Potassium Permanganate

[KevFla2001]

Hello Members..

Can anyone tell me EXACTLY what the problem is with using Permanganate for flash compositions? I'm very familiar with Perchlorate, Chlorate, and Nitrate, and know the precautions about each of them.

The problem is I can't seem to find out exactly WHY permanganate is consistantly listed as "not advised" and "unstable".

If anyone can direct me to reliable information on this I would be very grateful.

Thanks

Kev

[justanotherpyro]

The reason it is frowned upon is because chemically it is more unstable than the other oxidisers that are available. Just because you havn't had an accident doesn't mean that it is safe. I'm sure there are people that have stored TATP for years and have not had any problems with it, but that doesn't make it safe by any means.

 

You're right though, it is useable and with certain precautions it is perfectly acceptable for use. The main issue about its use is the fact that there are much safer alternatives. Again, the age old rule applies. Don't be stupid with dangerous substances.

[rocket]

KMnO4 as it stats in the wiki page is a powerful oxidize and any power oxidizer is dangerous in it on way its just that KMnO4 incompatible with a lot more chemicals also it not good for your health its believed to be a caseinogen(sp) IIRC.

[KevFla2001]

Dear Members

I AM familiar with all those responses, and Squibb, I too found the Wiki site in two seconds, several months ago. Unfortunately it states absouletly nothing about WHY Permanganate is considered "unstable" and "not recommended" for flash compostion. I have been searching the internet for months now and can't find a scientific reason for the negative recommendation concerning Permaganate.

 

We all know the Chlorate/Sulfur combiination breaks down over time to produce Sulforus/Sulfuric acid which produces Chloric acid, which ignites Chlorate. Therefore, "not recommended" and "unstable" absolutely applies to this composition.

 

But once again, WHY Permanganate? And please don't repeat what you have read about sulfuric acid drops, sugar, water drops, ect ect...

What I'm looking for is good hard scientific fact as to the reasons why Permanganate is getting the bad rap.

Thanks again to all who can help me find this information

Kev

[optimus]

If you mix a few grains with some powdered sugar and (carefully) expose it to friction you will see why. It also degrades with storage and quickly becomes even more useless.

[Chemguy]

Well, I would say that it is because aswell as having the oxidation no. +7, it also has a tendency to find the fastest reaction path. As you know MnO2 is a catalyst for many things, e.g. the decomp. of H2O2. So KMnO4 reacts much better with some chemicals because it has an almost 'inbuilt' catalyst. Again with H2O2, it will catalise the reaction of it, and react itself. This does not mean that it reacts well with everything though I don't think that Mg reacts well with this particular catalyst. So KMnO4 has a lot more incompatibilites, but works well with the right chemicals. I hope this helps .

[styropyro]

Another reason why it's so unstable is the classic permanganate/glycerine trick. You drop some glycerine on it and it lights right? Try the same with Potassium Perchlorate, a fairly powerful oxidizer. You can mix it all you want and even put a wick in there and most likely you won't get it to light. That shows how powerful permanganate is and ready to combine with other materials (when you don't want to.)

[Blaf]

Hello guys

 

I feel strong impulse to react to this topic. I've been using this proscribed chemical for years now and I'm really talking years because I,ve got a glass yar of KMNO4 for more than 20 years now and it's still as fresh as it was when I bought it. I have it tightly closed with addition of small bag of silicagel granules. That much about its storage.

But since consumer fireworks are being available for last 15 years in my country (don't ask...), this valuable reserve of my beloved oxidizer became obsolete. Anyhow, from time to time I mix small quantity of Perm, Alu and S, just for a fun of it. And it still works fine. That much about its shelve life.

