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s_b_nilsen
May 3rd, 2006, 01:29 PM
Hi. I have read a lot about this yellow powder, on this forum and other places.
I have tried it some times at home, and the results are extreme :D

As KNO3 we use Krista-K fertilizer bought at Felleskjøpet (norway), calciumcarbonate is from a pottery, and sulfur from a drug store.

I have a mini-kitchen which I use in my garage when testing this powder, and we use to put a _little_ teaspoon in a metal box, put the heat on and see the reaction from the outside of the garage. This is extremely powerful if it melts good; one day we took almost a whole teaspoon in the container, used a low heat (so that _all_ the powder melts) and waited outside (maybe 5-6 metres away). It exploded heavily, and everyone got pain in the ears, and the guy who was standing closest got pain in the stomach :P

But it is not very smart to make big portions of this, so we have tried to melt it without exploding it, so that we can light it with a match afterwards. It works a little, but the reaction isnot even close to when it explodes while melting. It seems more like a extremely fast deflagration with a "whoff", and not the intense "bang" when heated.

Is it even possible to melt this and light it afterwards and get the same reaction?
It is also very risky, I can find a heatvalue that works nice many times, but suddenly one portion explodes..

Does someone have some experience they want to share?

Alexires
May 4th, 2006, 08:51 AM
Uhhh, I'm not to sure what to make of that.

First of all, read the rules about posting a new thread as your FIRST post.

....What is the Calcium Carbonate there to do?

*shrug* the reason it "explodes" when its near melting and you light it is probably because its so close to reacting it only takes a little energy to do so, and hence it propagates alot faster than when its cool.

That didn't make alot of sense, but you should get the idea.

Read around a little more yeah?

s_b_nilsen
May 4th, 2006, 04:17 PM
I ment potassium carbonate, not calcium carbonate, sorry about that.

Maybe I didn' explain this right.. This is the case:
When heated on an oven and melted, and you wait for the temperature to rise enough, it will explode heavily. This is cool, but a little dangerous and not very practical.

Therefore, we are trying to lower the temperature a little, so that it melts, but not explodes. When it is melted, we take away the heat-source and granulates the product. When this is ignited with a flame, it just burns really fast, so fast that you wont be able to think before the reaction is over. But it still not produces the same "detonation" as it does when it is heated to explotion. Do you see the problem?

I think I have read everything there is to read about this, on this forum, other forums, a couple of internet-pages etc, but I still have not solved this.

Sorry if I misunderstood the rules about first post... I thought that when I posted my first post, it would be sent to an Admin, and it would appear in the forum when the admin had approved my post..

nbk2000
May 4th, 2006, 06:02 PM
As a general rule, new members shouldn't make their first post as a new thread, since they tend to get banned for stupid mistakes.

However, somtimes a newbie does post something interesting as a first post/new topic, in which case it gets approved.

But they still risk stepping on the mine in the grass, so it's not something we encourage.

Anyways, what ratios of KNO3/KCO3/S are you using? By weight, not volume, please.

Having read about this in the past in one of the PMJB books, the idea occured of filling pipe bombs with the powder, and scattering them around a place that you'd be setting on fire.

As the heat of the fire reaches the pipe-bombs, the powder melts and explodes, making it too dangerous for fire-fighters to approach, ensuring total destruction of the target.

No dangerous or complicated explosives need to be made beforehand, as the yellow powder is inert prior to melting, and extremely simple to make. :)

I don't think this powder can detonate at less then melt temperatures, as it's not reactive enough at room temperature.

And, if I remember correctly, it was intended as a replacement for black powder, so it's not supposed to detonate anyways. That was an undesired risk of the manufacturing process.

You could try shocking it with a detonator, and see if that worked. Or, get it hot enough to melt, then hit it with the detonator while it's in a molten state. Presumably it melts at a temperature well below it's auto-ignition temp?

Have you tried casting it? It may detonate as a solid mass, but not as a granular powder, because shockwaves don't transmit through powders as fast as a flame front can.

s_b_nilsen
May 5th, 2006, 03:15 AM
I'm using 54.54% KNO3, 27.27% potassium carbonate and 18.19% sulfur.
I have tried to fill pipe-bombs with it, and that works great. But it's not possible to make use of it's full potensial, since some of the powder will melt and explode, while most of it still not have melted, and then just burn.

