Potassium Chlorate and Sulphur

[Timm]

I once had a chlorate star/H3 shell explode in the mortar tube.. completely obliterated it. Half-convinced it underwent a partial detonation from shock of setback.. might have been dabbling in the benzolift around then though too, heheh. Trying to remember if i put the H3 on hulls or used the coarse, screen-corned powder.. Is foregoing the rice hulls (or what-have-you) asking for trouble in that type of arrangement? (no. 5 can, around 2" dia.) Anyway, put me off of the H3 for a while, but now i'm back because i hate when only some of my stars light!

 

Would the shell have blown up had i used BP instead of the H3? I dont think so. But on the same hand, what about all those hard, little, mostly KclO3 pellets getting smashed together for a second with black powder all over them and everywhere in between?

 

I guess all i can do is just not be suprised either way, until i figure out which setup works the best / blows up the least often. Chlorate shell totally confetti-ing a mortar tube is ah.. just one a those things that happens sometimes i guess

[cogbarry]

There is a chance that the sulfur reacts with components in the air to make sulfuric acid.This I read from some safety tip site.The chance is minimal but you still wanna be careful.Use pure sulfur and no agri grade.My main question is why even use chlorate and sulfur?

 

I'm not mixing them intimately. I want to try some star formulas that contain sulfur and was wondering how to mitigate potential issues with it coming in contact with sulfur in the burst and/or prime. From the responses so far, it seems that the prime layer itself will help mitigate potential friction between the chlorate stars and burst, using pure sulfur will help mitigate risk of chemical sensitivity/self ignition. Again, I've been building a couple years and have avoided using chlorates as I had been given this advice by more than one person. Now I'd like to try some different star comps and thought I'd seek advice on chlorate stars and safety. I really hate the idea of a shell igniting in my hands while building .

[cogbarry]

Another chlorate question:

 

I believe someone mentioned the fact (at least I think this IS a fact) that chlorates were no longer used in commercial shells. Was this for environmental reasons, safety or both?

[cogbarry]

I once had a chlorate star/H3 shell explode in the mortar tube.. completely obliterated it. Half-convinced it underwent a partial detonation from shock of setback.. might have been dabbling in the benzolift around then though too, heheh. Trying to remember if i put the H3 on hulls or used the coarse, screen-corned powder.. Is foregoing the rice hulls (or what-have-you) asking for trouble in that type of arrangement? (no. 5 can, around 2" dia.) Anyway, put me off of the H3 for a while, but now i'm back because i hate when only some of my stars light!

 

Would the shell have blown up had i used BP instead of the H3? I dont think so. But on the same hand, what about all those hard, little, mostly KclO3 pellets getting smashed together for a second with black powder all over them and everywhere in between?

 

I guess all i can do is just not be suprised either way, until i figure out which setup works the best / blows up the least often. Chlorate shell totally confetti-ing a mortar tube is ah.. just one a those things that happens sometimes i guess

 

I've been shooting for two years now (well, maybe 3 if you count my early backyard stuff) and I've seen 3 shells blow up in the gun. One was a color shell and we could not find the gun. Two were salutes (actually one was color but with bottom shot) and the entire racks were disintegrated. No serious injuries in any of these but it is very sobering. Having a shell ignite while building is an even scarier thought. Hence, I seek advice when I am unsure.

[Peret]

Chlorate/sulfur mixtures have caused very many accidents in firework factories, even unintentionally, as when chlorate stars ignited on trays that had previously held sulfur-containing compounds. I believe it's universal practice now that chlorates and sulfur are handled in entirely different buildings to avoid such accidents. Chlorate stars without sulfur have their hazards but are still frequently used in Class B devices, though never for consumer products. I certainly would never make a chlorate/sulfur compound, or even one with a sulfide, but I make a few chlorate stars, mainly greens with barium chlorate, which I prime with a sulfur-free perchlorate prime.

[50AE]

By the way, I have a two years old mixture of potassium chlorate, barium nitrate, sulfur and dextrin. I was stored uninntentionaly, laying on a newspaper. Nothing has changed - look, or smell.

And what about match heads? My best friend has a big cardboard box with 40 year old matches. Don't the match heads contain sulfur, Sb2S3 and chlorate?

Edited September 30, 2011 by 50AE

[cogbarry]

There is an inherent danger in building fireworks, so do not believe that you are free to go about using perchlorates without care, but yes, they are safer than chlorates. A reaction between perchlorate and sulfur that would cause spontaneous ignition is not at all likely, but it should still be treated with respect as all compositions should.

 

 

Now onto the point of this topic:

 

 

If you are using chlorate stars, why use a sulfur containing burst? You're already using chlorate so you may as well use H3 on hulls and avoid any incompatibility. Priming with black powder or sulfurless BP is an unnecessary step since chlorate stars almost never need to be primed. You need to do something extra either way you think about it, whether you make H3 on hulls, or prime the stars, so why not use H3 and keep sulfur out of the shell entirely. Yeah, sulfur's not as huge a danger as it's made out to be, but it is still an added risk. If you don't need to use sulfur in the stars for a very specific effect there's no reason to have it in the shell at all. Just how I see it.