As description to its friction sensitivity, I have a short story. Long time ago I made a few crackers, rather big ones for nowadays taste. Fuse was not available at that time and I used sparklers instead. Two of those gone off loudly but third one would not explode! It wouldn't catch fire at all! OK, we placed foulty cracker on a solid rock, topped it with another one and searched for suitable boulder to hit the whole setup from above. You probably expect to hear that my cracker went off just like that, without additional force, right? No, it did not happen. We found a really big piece of rock, I took it above my head and left it to crash into upper rock. Nothing happened but cracker was deformed beyond recognition. I repeated it again, this time harder, with no success. Third time I got mad and slammed it so hard that my boulder crushed into several pieces...and my cracker finally went off! So, lets make conclusion – it takes far more than simple friction to set this thing off.

Of course, you shouldn't mix it with glycerine and keep it in your shirt pocket – we all know it will ignite spontaneously. But if you make small quantity of flash with it, I won't say a word.

Wait! I'm sure I've got a certain quantity of KMNO4 flash already mixed, stored in small brown-glass yar waiting to be used. As far as I can recall, it's mixed back in 80s...

So, what's the teaching? If you can't get Perchlorate, use your Perm flash without much fear. Be moderate and nothing bad will happen...

 

Blaf

[Mumbles]

I would just like to point out to people reading this to take blaf's reponse with a grain of salt. I think this quote gives all the reason.

 

Wait! I'm sure I've got a certain quantity of KMNO4 flash already mixed, stored in small brown-glass yar waiting to be used. As far as I can recall, it's mixed back in 80s...

 

I personally wouldn't take advice from someone storing flash is glass jars. Thats just me though.

 

Blaf, please stop giving unsafe advice. "If you can't get perc, use permanganate with no fear" is not the right attitude. Permanganate is notious for being unstable. Then again anyone thinking storing flash powder in glass is safe, probably doesn't have their head on quite right in the first place.

 

 

 

As to why it is unstable, it just is. The bonds of the ion are stressed, and are higher energy bonds. The manganese most definatly doesn't want to be +7. It's most stable form is +4. It will give up those electrons anyway possible.The sugar thing is very true by the way. It will ignite/react by friction. Try mixing it together and adding a few drops of water, also will start reacting. Upon addition of water, it is slightly hydrolysed into Permanganic acid, which hates pretty much everything, and is very explosive. Another reason not to use it is that itself is quite poisonous, but also the smoke will be poisonous. Manganism is not fun times I assure you http://en.wikipedia.org/wiki/Manganese_poisoning

 

As for the MnO2 thing being it's own natural catalyst, I don't think it really applies here. The main things it is mixed with is metals and/or sulfur in pyro. What's it going to do, catalyse the decomposition of the metals? MnO2 doesn't catalyse the decomposition of sugar either.

[Chemguy]

It is true about manganese wanting to be at oxidation state +4.

But chlorine doesn't want to be there way up at +7 when normally it is at -1. The same for all the other oxyanions of chlorine. However the fact is probably correct.

About the inbuilt catalyst, I guess what I failed to say properly is that it finds fast reaction paths, due to the fact that for one the MnO2 is a catalyst but this doesn't apply here, also the fact that you said - that it is unstable and wants to break down into MnO2 and K salts.

 

 

Also storing flash is not a good idea, I made a few grams of Al permanganate flash to see if it was dangerous when it lit, I was careful, the Al was low mesh though. It burnt quite slow but the heat was so intense that it melted through the steel thing it was in. I don't intend to make it again, as I don't like making flash due to the dangers, which were made clear by this demonstration. Imagine what flash would do in a glass jar. If it was even a few grams, I wouldn't want to be anywhere near it. It is friction sensitive too. Anyway, the message is permanganate is not good for flash.

[KevFla2001]

Dear Chemguy and Mumbles

 

Thanks for your posts. Your information is very informative and your advice concerning Permanganate should be well heeded.

 

My original post was about Permanganate flash compositon, KMno4, Al, and, or not, S, and why this combination is frowned upon.

 

Health hazard yes, but so are many of the chemicals used in pyrotechnics.

 

Reactive yes, like many other chemicals in Pyrotechnics, although for such a reactive chemical I can enter my local builder supply chain and buy all the Permanganate I can carry.

