chlorate 31,25
per cent of oxide of silver was deposited. They produce peculiar salts, called
fulmiiuttts, which explode with great violence. These salts are dissolved l.iy nitric acid,
sulphuric acid, and acetic acid ; the silver fulminic acid contained in them, and so
difficult to be dissolved, is deposited; and by heating a solution of fulminate of lime
to the boiling point, and adding a moderate quantity of nitric, acid is deposited, on
cooling, at the bottom of the vessel, in the shape of long white crystals. This acid may
be easily dissolved in boiling w ater ; from which it crystallizes again in cooling, has a
disgusting metallic taste, and reddens litmus paper. But it cannot subsist of itself
without combination with a metal; and m the same manneras there are prussic acids
of iron, copper, silver, and gold, so the fulminic acid combines with silver, quicksilver,
copper, iron, zinc, ice, into proper fulminic acid, which again form different
combinations with the bases, e. ir. potash, soda, barytes, strontian, lime, &c. Thus,
for instance, silver-fulminate of potash consists of 35,03 parts of silver-fulminic acid
and 14,ir2 of potash ; silver-fulminate of soda, of 88,6ti parts of silver-fulminic acid
ar.d 11,34 of alkali. When cooling, Berthollet's detonating silver forms granular
shining white crystals. One part of this salt makes as violent a report as three parts of
Howard's (Bru^natelli's) fulminating silver With magnesia the silver-fulminic acid
combines in two ways. One combination is a simple decrepitating, not detonating,
insoluble powder, of a rosy tint; the other forms white capillary crystals, and
explodes very loudly. The first combination was used for the analysis of fulmic acid in
the dry way ; in which the fulminating silver was evinced to consist of 32,22 of
oxygen, 3,22 of hydrogen, 11,28 of azote, 9,68 of carbon, and 41 of silver. mixture, the
preparation of which is both less expensive and less dangerous than that of the
fulminating quicksilver. There is another circumstance attending this mixture. In filling
the caps, it will sometimes happen that the quantity put in is doubled, which I find is
of no injurious consequence with this mixture; but might endanger the person firing
with the fulminating mercury, as the box will burst too violently.

With respect to the power of igniting the charge, the different kinds of powder whLh I
have compared are equally effectual.

IV. I submitted the mixture of chlorate of potash mentioned above to the following
experiments.
1. That part only ignited which was struck, without igniting that lying around it.
2. In the fire it burns away with noise.
3. I placed it in the usual way in copper caps, but could not ignite a charge with them.
The cause of this may be explained by the construction of the locks, with reference to
the properties of this detonating powder. That part of the cap situated just above the
opening of the cylinder remains, as the blow cannot fall on it unignited, as shown by
the experiment No. 1. But the communication of the ignited part with the charge, is
prevented by the manner in which the cock strikes the cap. In guns in which such
powder is used for igniting, it lies as above stated, in small balls in a conical aperture.
Here it is nearly all ignited by the striking of the cock, and must of necessity flow
inwards, every other way of escape being shut up.

In conclusion:—I have to add that the method of filling the caps recommended by Mr
Wright is not only laborious, but even dangerous. How are manufacturers to employ
that method when they have to fill several thousands a week ? I have made various
trials, and the following process seems to me to be the best.
Pour some adhesive solution or tincture over the powder, and mix it into a stiff kind
of liquid. Take with a brush or a stick a large drop of it, and apply it against the
bottom of the cap.

This method is both quick and free from danger; whilst on filling with the dry
detonating powder, the least careless touch may produce an explosion.

In order to prevent the corrosion of the cylinder, and its becoming useless by the
formation of sulphuret of iron (an evil very common with iron touch-holes, and
caused more by the action of the gun-powder than by that of the igniting substance),
the inside of the cylinder should be lined with a metal which will neither oxidate nor
easily combine with the ingredients of the powder.

...who accidentally trod on a quantity of fulminating silver

The WiZard is In - 23-6-2011 at 13:48

had his foot nearly destroyed by the explosion.