Seems like it's impossible to get a practical product out of this...
But it's sure been fun playing with it. :p

(smilies here use lower-case letters, not UPPER-CASE like you've been using. And avoid multiple-postings...liable to get you banned. NBK)

Kleng
May 5th, 2006, 10:55 AM
Is it possible to use Sodium Bicarbonate? (baking soda)

I got a bag of Krista-K in my garage, I'm from Norway too. In addition an half kilo of sulfur and baking soda. This explosive looks really interesting.

corrosive
May 6th, 2006, 05:01 AM
Although this explosive sounds good, it has it's downsides. Including like a post earlier said, it has a tendency to transfer heat horrible. Quick scenario, (as nbk posted earlier), burning building and there are pipe bombs scattered abroad, say 1.5"-2" diameter and, 5"-8" lengths. When the pipe heats up the walls are really hot so only the powder touching the walls will be able to transfer the temperature enough to give melt to the substance and cause explosion. So technically you get half or even quarter of the possibility when it blows.

If this is actually what happens inside a pipe with this compound, you can maybe step it down a bit with little or no decrease in power, instead of using 1.5"-2" diameter pipes... use 0.5" to 1.0" max, so you give the powder enough time so even the very core melts, therefore you get full detonation and get your full result. What would be very fun to mess around with a couple times. Get some .5" pipe with the length of about 2 feet or even longer if you wish, throw that in a fire capable of heating up both ends equally and watch it go.

Sounds like a very intresting "shaped" charge if you will. Although this compound has it's uses, only under the extremist of conditions will you need to use this. As there are better compounds available to put in its place. Because of its sheer simplicity, it would be real pity to put this compound to rest in the endless archives of this forum, without a budge to mess with it. Maybe we can work something out during its heated liquid properties to enhance the effects when it dries.

Question, what actually happens to the substance when you sucessfully melt it. Because as it is in powder form, its not as dense as it would be say..in liquid form. When you sucessfully melt it, and it dries you've actually made it more dense. You noted that it goes "Whoof" that sounds like unconfined whistle mix being KClO4:Sodium Benzoate (70/30) or, a simple flash composition to me. Does it burn instantaniously or is it like modern gunpowder, it catches flame for a few seconds and its done, more of a "pushing" manner.

BTW it would actually be a good idea to find out what temperature this mixture actually starts reaching melting point, then slowly up it little by little to see when it detonates (doing this a few times). Judging by the 3 chemical melting points (Wikipedia), KNO3 334°C, KCO3 891°C, and S 115°C. The sulfur melts down first acting as a "reactor" and setting off the compound, my personal guess would be around the temperatures of sulfur's melting point, plus:minus 20°C. When this information will be secured we wont have to fret while managing or casting this substance.

s_b_nilsen
May 7th, 2006, 04:28 PM
Is it possible to use Sodium Bicarbonate? (baking soda)

I got a bag of Krista-K in my garage, I'm from Norway too. In addition an half kilo of sulfur and baking soda. This explosive looks really interesting.

Where in Norway do you live?
I have read on this forum that you can use baking soda, but I have not tried it myself.
Anyways, I think it's cheaper and better to buy potassium carbonate. Here (http://www.hana-holmens.no/) you can buy 5 kg potassium carbonate, it costs only 90 NOK. (about $15)

Corossive: It is very difficult to find the excact melting point.
I can do many successful meltings without explosion, but then it can suddenly explode. It seems that it is very unreliable...

corrosive
May 7th, 2006, 05:51 PM
Well, theres always a way to check substance temperatures like this, a simple infrared thermometer. Now, I'm not making you buy one, but their about as handy as a wrench is to a plumber. Prices range from $40-$500 maybe more. Here's a simple one I found just to give you an example. Im gonna have to get me one of these soon, they measure temperature without touching the substance, -33° to 220°C. Its simple but it gets the job done down to ± 2°C.

http://www.professionalequipment.com/xq/ASP/ProductID.2433/id.22/subID.177/qx/default.htm

Also, I'm still a bit questionable about what happens when you successfully melt the compound down, put a fuse in it, and let it dry. What are the effects upon ignition, could you please describe them a little better? :)

s_b_nilsen
May 8th, 2006, 02:48 AM
When it's successfully melted, dried, granulated and lighted with a fuse, it just "whop"'s away. I can't see any flame, it just makes an extremely fast "whop" and it's gone.

nbk2000
May 8th, 2006, 02:59 AM
Like Black Powder, not Smokeless (which just fizzles)?