 

Thanks, I appreciate your advice and I see there are other options I hadn't thought/known of. I'm not familiar with H3 though for starters, but of course, I can change that. Also, I was thinking I needed the prime. If the star doesn't need prime, all the better.

Edited September 30, 2011 by cogbarry

[cogbarry]

Chlorate/sulfur mixtures have caused very many accidents in firework factories, even unintentionally, as when chlorate stars ignited on trays that had previously held sulfur-containing compounds. I believe it's universal practice now that chlorates and sulfur are handled in entirely different buildings to avoid such accidents. Chlorate stars without sulfur have their hazards but are still frequently used in Class B devices, though never for consumer products. I certainly would never make a chlorate/sulfur compound, or even one with a sulfide, but I make a few chlorate stars, mainly greens with barium chlorate, which I prime with a sulfur-free perchlorate prime.

 

Thanks,

I'm not interested in any chlorate/sulfur mixes either. I just see lot's of star comps with potassium chlorate and thought I'd try to learn the safety issues on using it and I knew there was a specific issue with sulfur. What is your sulfur free prime?

[cogbarry]

Chlorate/sulfur mixtures have caused very many accidents in firework factories, even unintentionally, as when chlorate stars ignited on trays that had previously held sulfur-containing compounds. I believe it's universal practice now that chlorates and sulfur are handled in entirely different buildings to avoid such accidents. Chlorate stars without sulfur have their hazards but are still frequently used in Class B devices, though never for consumer products. I certainly would never make a chlorate/sulfur compound, or even one with a sulfide, but I make a few chlorate stars, mainly greens with barium chlorate, which I prime with a sulfur-free perchlorate prime.

 

I think the accidents by definition are unintentional . Thank Peret, can I ask what you use for your sulfur free prime?

[NightHawkInLight]

Cogberry, try the miltiquote button next time you want to reply to multiple people.

[cogbarry]

Cogberry, try the miltiquote button next time you want to reply to multiple people.

 

Hmn,

Seems there's 3 ways to reply, one is in response to a specific user/comment. One is the fast reply. One is the regular reply which doesn't include any quotes and simply adds a global comment. I clicked the multiquote for this, don't see what the difference is.

[Mumbles]

Yes there are three ways to reply. The Fast reply just is a general reply. The post specific reply goes to the full editor with that post quoted. The multiquote button, when hit will turn a different color. Select the posts that you want to to quote all at once, and go to the full reply screen. The button to do that is at the bottom of the fast reply area where you can either post, or go to the full editor. When you go to the full editor, all the previously selected posts will be quoted.

 

Alternatively to do it manually, the [ quote ] XXXXXXXXXX [ /quote] tags will work. The series of X's is whatever text you want to quote. Just remove the spaces between the words and the brackets to make them work. The backslash is important in the second tag.

[cogbarry]

Yes there are three ways to reply. The Fast reply just is a general reply. The post specific reply goes to the full editor with that post quoted. The multiquote button, when hit will turn a different color. Select the posts that you want to to quote all at once, and go to the full reply screen. The button to do that is at the bottom of the fast reply area where you can either post, or go to the full editor. When you go to the full editor, all the previously selected posts will be quoted.

 

Alternatively to do it manually, the [ quote ] XXXXXXXXXX [ /quote] tags will work. The series of X's is whatever text you want to quote. Just remove the spaces between the words and the brackets to make them work. The backslash is important in the second tag.

 

Ah, Didn't realize I could then select the posts after clicking the multiquote button, thanks.

[Peret]

I think the accidents by definition are unintentional . Thank Peret, can I ask what you use for your sulfur free prime?

Oh, how embarrassing! I meant "unforeseen", as in taking chlorate from a barrel with a scoop that had previously been used for sulfur (6 killed, New Jersey), or sliding a box of chlorate stars on an apparently clean bench that had been used with sulfur comps.

 

My sulfur-free prime is derived from Veline's prime, which I used to use for everything once -

 

Potassium Perchlorate 55

Airfloat Charcoal 20

Silicon 10

Dextrin 5

Sawdust 10

 

Yes I mean sawdust instead of wood meal. I don't expect it to burn, I expect it to act like a packing material between the stars and cushion them during the launch setback.

 

Lancaster has some good information about chlorates and sulfur. He mentions that chlorate stars are usually primed with commercial meal powder and this apparently causes no problems. He identifies two dangers - chemical reactions that lead to spontaneous ignition, and friction that causes accidents in handling and launch. He mentions that you should always use distilled water when binding chlorates, as if there are calcium compounds in hard water they can react to produce unstable calcium chlorate. Prolonged dampness in the presence of sulfur, even sulfur dioxide from air pollution, leads to acid reactions. Friction is hazardous because the decomposition of chlorates is exothermic, ie it produces a small amount of extra heat so the reaction can run away. Barium chlorate is more hazardous than potassium chlorate because barium is a large and heavy atom that doesn't hold onto its ions so firmly as a light atom - I've heard barium chlorate described as a "fat man carrying two bowling balls", meaning it doesn't take much of a nudge to make him drop one. Lancaster says perchlorates are probably safer because of the molecular structure - a chlorate ion, with three oxygen atoms, is probably flat, whereas a perchlorate ion with four oxygen atoms is probably a tetrahedron and doesn't allow a sulfur atom to approach the chlorine atom.