The American journal of science, & c, Volume 1. 1818.
ART. XVI. Cautions regarding Fulminating Powders. Fulminating Mercury.
Google.com/books

DURING a late lecture in the laboratory of Yale College, a quantity of fulminating
mercury, probably about 100 or 150 grains, lay upon a paper, the paper lay on a
small stool, which was made of pine plank, one inch and a half thick; a glass gas
receiver, 5 or 6 quarts capacity, stood over the powder, as a guard, but without
touching it, and stool and all stood on one of the shelves of the pneumatic
cistern, surrounded by tall tubes and other glasses, several of which were within
6 or 8 inches. A small quantity of the fulminating powder, at the distance of a few
feet, was merely flashed, by a coal of fire, but without explosion. In a manner,
not easily understood, the whole quantity of powder under the large glass
instantly exploded with an astounding report; but the glass was not exploded—it
was merely thrown up a little : in its fall it was shattered, and broke a glass which
it hit, but no fragment was projected, and none of the other contiguous tubes and
glasses were even overset, nor were any of a large audience, and some of them
very near, even scratched; but the plank, one and a half inch thick, on which the
powder lay, had a hole blown quite through, almost as large as the palm of one's
hand. This is a striking instance to prove that the initial force of this powder,
when exploded, is very great, but that it extends but a very little way. If it be
strewed through a glass tube of three-fourths of an inch in diameter, and
exploded by a coal of fire or hot iron, the tube may be held in the naked hand,
and the powder only flashes without breaking the tube, and merely coats it over
inside, and that very prettily, with the revived quicksilver.

Fulminating Silver.
Chemists are too well acquainted with the tremendous energy of this
preparation, to make any comment upon its powers necessary. Unhappily,
however, it is now made a subject of amusement; it is prepared for sale by those
who know nothing of it, except as a nostrum, and it is bought by others who have
not even this degree of knowledge. It is true it is put up in small quantities, in the
little toys called torpedoes, and, if exploded one by one, they will ordinarily do no
harm ; but as they fall into the hands of children, we can never be secure that
they will be discreetly used.

A very severe accident, from the unexpected explosion of this substance,
occurred some years since in the laboratory of Yale College. (See Bruce's
Journal, Vol. I. p. 163.) And, notwithstanding that this occurrence was well known
in New Haven, the same accident, only under a severer form, has again
occurred in that town.

A man who had bought the secret of making fulminating silver, had prepared
as much as resulted from the solution of one ounce and a half. Apparently, in a
great measure, unaware of the nature of the preparation, he had placed it,
unmixed with any thing, on an earthen plate, which stood on a table ; his wife
and children being around, he sat down to distribute the powder upon several
papers which he had prepared for the purpose; Band and shot are mixed with
the powder in the papers for the purpose of giving momentum, and of producing
attrition when the torpedo is thrown, in order to ensure its explosion. Probably
also the sand, looking not very unlike the powder, may be intended to screen it
from view, and thus to preserve the secret, should the papers be opened. The
unhappy man no sooner touched the fulminating silver with a knife, than it
exploded with its nsual violence ; the table was split in two ; blood issued
copiously from every part of hit face, not from wounds, for it does not appear
that the fragments hit him, but, according to the opinion of a competent judge,
the blood was actually forced through the pores of the skin by the power of the
explosion, which very nearly destroyed his eyes. He suffered immensely, but
now, at the end of eight months, sees partially with one eye, but the other is
nearly, if not quite, destroyed.

Should not the tampering with such dangerous substances by ignorant people be
prevented by law ? . .

In a late lecture in the laboratory of Yale College, some fulminating silver, on
the point of a knife, was in the act of being put upon a copper-plate connected
with one pole of a galvanic battery in active operation, the other pole was not
touched by the experimenter : but it seems that the influence which was
communicated through the floor of the room was sufficient instantly to explode
the powder, as soon as the knife touched the copper-plate ; the knifeblade was
broken in two and one half of it thrown to a distance among the audience.
Recently also, we are informed, in one of the foreign journals, that a man in
England, who accidentally trod on a quantity of fulminating silver, had his foot
nearly destroyed by the explosion.

djh
---
For fools rush in where
angels fear to tread.