And how fine the granulation?

s_b_nilsen
May 8th, 2006, 03:06 AM
Yes, something like black powder, just the reaction happens a lot faster.
But it is strange that the reaction which appears when it's lighted is so different from when it's heated (the reaction when heated is much like a detonation)

corrosive
May 8th, 2006, 03:43 AM
Wow sounds pretty powerful to me, sometimes you can measure relative power by getting like a foot length cardboard tube with like a 1 to 2 inch diameter. Now you can find one of these real quick, aluminum foil...when its used up your left with a cardboard role..its not strong but we will get to that later, get about a gram or two sized amount and put that in the middle of the tube. Light it either with a fuse through a poked hole..whatever.

Now the results can be either, it smokes out the sides or its so fast that it doesnt have time to get out the sides so it just rips through the cardboard. If these tests are successful you can add a layer of tape, more cardboard, dry or glued if you have the time, to see how strong it really is. But if its not successful, try to actually fill a ping pong ball with one of these then stick the ball into the cardboard approximately in the middle. If these tests are successful, that is what I call "relatively powerful" meaning its good to use in salutes, stars and such, mostly salutes because you always plug both ends of each salute and you never want them to pop out, losing brisance.

It detonates when you heat it up because its reaching unstable temperatures of the oxidizer and catalyst, I guess it just cannot handle the temperature and the energy holding the molecules is broken, and released with enormous energy.

Also,I have no idea why you need the potassium carbonate in this mixture, Someone asked this earlier and I cant find a reply.

One more thing, have you tried using the melted down granulated mix into a heavy cardboard salute, if you do have the time you can quickly construct one and tell us how that goes, describe the brisance and shattering power, that'd be awesome thanks.

s_b_nilsen
May 8th, 2006, 04:07 AM
I think the power is very, very good.
We filled a tube from a firework-battery (3-4 mm carton, 1-1.5 cm diameter) with a few grams of yellow powder. We did not plug the holes, but when we lighted it, it made a "bang" and blew the carton to pieces..

corrosive
May 8th, 2006, 04:11 AM
Intresting results, this actually sounds like a very nice salute mixture, congratulations you have a "relatively powerful" mixture :) .

I wonder if you can modify it in anyway, in terms of adding more things to gain say, power.

s_b_nilsen
May 8th, 2006, 05:17 AM
It is indeed a powerful mixture, but compared to the results when heated, it is a bit disappointing...

corrosive
May 8th, 2006, 06:27 AM
I've just discovered there are more threads concerning this "fulminating powder" it is pretty common and it is said you can melt the carbonate and sulfur together, dry it and granulate it, then just powder in the KNO3. It truly detonate's when heated on a small spoon, this is very interesting. Also when granulated very fine it gives amazing brisance with miniscule amounts. I think this a good salute mixture if you have the time and energy to prepare it.

One downside I noticed and read. The Potassium Carbonate is very hygroscopic so before preparation its best to dry it out then you can melt it down, and this also means you cannot store the finished mix simply as it is more hygroscopic then NH4NO3.

Other then writing all this down on paper and saving it in my folder of upcoming projects, I will have to try this myself in the near future.

s_b_nilsen
May 8th, 2006, 06:43 AM
I am aware of the threads in this forum.
I have tried to melt the sulfur/carbonate together, but it can explode even without KNO3 (not that powerful, but it can explode)

Kleng
May 9th, 2006, 10:55 AM
What if you don't melt it? Only grind it very much inn a ball mill? Would this be danger or could it be done without risks? If not, grinding sulfur and KNO3 together and then add grinded Potassium Carbonate?

ShadowMyGeekSpace
May 9th, 2006, 09:58 PM
Given the ignition problems in powdered form, what if you melted it, cast it with a hollow core, and used a fast, hot burning substance such as fine mesh MG + Ammonium nitrate in the core? Maybe thermite?

s_b_nilsen
May 10th, 2006, 03:42 AM
Kleng: That would not work. The point by melting this, is that the sulfur and potassiumcarbonate will react, and make polysulfides.

ShadowMyGeekSpace: Yes, I have been thinking about this, or maybe use some kind of detonator to ignite this...

ShadowMyGeekSpace
May 10th, 2006, 05:45 AM
You wouldn't want to detonate anything, a deflagration would be more suited to heating the whole substance at once I would think - keeping it within its confined atmosphere during heating. A detonation could be too fast of a reaction destroying that confinement, and thus reducing enviornmental pressure on the yellow powder when it starts to detonate, as well as moving the yellow powder away from the heat source at a higher velocity.

