13 replies to this topic

[CCH Concepts]

i have read a few posts on this mixture on hear and there have been warnings about how impact sensitive it is. i thought it might be a good idea for me to post my mistake.

i was (emphisis on the was) working on an impact primer to ignite visco fuse. i was working on different ratios of pot chlorate to phosphous, to try and make the mixture burn on impact rather than explode.

i had about 3g of the mixture on a piece of paper ready to be disposed of (failed ratio's). i was standing about 5 meters away from the powder when it self ignited. it was unconfined and went with enough force to knock me back. i would say this when with as much if not more force than the equivelent weight of a well confined flash powder. i was left with phosphous burns on my face and arms (im ok), but had i been working with this mixture at the time i could have easliy lost a hand if not worse.

but why did this happen?

i have ready about anatomy trisulphide can decompse to produce sulphuric acid, but this mixture was only mixed 10 mins previously.

and why did a mixture thats only seems to explode on impact and burn with heat explode. i would have expected a self ignition to have resulted in a fire?

　

this post is ment as a warning and also to ask those more experienced than me (being most i would expect) why this happened and how to make the mixture stable.

[portfire]

First off, I'm glad your ok. Second, that death mix has NO use in pyro AT ALL!!! I VERY much dought that it can be made stable.....Well there is one way.........DON'T MAKE IT!!!!

[CCH Concepts]

First off, I'm glad your ok. Second, that death mix has NO use in pyro AT ALL!!! I VERY much dought that it can be made stable.....Well there is one way.........DON'T MAKE IT!!!!

after stupidly making it i would agree. i thought making it wet, mixing minimising friction and static and respecting the mixture would be enough to use it safely. was not expecting spontanious ignition. i expected that with ammonium tri-iodide, not this stuff. i was wrong. out of interest i would like to know if anyone knows the physics of what happened, assuming it wasnt a cause of contamination.

[BrightStar]

From Ellern Ch10 - SELF-IGNITING FUEL-OXIDIZER SYSTEMS,

'Self-ignition under the influence of moisture has another and more complex aspect, which often has plagued fireworks manufacturers in the past. In fireworks formulas with chlorate and sulfur, the oxidation of the sulfur in the presence of moisture can lead to acidification of the system. In the absence of neutralizes, chlorine dioxide (C102) or (at slightly elevated temperature) chlorine and oxygen gas are evolved. These, in turn, act as strong oxidizing agents. If the rate of the initial reaction, induced by gradual infiltration of moisture, is slow, nothing worse than decay of the composition will result, but it can readily be seen that the decay can become self-accelerating to the point of selfignition.

Under ordinary conditions, the alkali chlorates will ignite or explode spontaneously or nearly spontaneously only when in combination with the most reactive fuels, such as white or red phosphorus, powdered arsenic, or selenium. The chlorates of the alkaline earth metals and of other heavy metals are even more reactive and spontaneous ignition can occur quite readily with a number of fuels and in the presence of moisture.'

It's mentioned that with Armstrong's mix if the phosphorus is reasonably unoxidised, even the friction of adding the powders together can cause ignition. Presumably then, sunlight, the mechanical action of paper uncrumpling itself etc. etc. could have triggered your accident. Ellern's comment is only ever to use milligram quantities mixed wet for use as paper caps...

I've had good success making strike igniters by embedding several safety match heads in BP/NC laquer atop a length of chinese time fuse. Maybe a safer option to try

[CCH Concepts]

From Ellern Ch10 - SELF-IGNITING FUEL-OXIDIZER SYSTEMS,

'Self-ignition under the influence of moisture has another and more complex aspect, which often has plagued fireworks manufacturers in the past. In fireworks formulas with chlorate and sulfur, the oxidation of the sulfur in the presence of moisture can lead to acidification of the system. In the absence of neutralizes, chlorine dioxide (C102) or (at slightly elevated temperature) chlorine and oxygen gas are evolved. These, in turn, act as strong oxidizing agents. If the rate of the initial reaction, induced by gradual infiltration of moisture, is slow, nothing worse than decay of the composition will result, but it can readily be seen that the decay can become self-accelerating to the point of selfignition.

Under ordinary conditions, the alkali chlorates will ignite or explode spontaneously or nearly spontaneously only when in combination with the most reactive fuels, such as white or red phosphorus, powdered arsenic, or selenium. The chlorates of the alkaline earth metals and of other heavy metals are even more reactive and spontaneous ignition can occur quite readily with a number of fuels and in the presence of moisture.'

It's mentioned that with Armstrong's mix if the phosphorus is reasonably unoxidised, even the friction of adding the powders together can cause ignition. Presumably then, sunlight, the mechanical action of paper uncrumpling itself etc. etc. could have triggered your accident. Ellern's comment is only ever to use milligram quantities mixed wet for use as paper caps...

I've had good success making strike igniters by embedding several safety match heads in BP/NC laquer atop a length of chinese time fuse. Maybe a safer option to try

the intention behind this is for an impact to ignite the fuse. i need a mixture that will ignite from an impact and burn rather than explode. simply lighting the fuse

[MDH]

the intention behind this is for an impact to ignite the fuse. i need a mixture that will ignite from an impact and burn rather than explode. simply lighting the fuse

Strike anywhere matches are made of Phosphorous Sequisulfide and potassium chlorate.