Alexander Pope
An Essay on Criticism
1711

Hennig Brand - 24-6-2011 at 16:18

You always find some very interesting things to read. I agree that Silver Fulminate is some pretty dangerous stuff, however it would be even easier to make the case, by referring to the literature, that nitroglycerine is far too dangerous to handle. Most people who have worked with nitroglycerine find that it is not the boogeyman that it is so often made out to be, and that the dangers are easily managed if one has half a brain. I am not suggesting that silver fulminate and nitroglycerine are the same.

In the last two days I have done about 8 syntheses of Silver Fulminate. What I found by just playing with the quantities and type of reagents was kind of interesting. The biggest reason I was having trouble with decomposition during my prior attemps was because of too much HNO3. I also discovered that it was possible to get good results with just ethanol and no acetone at all.

Here are a few pictures of one of the last processes. The silver used was sterling silver wire from a crafts shop which cost about $1.38 per gram. Sterling silver is only 92.5% silver I believe. A half gram of the metal was used for each reaction.

Reagents:

5mL 65% HNO3
2mL deionized water
0.5g sterling silver
6mL+ 90-95% ethanol

Procedure:

The whole reaction was done outside.
Silver is weighed and cut into short sections with nippers before being put in a 50mL beaker. The 5mL of HNO3 and 2mL of deionized water are added to the same beaker. The beaker is placed on a hotplate on low heat to help dissolve the silver (red gas can be seen escaping from the beaker, do not breath in).

A green solution (from copper in sterling silver) can be seen after the silver has all dissolved. Take the beaker off the heat and pour the contents into a larger beaker ( the first time I didn't use a larger beaker and it boiled over ruining the reaction and making a mess). While still warm add 6mL of ethanol all at once. The reaction may start on its own, but usually needs to be placed back on the heat (small bubbles can be seen forming at the start of the reaction after a minute or two of gentle heating). IIRC the reaction starts somewhere around 60C. Once the reaction starts the beaker can be taken off the heat as the reaction generates its own heat and is self sustaining. Small amounts ~1mL of ethanol are added a couple to a few times to moderate the reaction rate and to make up for evaporative losses during the reaction.

The whole reaction takes around 5-10 minutes.
Gentle supplemental heating can be applied near the end of the reaction to drive it more to completion, however most of the reaction is done I believe at this point anyway.

At the end of the reaction the reaction mixture is diluted well with deionized water, the precipitate filtered out and rinsed repeatedly with more deionized water before being allowed to air dry.

Three different types of ethanol were used, 95% absolute ethanol, 95% denatured, and my own homemade which measures as 90% with a hydrometer. The absolute seemed to give the best results with 0.49g of silver fulminate from 0.5 gram of sterling silver. The denatured and homemade both gave between 0.4 and 0.45g.

With the smaller quantity and lower concentration of HNO3 in the reaction mixture the reaction was very easy to control. When the reaction got too violent and hot a little more ethanol was added which helped to dilute and cool the reaction. The volume of the reaction mixture was also kept from getting too low from evaporation by adding a mL or so of ethanol from time to time. Initially 6mL of ethanol was added all at once at the beginning before the start of the reaction.

In the last picture is the damp yeilds from the last two syntheses, once completely dry the clumps just fall into a pile of loose powder.

[Edited on 25-6-2011 by Hennig Brand]

Hennig Brand - 30-6-2011 at 11:00

Just to see what would happen I took the extra 5 minutes and used gently heating to drive the silver fulminate reaction more to completion. I got a yield of 0.57g from 0.5g of sterling silver, and I am pretty sure I could have gotten more if I was more patient. The first picture shows the yield on the scales.

The larger beaker in the picture above is a 400mL beaker, which I tilt slightly so the small volume reaction mixture sits in the bottom corner. To apply gentle heating the beaker is held above the hotplate an inch or two, while the hotplate is on fairly low heat (position 2 out of 7).

I also dug out an old sample of silver fulminate which is about 2 years old. It was kept at ordinary room temperatures, and in a dark container out of light. As you can see it has gotten quite a bit darker in color. I find the freshly made stuff has a little bit more zing in bang snaps, but the old stuff still works pretty damn well. The difference probably wouldn't be noticable unless compared one after the other. My testing methods are very primitive, but I can say it hasn't lost its main qualities. I suppose I could do some simple witness plate type testing or something.