By giving it a core and heating from there with flash or something , you might beable to achive heating all of the yellow powder while keeping it contained for maximum effectiveness.

I could see a detonation working in the situation where the core was composed of yellow powder and was surrounded by something else, like a shaped charge encompassing the whole of the yellow powder. Even something simple BP would probably do the trick.

s_b_nilsen
May 10th, 2006, 06:29 AM
Maybe you've right..
Anyways, with a heating core of thermite/flash, some of the simplicity of this compound disapperars.. I don't think I will find a practical use of this.

Alexires
May 11th, 2006, 10:12 AM
If your having ignition problems, try KNO3 + Sugar. That burns fairly hot in a 50/50 (weight) ratio.

If you dissolve the sugar and KNO3 in water and then evaporate the water leaving you with a fast burning, hot powder.

ShadowMyGeekSpace
May 11th, 2006, 08:13 PM
Not as hot as MG + an oxidizer.... just go to walmart and buy one of the little "fire starter" blocks from the camping/sporting goods section, its a block of magnesium with some flint shoved on it...... it's what I use for MG :)

++++++

What's wrong with the above post?

Correct or be banned.

NBK


++++++

Post corrected, sorry.

ShadowMyGeekSpace

Cube1
May 11th, 2006, 10:57 PM
you have to melt it without ingnit it so you cant melt it with bp
there has to be a reaktion betwen the S and the K2CO3
2 K2CO3 + 2 S ---> 2 K2S + 2 CO2 + O2
this can fourther reakt with the kno3
2 K2CO3 + 2 S ---> 2 K2S + 2 CO2 + O2
then it is two times faster as every flash composition
here is a vid of
14g yellow powder (http://home.arcor.de/kinger2/vids/14g%20Yellow%20powder/).

++++

Since you contributed something to the discussion, you weren't immediately banned for extremely poor grammer.

Improve rapidly or continue contributing every post, otherwise you'll be banned for it.

NBK

s_b_nilsen
May 12th, 2006, 09:36 AM
The problem is not to ignite it..
The problem is that if it is ignited by a flame, it only delfagrates, but when heated and melted, it detonates ;)

Kleng
May 13th, 2006, 01:39 PM
What about if you put some yellow powder on a standar pan, thereafter you put a KNO3/sugar "smokebomb" under the pan and ignite it with a long fuse? It would melt because of the heat and probably detonate.

FUTI
May 15th, 2006, 08:17 AM
Polysulfides are bitchy substance to play with, but considering the fact people here play with peroxides I don't think that will stop them.

Mixing two salts with one common ion can make mixture that have melting point different from the salts it is made of usually lower (which is good in my opinion). I would try to use K2CO3 (not KCO3 as someone wrote above arghhh!) and Na2CO3 (baking soda can be used but must be calcinated before) and find their mixure that melts at lowest temperature and fuse it, cool it, grind it and mix in sulfur and fuse it again. That should give good mixture to be pulverised and mixed with KNO3.

Maybe a linen thread soaked with KNO3 and sugar and coated with a piece of plastics can make good melting/igniting device if you place it in center of tube filled with "yellow powder".

nbk2000
May 21st, 2006, 08:34 PM
Another use for yellow powder comes to mind - anti-torch barrier material for safes.

Small amounts of the mixed, but unfused, powder are encapsulated in metal tubing, and embedded in the concrete safe wall material.

When someone tries to cut it with a torch or lance...BOOM!

Mangled thief, damaged or destroyed torch/lance, and a definite alarm. :p

nathan
June 7th, 2006, 07:56 PM
I tested the yellow powder using sodium bicarbonate instead of potassium carbonate. My results were disappointing.

I mixed the correct amounts (substituting NaHCO3 for K2CO3 of course) and then ball milled them for 5 hours. I tried to ignite the ball milled mixture, but all I got was a bit of smoldering.

When I put 1 tsp in a tin can and let it sit on a burner all the reaction I got was a popping sound and the spewing of burning sulfur in the air. I tried a tablespoon of the mixture in the can and got similar results, except the noise was slightly louder and more mixture was spewed into the air.

I tried fusing the mixture and then granulating it but the best result I got was a BP-like burn rate.

KMnO4
July 10th, 2006, 09:24 AM
At http://www.experimente.org/Knallpulver.htm you can see a video of 14g of yellow powder being heated on a metal plate over a bunsen burner untill it goes off.