 

50AE, while I agree the FUD about chlorates is overdone, the fact that you haven't had an accident - yet - is no guarantee that you won't have one next week. You shouldn't encourage others to be complacent.

[Potassiumchlorate]

The chlorine atom in perchlorates has a full outer valence shell, a so called "closed shell", whereas the chlorates have a chlorine atom with a "gap" in the shell. Edited October 1, 2011 by Potassiumchlorate

[50AE]

I intentionally mentioned the match heads, but it seems no one wishes to talk about them.

If the sulfur and chlorate comps were so dangerous, why are matches still being produced?

And what about friction igniters?

[Potassiumchlorate]

I intentionally mentioned the match heads, but it seems no one wishes to talk about them.

If the sulfur and chlorate comps were so dangerous, why are matches still being produced?

And what about friction igniters?

 

I agree with you. I have never heard of a sulfur/chlorate match that ignited spontaneously. Back when they had sulfur/yellow phosphorus in the matchheads, self-ignition actually happened, but that was over 100 years ago.

[cogbarry]

Oh, how embarrassing! I meant "unforeseen", as in taking chlorate from a barrel with a scoop that had previously been used for sulfur (6 killed, New Jersey), or sliding a box of chlorate stars on an apparently clean bench that had been used with sulfur comps.

 

My sulfur-free prime is derived from Veline's prime, which I used to use for everything once -

 

Potassium Perchlorate 55

Airfloat Charcoal 20

Silicon 10

Dextrin 5

Sawdust 10

 

Yes I mean sawdust instead of wood meal. I don't expect it to burn, I expect it to act like a packing material between the stars and cushion them during the launch setback.

 

Lancaster has some good information about chlorates and sulfur. He mentions that chlorate stars are usually primed with commercial meal powder and this apparently causes no problems. He identifies two dangers - chemical reactions that lead to spontaneous ignition, and friction that causes accidents in handling and launch. He mentions that you should always use distilled water when binding chlorates, as if there are calcium compounds in hard water they can react to produce unstable calcium chlorate. Prolonged dampness in the presence of sulfur, even sulfur dioxide from air pollution, leads to acid reactions. Friction is hazardous because the decomposition of chlorates is exothermic, ie it produces a small amount of extra heat so the reaction can run away. Barium chlorate is more hazardous than potassium chlorate because barium is a large and heavy atom that doesn't hold onto its ions so firmly as a light atom - I've heard barium chlorate described as a "fat man carrying two bowling balls", meaning it doesn't take much of a nudge to make him drop one. Lancaster says perchlorates are probably safer because of the molecular structure - a chlorate ion, with three oxygen atoms, is probably flat, whereas a perchlorate ion with four oxygen atoms is probably a tetrahedron and doesn't allow a sulfur atom to approach the chlorine atom.

 

50AE, while I agree the FUD about chlorates is overdone, the fact that you haven't had an accident - yet - is no guarantee that you won't have one next week. You shouldn't encourage others to be complacent.

 

Thanks Peret! I'm just reading this now and almost missed it. I was scrolling through and just found your response. That is great information, detailed and exactly what I was looking for. I will definitely try out your prime. I'm still pretty new but recognize the silicon. Is this prime itself easy to light or does it need an outer layer? I have used fence post in the past, I rolled a layer of meal over this, my friend didn't and his stars (the same comp) failed to light, mine were fine. In any case, I have all the chems and why not remove the sulfur from my prime. Thanks again for the help.

[Peret]

I've never had a problem with the prime lighting, just with the star underneath taking it from the prime. I found the silicon is a huge advantage here over the magnalium in many primes. Not only does it make a sticky hot slag but it doesn't make a white flare as it burns.

 

For really difficult stars I found this one never fails:

 

meal powder 20%

potassium nitrate 40%

silicon 40%

dextrin to taste

 

This will even ignite magnesium ribbon. It's gray, not black. Use a dust mask.

[cogbarry]

I've never had a problem with the prime lighting, just with the star underneath taking it from the prime. I found the silicon is a huge advantage here over the magnalium in many primes. Not only does it make a sticky hot slag but it doesn't make a white flare as it burns.

 

For really difficult stars I found this one never fails:

 

meal powder 20%

potassium nitrate 40%

silicon 40%

dextrin to taste

 

This will even ignite magnesium ribbon. It's gray, not black. Use a dust mask.

 

Wow! 40% silicon. Do you light this one directly as well? I'm not sure why my friend's stars didn't light when done with the same formulas as mine but I'm sure there are lot's of variables, chem qualities/suppliers, mesh size, mixing methods,etc.

 

Should I taste for dextrin after I add the barium nitrate and peris green or before? um um good! Thanks Peret!

[Peret]

It's apparently a military prime, published in Hardt. It lights just fine on its own thanks to the BP content. Your jest about barium nitrate and paris green is strangely relevant, as I always had trouble getting barium stars to ignite and that's the main reason I first tried this prime.