[Edited on 1-7-2011 by Hennig Brand]

quicksilver - 30-6-2011 at 11:32

The color change looks fairly obvious even with the golden "over-hue" of the surrounding picture. - That the only intervening factor appears to be time (no UV, etc) IS odd. But then silver salts may change in very subtle temp or moisture situations. I have seen Ag azide alter a bit from mild temp.

I really don't know of a way to test for energetic characteristics without old-time mechanisms such as a miniaturized pendulum, etc. A witness plate would have to be miniaturized to a point where visual differences would be tough to distinguish. If there was a method to make a scale that fixed at a peak of driven energy that may work. But it would have to survive shock that might damage any device of sensitivity.

Rosco Bodine - 30-6-2011 at 13:33

Ooooh oooooh the supernatant sure is a pretty baby blue

http://www.youtube.com/watch?v=TkA7xQb6uPk Badfinger - Baby Blue

Hennig Brand - 30-6-2011 at 19:02

If a person could keep their sensitive body parts out of harms way, a small amount could be pressed into a small paper or soft plastic tube. Witness plate tests are performed with blasting caps, so make a small cap out of each silver fulminate sample (more than one of each would even be better). Try to keep everything as much the same for both caps as possible (use as much precision as possible). Do you think that might work?

As long as I kept the sensitive parts of my anatomy out of the way, and used casings that wouldn't create shrapnel in the event of a premature detonation, I wouldn't mind pressing a little silver fulminate.

The dark color is kind of an odd thing. Every sample I have kept around has gone dark, the more light its exposed to the quicker the darkening though.

That copper nitrate blue is very pretty, isn't it? Apparently the copper nitrate in the concentrated solution makes a greenish solution, but after dilution with alcohol and/or water it changes to that nice blue color.
Rosco and Quicksilver have most likely already seen this demo before, but I'll link to it anyway as it has a good set of pictures and descriptions which I found useful and others might too.

http://www.angelo.edu/faculty/kboudrea/demos/copper_HNO3/Cu_...

[Edited on 1-7-2011 by Hennig Brand]

quicksilver - 1-7-2011 at 07:06

The reason (obviously my opinion) why caps have been so successful in crude testing such as the "bent nail", etc are that one has more to work with and the consistent design of the energetic in a physical embodiment. Some authors / writers (Abel) insist that silver fulminate has a substantial friction sensitivity as opposed to mercury fulminate which has more impact sensitivity making the silver a much more dodgy thing to bring beyond a gram level. I think it's just damn hard to work with. That friction sensitivity becomes very annoying due to free powder's inconsistent dent on the plate. If I was to try it again I would make a tiny pellet w/ dextrin some smooth flexible polymer for a mold
-=Having samples that one knows the date of mfg is a valuable thing IMO.=-

Keeping copper nitrate truly dry is a challenge. I've once made some & used a "home-made H2SO4 drying bowl" to get those crystals as cleanly divided as possible, yet the air within the small storage bottle was enough to provide deliquescense once more after a 24hr period.

Hennig Brand - 2-7-2011 at 07:20

It may be just luck, but in the last few years and around 30 or 40 samples of silver fulminate, I found the sensitivity to be fairly consistent. I suppose it is also possible for a little static electricity to catch me off guard in a careless moment and ruin my day. I have never had any problems with silver fulminate yet, but I have a great deal of respect for it, and am very careful. Just the way it works in bang snaps speaks volumes about its sensitivety.

I know the sample in the picture above was made 2 summers ago before the start of the school year, so I can say with certainty the sample is 2 years old plus or minus 2 months. I should have put the date on the bottle, that is true.

Making a pellet with silver fulminate sounds like a good alternative to pressing.

quicksilver - 2-7-2011 at 07:58

During a British military testing agenda at the turn of the 20th century the use of dextrin was employed to limit the friction potential; eventually in the formation of a pellet via a method of tablet forming within an existing disposable mold. The best source of info on this was USBoM circulars and what's left of the (public domain) British testing material. {note: most of that stuff is gone now & it's tough to find fresh any longer.}
I will look for some that I may have kept from old UseNet days. There WAS some testing on the initiation properties of SF as it appeared more promising than mercury but the shelf-life issues with both were a serious impediment in the tropics and American climate. If I find it I post it. I do have a lot of material on primaries.