BlackSky
July 12th, 2006, 08:15 PM
Nathan .... I think when they said that Sodium Bicarbonate can be used ... they meant to convert the bicarbonate into Carbonate by dissolving it in water and then boiling it of about 100*C for a 10 minutes. Then , let it dry. It will become Sodium Carbonate . Then you can use the resulted Sodium Carbonate instaed of using Potassium Carbonate.

By the way , I didn't tried to make Yellow powder before but I've read alot about it.

c.Tech
July 15th, 2006, 01:02 AM
BlackSky - to convert bicarbonates to carbonates you don’t have to dissolve them in water, just heat as hot as you can get it.

I would just buy it from the supermarket as washing soda.

BlackSky
August 5th, 2006, 09:05 AM
Thanks c.Tech for the info.

By the way , Does anyone tried to detonate Yellow Powder the same way of detonating ANFO ?

Maybe it can be detonated the same way . Thus , It will be easier in preparing than ANFO and also more powerful .

pearlcrash911
August 12th, 2006, 12:00 PM
What about using sterno?

You could cut cardboard to make supports on both sides to elevate a pipe bomb, and then place a fused can of sterno underneath.

Not only would it react as it would in a fire, but you would also have a bit of a delay.

waauu
September 14th, 2006, 01:30 PM
Can you melt the carbonate with the sulfur, before mixing it with the nitrate? It sounds a little bit dangerous to melt them together. Has anybody tried it?
I will try that maby tonight, and I will use sodium nitrate and sodium bicarbonate (NaHCO3).


{Watch your grammar. This is your first, last, and only warning - megalomania}

Sausagemit
October 25th, 2006, 03:43 AM
I just tested about 7 grams of "yellow powder" with the bottom of a pop can and a propane torch. The suspense was killing me because I wanted to see what the hell it was doing!! It was worth the wait though. I saw the mangled remains of the pop can flying every which way and a fairly loud report.

What I'm thinking about trying is a taking a pipe that transmits heat well (copper is the most likely culprit) and then making a CaSO4 AL cast incideary around the pipe. It might be more trouble than what it's worth and it may not even go off.

The thing that is bothering me is will this stuff melt quicker when packed or loose?

sparkchaser
November 10th, 2006, 02:58 PM
So I was thinkin'. Some of the model rocketeers out there using the KClO3/sugar fuel that is so well known are, instead of melting it for a casting, disolving the above completely in water, drying it in the oven at low temp., and using as is (it's very plastic while warm, and can be formed).

Since a solid transfers shock easier than powder, use an AP detonator on the resulting block or sheet. Failing that, it could easily be granulated from its solid state.

Cindor
November 10th, 2006, 10:26 PM
The rocket mixture "so well known" is KNO3/Sugar, no KClO3... don't try to melt KClO3/Sugar mixture.

c.Tech
November 10th, 2006, 10:58 PM
I've heard there are pyro's out there that have has success with NaClO3/sugar rockets.

sparkchaser
November 11th, 2006, 11:20 AM
Whoops! friends don't let friends drink and post!:o

Anyways, KClO3 is soluble in water (7.3g/100ml).
Calcium Carbonate...... poorly soluble/ breaks down to become calcium hydroxide + CO2.
Sulfur...... poorly soluble.

I'm guessing that it won't work, but that's just a hunch.:rolleyes:

Universal
November 11th, 2006, 08:35 PM
What about if you put some yellow powder on a standar pan, thereafter you put a KNO3/sugar "smokebomb" under the pan and ignite it with a long fuse? It would melt because of the heat and probably detonate.

This wouldn't be ideal, the thing is it would heat up too fast causing it to catch alight before it melted, this results in the powder "merely" burning (slowly too) and making lots of SO2. The best way to do it is an electric element on a relatively low heat, that is if you're willing to do that sort of thing to your element:D .

Anyway, I made some yellow powder earlier with homemade Na2CO3 and it worked well. I found that although it makes a bigger report in larger quantities, it is much more efficient to do it in lower amounts, and also it is a much cleaner, sharper report in lower amount. I did 10g and it went: ffft-BANG-shhh. And Then I tried 2g, and it went: BANG, but wasn't as loud.

By the way, does anyone know the products of yellow powder. I am guessing that it is KNO3 + K2CO3 + S --> KNO2 + CO2 + K2S.
I'm sure there are many answers as it is with black powder.

Cindor
November 11th, 2006, 10:11 PM
10 grams makes more BANG than 2 grams... make a comparasion with flash powder and heard what happens... 10 grams are much more louder than 5 times 2 grams BANG.