You can also use a simple chlorate mixture with a low temperature ignition and just strike it against red phosphorous and glass.

[CCH Concepts]

Strike anywhere matches are made of Phosphorous Sequisulfide and potassium chlorate.

You can also use a simple chlorate mixture with a low temperature ignition and just strike it against red phosphorous and glass.

the purpous behind this question is a product i intend to develop. but as im sure is obvious my experience is far below that of other members of this site and the idea could very quickly be nicked lol. for this product i require a fuse to be trigger using the force of an impact. would the above mixture do achieve this?

[scjb]

Out of interest, do you have a ballpark figure for product liability insurance in place?

[MDH]

Given that you want to publicly sell this device (or, as it appears you do) I would not recommend any chlorate and sulfur compositions. All chlorate compositions are too unstable for distribution to the public.

Perhaps you could try perchlorate, sulfur and glass powder or sand. Throwing such a mixture at the ground with significant force would likely set it off.

Still, nonetheless, it would be troublesome to have this product transported. I am sure most companies would reject it.

[CCH Concepts]

Given that you want to publicly sell this device (or, as it appears you do) I would not recommend any chlorate and sulfur compositions. All chlorate compositions are too unstable for distribution to the public.

Perhaps you could try perchlorate, sulfur and glass powder or sand. Throwing such a mixture at the ground with significant force would likely set it off.

Still, nonetheless, it would be troublesome to have this product transported. I am sure most companies would reject it.

i definatly had no intension of doing the sulphur/chlorate mix, as fun as it is, pretty much everything i have read has warned about it producing sulphuric acid. how would the above miture react, would it burn or explode? as for transport that will be delt with with in the design, idea being there will be a saftey cap/pin that seperates any impact sensitive mixture from its suroundings until use.

[MDH]

My only thoughts are that you would have to find a perchlorate composition that is still high in sensitivity but nonetheless requires a lot of force to initiate. As I said before, perchlorate, sulfur and powdered glass does not exhibit the same sensitivity to acid that chlorate does (so you'd want to watch the purity of your perchlorate very carefully) so it is a candidate. Safety could be further improved with a neutralizer such as calcium carbonate.

Still, this idea proves challenging because usually any amount of perchlorate composition can completely deflagrate from shock. For instance if you took potassium perchlorate and sugar or sulfur, and hit it with a hammer, it would go off with quite a bang. You would have something that explodes instead of burns from being hit off of a surface. In this case, a slow black powder based composition which ignites a fuse primed with a very thin (think 0.1mm) of layer of sensitive primer on top might work.

Given that you have said there is a safety cap, I am again thinking of the phosphorous sequisulfide composition which ignites easily from significant impact. Strike anywhere matches are, of course, widely marketed and distributed, so perhaps this could be as well.

I have to roll so I'll say more on this later.

[CCH Concepts]

My only thoughts are that you would have to find a perchlorate composition that is still high in sensitivity but nonetheless requires a lot of force to initiate. As I said before, perchlorate, sulfur and powdered glass does not exhibit the same sensitivity to acid that chlorate does (so you'd want to watch the purity of your perchlorate very carefully) so it is a candidate. Safety could be further improved with a neutralizer such as calcium carbonate.

Still, this idea proves challenging because usually any amount of perchlorate composition can completely deflagrate from shock. For instance if you took potassium perchlorate and sugar or sulfur, and hit it with a hammer, it would go off with quite a bang. You would have something that explodes instead of burns from being hit off of a surface. In this case, a slow black powder based composition which ignites a fuse primed with a very thin (think 0.1mm) of layer of sensitive primer on top might work.

Given that you have said there is a safety cap, I am again thinking of the phosphorous sequisulfide composition which ignites easily from significant impact. Strike anywhere matches are, of course, widely marketed and distributed, so perhaps this could be as well.

I have to roll so I'll say more on this later.

thanks for the advice. this is where this forum will greatly help, as when thing get more exotic i have no experience. it might be worth me emailing you and telling you exectly what im doing to help with the advice, only reason i dont say is because anyone can read this, just by searching on google.

[digger]

i definatly had no intension of doing the sulphur/chlorate mix, as fun as it is, pretty much everything i have read has warned about it producing sulphuric acid. how would the above miture react, would it burn or explode? as for transport that will be delt with with in the design, idea being there will be a saftey cap/pin that seperates any impact sensitive mixture from its suroundings until use.

By the way sulphur/chlorate mixtures are illegal in the UK under all circumstances, no exceptions.

There are other ways to skin the cat without having to add all the components into 1 composition. Which would make a device that would be transportable. Think about it.

Edited by digger, 24 July 2009 - 09:34 PM.

[CCH Concepts]

By the way sulphur/chlorate mixtures are illegal in the UK under all circumstances, no exceptions.

There are other ways to skin the cat without having to add all the components into 1 composition. Which would make a device that would be transportable. Think about it.

are you thinking maybe to things that come to gether on the impact that would cause ignition. if so, what chemicals are safe to use, dont invole liquids and would give a realiable ignition from contact every time. if you have any ideas, this could be a much metter solution.