KernelPicnic - 31-1-2013 at 18:11

Yesterday I made some silver fulminate with 3g silver nitrate dissolved in ~10ml water, 10ml ~80% nitric acid and 20ml 95% ethanol. I used a warm water bath to heat it until it started bubbling, about 60C. The temperature then began to climb rapidly, reaching about 85C before I could get some ice to cool it. The temp stabilized at about 65C and kept bubbling for 10 minutes or so. When the bubbling stopped, I added ~20ml of water, then gravity filtered and washed with 30ml of water. I don't know what the yield was, but I estimate it was 1-1.5g.

I attempted to dry the wet crystals on a ceramic plate in a desiccator bag for a few hours, then realized it was probably a terrible idea and tried to scoop the still soaking wet powder into a container of water. The entire yield then spontaneously detonated, obliterating the plate and sending shrapnel everywhere. Most of it missed me, but I was hit with a few pieces in the forehead and both hands. I most likely didn't wash it nearly enough, it still smelled strongly of alcohol and nitric acid when it was drying.

Davin - 1-2-2013 at 02:52

Quote: Originally posted by KernelPicnic

Yesterday I made some silver fulminate with 3g silver nitrate dissolved in ~10ml water, 10ml ~80% nitric acid and 20ml 95% ethanol. I used a warm water bath to heat it until it started bubbling, about 60C. The temperature then began to climb rapidly, reaching about 85C before I could get some ice to cool it. The temp stabilized at about 65C and kept bubbling for 10 minutes or so. When the bubbling stopped, I added ~20ml of water, then gravity filtered and washed with 30ml of water. I don't know what the yield was, but I estimate it was 1-1.5g.

I attempted to dry the wet crystals on a ceramic plate in a desiccator bag for a few hours, then realized it was probably a terrible idea and tried to scoop the still soaking wet powder into a container of water. The entire yield then spontaneously detonated, obliterating the plate and sending shrapnel everywhere. Most of it missed me, but I was hit with a few pieces in the forehead and both hands. I most likely didn't wash it nearly enough, it still smelled strongly of alcohol and nitric acid when it was drying.

OK. Silver fulminate has an insane friction sensitivity. Yet you have an image of a glass thermometer in a glass beaker with silver fulminate between the two. Silver fulminate can detonate even under water from these conditions. Absolutely no glass on glass contact is acceptable when working with silver fulminate.

Same with ceramic plate. A light touch with a plastic spatula on a ceramic plate is enough to set it off. Paper towels are far more appropriate. Desiccators are also unnecessary. Just let it sit on some paper overnight.

nagyepf - 6-9-2018 at 20:48

You might say that AgONC is extremely sensitive,and has no practical uses other than bang snaps.
But in old times it was actually used in blasting caps,silver azide too.

Aerostato - 24-11-2018 at 08:45

Hello everyone,
I'm new here, i study Chemistry and I'm from Italy.

In the last months, I've been looking for some chemicals to make photographic emulsion. Among these chemicals, I got some extra AgNO3 that I decided to use to make AgCNO; so I easily got some absolute Ethanol too.

The problem is that I don't have any HNO3: is it necessary?
I thought that i can add some AgNO3 in Water:

AgNO3 --> Ag+(aq) + NO3-(aq)

And then add another Strong Acid, as HCl, to form Acid pH in solution.

Then add Ethanol and so on.

Do you think it coul work?
And if you think so, Does the acid need to be a Concentrade Acid or can I use commercial HCl (the one that you can find in supermarket)?

hissingnoise - 24-11-2018 at 10:06

The synth. won't proceed without HNO₃ and SF is way too sensitive for use as a primary ─ even handling it is inadvisable?

Better candidates would be acetylides and azides...

Aerostato - 24-11-2018 at 14:45

Could I ask you why? What's the role of HNO3 in the reaction?

hissingnoise - 25-11-2018 at 04:42

The reaction to produce fulminic acid is dependent on the formation of nitro-nitroso intermediates and these only form by the action of HNO₃.