Universal
November 12th, 2006, 12:01 AM
Sorry about saying the stuff about 10g being worse. I made up a new 'proper' batch with much more precise measurements and purer K2CO3 and the report was deafening, it blew up the steel container it was in with ease. I also tried 2 grams and it was pretty much the same as the older stuff I made but it went off faster.

DONMAN
December 10th, 2006, 03:14 AM
I made some of that today. I first melted the S and the Na2CO3 together then added the KNO3. I notice that the mixture of the S and the Na2CO3 gives off a weird natural gass smell even after it's cooled. What is this smell? Is it some weird H2S? The powder works... but what is that stink. Anyone elese had similar experiances?

Universal
December 10th, 2006, 05:03 AM
It isn't 'H2S' because there isn't H2 in the reaction. Maybe it is CS2 or small amounts of SO2. But you never know, sulfur on it's own has little to no smell, t is actually H2S in small quantities. The stuff used in natural gas to make it smell is a thiol, which all smell bad, called methanethiol or mercaptan CH4S.

Making yellow powder I have never had this problem, remember just because there is no KNO3 when the Na2CO3 and S are mixed doesn't mean they won't react, don't get it too hot.

Cindor
December 10th, 2006, 05:10 AM
Is Na2CO3 not NA2CO3, and is H2S not SH2.

DONMAN
December 10th, 2006, 05:05 PM
My bad, I need to stop posting so late at night. :) I didn't clean my grinder throughly and the mix could have contained maybe 1-2 percent carbon, when I went to heat it on my hot plate on low. I was doing this out side under a shed in the rain.... so I thought that maybe some moisture could have been sucked from the air causing some sort of H2 to interfere. That is why I suggested that it could have been H2S.....


This wikipedia article backs me up "H2S arises from virtually anywhere where elemental sulfur comes into contact with organic material, especially at high temperatures." I might of had some charcoal in the mix, this could have been the cause for the H2S. Wikipedia also says that it corrodes copper pennies... So I am going to test it by taping a copper penny to the lid of the jar and seal it over night.

When you just burn the mix does anyone get molten sulfer left over? If not, do I need to add more Na2CO3? So that the Na can form Na2S?

Universal
December 11th, 2006, 01:02 AM
Try getting the gas in a jar with only some CuSO4 in it, shake it, if it is H2S then there will be a blackish precipitate of CuS.

Also Na2CO3 reacts with S like so:

2K2CO3 + 8 S --> K2S3 + K2S4 + 2CO2 + SO2

So it looks like SO2 is the culprit however hydrolysis of K2S3 will make H2S so it is a combined force.

DONMAN
December 16th, 2006, 01:07 AM
My penny corroded.... that means there was defiantly some H2S. It was almost black after 5 days.

nbk2000
December 16th, 2006, 11:13 PM
Sulfur always produces some H2S in contact with air.

Universal
December 16th, 2006, 11:52 PM
That is the reason for it's smell. Also doesn't copper react directly with Sulfur, I know silver does.

Also a question, would yellow powder with NaOH substituted for the Na2CO3, as NaOH heated with S forms polysulfides, wouldn't it work well, I know it would be hygroscopic but I wouldn't plan to keep any over time.

c.Tech
December 17th, 2006, 02:56 AM
Also a question, would yellow powder with NaOH substituted for the Na2CO3, as NaOH heated with S forms polysulfides,

IIRC NaOH reacts with sulfur to from a sulfide, I could be wrong though.

chemist646
May 24th, 2007, 08:48 AM
Yeah, I done this before with sodium hydrogen carbonate, suphur and potassium nitrate.

Burns pretty fast, but nothing spectacular really. It does make quite a bang if you heat though, on a spoon or something. The potassium nitrate and suphur however, were not melted together so maybe this has an effect on the burn rate.

SEQUENCER
June 15th, 2007, 10:30 PM
Sounds like a good way to destroy a car engine, if one had some means of filling a container the size of shoe polish and attaching it to an engine block by means of a magnet. It probably wouldn't penetrate the block itself but could disable the vehicle by destroying less dense parts ie hoses, the battery, wires. Just a thought.

Zer4tul
July 5th, 2007, 03:37 AM
I recently tried this 'yellow powder' with sodium carbonate from the pool chemical isle.

As you all have found out it makes quite a bang when heated. A small pipe was filled with about 10 or so Grams and was placed on/in a padlock. I then put a pencil torch under the assembly and let it sit for a couple minutes. With quite a large explosion, it destroyed the metal loop on the padlock (sorry if it has a name) that locks it to whatever.

Might have the potential of a lockbuster that one could casually walk away from and comeback when ready. :rolleyes:

Rbick
July 5th, 2007, 01:46 PM
Well I guess that would work if you had limited options. But why not just place a 4g charge of PETN initiated by .2g AP in a paper tube or straw and completely obliterate the lock? I don't think it would even take 4g to do it. Wouldn't the metal tube add too much shrapnel for just trying to open a lock? And what happens to the pen torch?

It doesn't seem like a bad idea if you are limited on options, but there are many alternatives that are more safe and easier. Even KClO4/Al flash powder works in a paper tube against weaker locks. I opened one of those cheap safes easily with 4g of flash powder. It actually shot the locking mechanism through the back wall of the safe. Or you could fill the lock with liquid explosive and detonate that with a small amount of primary. Sorry I'm a little off topic, but I think it applies.

Secong Nature
October 29th, 2007, 06:26 PM
The way I see 'yellow powder' is either as an alternative to black powder for pyro's who cannot, for some reason get charcoal.

Another use would be for a booster for something like ANFO when the powder is melted and detonated.

Also would it be possible for me to use Li2CO3, as this is the only carbonate I can readily get.

Charles Owlen Picket
October 30th, 2007, 10:40 AM
I think the fascinating thing here is that there is the use of the term "detonate" on exposure to heat (see Davis). There is the element of self-containment explosive reaction that exists for the criteria for detonation; but we know that there is much more than self containment as regards that definition. IF memory serves, this is where some authors interchange the terms "explode" and "detonate" (& it makes me crazy).
How fast DOES it shoot? Most likely in the low 1200mps range (if that). This assumption was made by Shmizu in a paper on burst charges where he thought that higher levels of speed are unnecessary for shell burst, etc. {Highest level of speed for deflagerants; from a series of white papers published both privately & from Propellants & Pyrotechnics.}

Would yellow powder initiate a secondary? Personally, I doubt it; but it could initiate a select sensitive one [as BP had w/ NG...]
Is a carbonate pivotal in the reaction & if so why? This (IMO) is the interesting portion of this material.

PeterB2
October 30th, 2007, 12:07 PM
Li2CO3?!? You are able to obtain this OTC cheaply? That seems like it would be exhorbitantly expensive...why not just use washing soda (Na2CO3) found at any grocery store or pool store?

What is your source of Li2CO3?

nbk2000
October 30th, 2007, 12:23 PM
Probably a pool chemical, as I've seen it there before, though it's only like 6% of the active ingredients.

PeterB2
October 30th, 2007, 04:25 PM
Hmm...are you sure it wasn't lithium hypochlorite? I've seen that as an alternative (but expensive) shock agent called "lithium shock" (don't think its 100%). I can't imagine why using Li2CO3 would be an advantage though, assumedly for acting as a pH up agent...

Secong Nature
October 31st, 2007, 02:30 AM
I can get the lithium carbonate from a pottery store (some glaze I suppose), it's called just lithium carbonate so I'm assuming high purity stuff.

Though I'm assuming a high price due to it's rarity and probably sparing use in ceramics.

s_b_nilsen
October 31st, 2007, 05:03 AM
Another use would be for a booster for something like ANFO when the powder is melted and detonated.
This would probably not work in the real world.
To set off this explosive you have to melt it, and it is "detonated" when it reaches a certain temperature. But the powder closest to the heatings source will melt faster, and then just some of the powder "detonates", and then lights the rest of the powder, which deflagrates. So it is very hard/impossible to set off larger quantities of yellow powder.

And as Charles Owlen Picket; How fast does it shoot?

Charles Owlen Picket
October 31st, 2007, 10:31 AM
And as Charles Owlen Picket; How fast does it shoot?

To the best of my understanding it does not exceed contained deflagerant compositions (max 900-1200mps) which would raise doubt about the concept of detonation [albeit this occurs through self-containment with "yellow powder"].

Barnacles
November 10th, 2007, 10:26 PM
This is just a brainfart not sure if it has been mentioned but, anyone think of making a pipe bomb with a heating coil that is coiled inside the pipe it should make contact with much greater portions of the powder, with external heating you may just get all of it. Maybe use a coil that gets red hot or even 100 ft of nichrome wire or something just putting some thoughts forward.

EDIT this could have the added benifit of spraying red hot metal all over...

nbk2000
November 10th, 2007, 11:24 PM
This would be ideal for preventing fire suppression efforts in an arson attack, as you can get the ingredients with no problem, mix and transport the filled pipe-bombs with zero risk, and leave them scattered about in the target to get heated in the arson fire, and prevent fire fighters from getting near it. :)

Thermiteisfun
November 11th, 2007, 01:47 AM
Oh my... If you have a length of nichrome wire coiled in a pipe with this mix, all you would need is an analog watch for a timer and a suitable power supply!
Run the nichrome up the minute hand, the pos (or neg) terminal to the hour for a 1 hour 5 min timer.

You could use a regular house current if you take the wire from a toaster! Good idea shadow!

Edit: Brain storm idea... to make the heater element you could coil the nichrome around a paper tube half the diameter of the planned container for equal heating.

Barnacles
November 11th, 2007, 11:34 PM
Just curious does anyone off hand know the temperature of a hot exhaust pipe from a car, and the rough detonation temperature is of this product( I should clarify, I mean as what temperature is needed to make this powder detonate or make it capable of detonation)? Sorry to go off topic again , but I had another brain fart, as a product like this actually seems useless at first but upon further brainstorming seems to have endless practical or impractical (which isnt always impractical lol)applications.

Anyway I was thinking of several Ideas, involving this, for sabotage, this stuff could be put in a tail pipe, around the brakes of a car, or in the brake drum, or any part of a car that gets hot. I also wonder if it could be detonated via stuffing the tip of a christmas light with it and attaching it to a power source, and this could make for a safe detonator, that has no chance of detonating while it is in transport(at least by accident).

I could even see ovens or toasters being rigged, either for specific targeting or even random terrorism via tampering of store bought products. The uses of this are endless, all you have to find are ways of heating this remotely or getting your target(s) to heat it for you.

Sorry if this is off topic. I will try to stay more on topic in the future as I really appreciate these forums and wish to stay around.

Charles Owlen Picket
November 12th, 2007, 04:25 AM
A great deal depends on the type of motor, the exhaust manifold, and the design. Easily 300 C, you could depend on that; I'm pretty sure.

megalomania
November 13th, 2007, 06:29 AM
Don't quote me on this figure, but I seem to remember reading about exhaust temperatures required to get the catalytic converter to work resulting in the tailpipe reaching about 400 degrees. Again, I may be way off, and I can't even say if that is C or F degrees.

ex1ge
November 13th, 2007, 12:38 PM
Catalytic converters start working at around 450 degrees celsius, with temperatures rising to upwards of 900 degrees.

Yafmot
January 20th, 2008, 02:01 AM
I spent six years designing cats at an aerospace metals development company down in LA. Ya' Wanna' warm up a cat? Just loosen a sparkplug wire. A cat acts like an afterburner, cooking Hydrocarbons and CO into CO2 & water. Send in a jug's worth of unburned fuel, along with the extra Oxygen from the "smog Pump" (actually just an air pump), and that sucker will get hot enough to shift the Alpha Alumina washcoat to a Gamma phase (which glazes it over), and fuse the Cordierite substrate into a solid blob.
This happens at around 1500F. (Hot enough for you?)

Naturally, this is going to be more noticable with a four banger, less so with a six, and with a V-8, they probably won't figure it out until it's too late.

I jumped from the second page to the 8th, so maybe it's already been discussed, but why not think about a pyrotechnic heat source? I'm thinking maybe something on the order of a downscaled tube & shell heat exchanger, sort of like those locomotive boilers where the hot gases from the firebox are routed through parrallel tubes in the water.

If you could get the burn rate and caloric content right, it would heat the comp pretty much isothermally. Maybe one set of tubes could bring it up to the liquid state, and a second set would put it over the top. Just a thought.

gliper
April 12th, 2008, 06:35 AM
Has any one tried sodium PERcarbonate-carbonate mix like SUN oxy cleaner? It seems like I could just use less nitrate because of the extra O.

Any idea on the ratio of sodium PERcarbonate to carbonate in said cleaner?

frontier27
April 18th, 2008, 03:45 AM
This is my first post, I will try to give some insight on yellow powder. I have been an avid poster on rec.pyrotechnics for years. However, first I want to make sure you all are not referring to a powder that was patented to be a replacement in black powder muzzle loaders. I might have misread a previous post, but I was not aware Dr. Shimizu, who invented H3 even used yellow powder as a burst in shells. If true, thats very interesting. In its unheated deflagrating form it sounds as if its a black powder substitute. I just want to make sure that I am not getting this confused with golden powder.