 

Doesn't play nicely with many other chemicals? Yes, although I'm only interested in 2 chemicals, Al and or not, S.

 

With all due respect, the purely technical question is "exactly what is the problem with Kmno2 based flash". Kmno4, al, s. Not water, sugar, glycol, sulfuric acid and a whole host of incompatables too numerous to be listed here.

 

I agree with both of you guys. There ARE WAY BETTER compositions!! No argument!! I just need to satisfy my scientific curiosity concerning Permanganate flash.

Thanks

Kev

[delta_echo]

While they may not have blatantly answered your question, they more than described the situation surrounding the inquiry.

 

KMnO4 is unstable by itself a very strong oxidizer. Al is reactive as well, usually not to the extent of Mg, but in flake form will react quite readily with an oxidizer.

 

Think about it. You just combined something that has a chance of spontaneously decomposing with a high energy fuel. This equals a large amount of energy released at a possibly inopportune time. So much so that normal manufacturers have forgone use of it. Has it been used safely? Yes, but so has Armstrong's mixture, called death mix for a reason.

 

Furthermore, I don't know your source of permanganate. Even so - while lab grade is far less likely to suffer from the problem - unknown contaminants are in the mixture and therefore quite possibly in the crystal lattice of the permanganate. These small impurities act as "site of reaction" which make the permanganate even MORE reactive.

 

The choice to use permanganate is, of course, yours. If you wish to pursue it, I would suggest not making more than a gram at a time (that way you won't lose more than a finger or two). Most of us on the board have learned the hard way about safety. I personally gave myself 3rd degree burns on my chest and nearly burnt down my home with a KNO3/Sucrose smoke mix when I was young. Looking back, I was lucky to have learned such a hard lesson about the reasons for safety with such a "tame" mixture. I hope you never have to experience such pain and can learn now. I'm not talking down to you or anything and I don't pretend to know your experience. You just seem hell bent on making the stuff judging by your posts.

[Chemguy]

delta echo summed things up nicely, it's true. Really there is no more reasons about KMnO4 flash being unstable, that's it.

 

I learnt my lesson through KNO3 Sucrose to. I let it off in my garage, about 200g. God that was dumb, but anyway, if that had been the KMnO4 flash I wouldn't be here here, atleast with as many limbs as I have now.

[oriansbelt]

delta_echo I don't think he wants to make it(atleast from my impression of "I agree with both of you guys. There ARE WAY BETTER compositions!! No argument!! I just need to satisfy my \\scientific curiosity// concerning Permanganate flash.") He just wants to know WHY it is shunned.

[Mumbles]

Chlorine has unfilled D level electron slots for which to make bonds with, which makes the bonds somewhat more stable. Perchlorates are more stable than Permanganates, that is a pretty standard fact.

[Chemguy]

I know that perchlorate is more stable than permanganate. Isn't chlorate more unstable then perchlorate? I guess chlorine doesn't like the +5 state. Also I did some reading about manganese and apparantly it's favoured oxidation level is +2, this makes sense because in science (chemistry) MnO2 was classified as an oxidizer, as it wants to be +2 not +4.

[KevFla2001]

Thank you Oriansbelt!!

 

I'm glad at least one person here understands me!!!

 

I think Chemguy and Mumbles do too, to a certain degree anyway. It's the SCIENCE of why it's not recommended that I'm after. What are the reactions taking place and so forth. It's just a discussion about what makes Kmno4 consistantly "not recommended".

 

Thanks to Chemguy and Mumbles who are definately going in the right direction on this and enlightening me with every post.

Thanks to all,

Kev

[delta_echo]

Thank you Oriansbelt!!

 

I'm glad at least one person here understands me!!!

 

I think Chemguy and Mumbles do too, to a certain degree anyway. It's the SCIENCE of why it's not recommended that I'm after. What are the reactions taking place and so forth. It's just a discussion about what makes Kmno4 consistantly "not recommended".

 

Thanks to Chemguy and Mumbles who are definately going in the right direction on this and enlightening me with every post.

Thanks to all,

Kev

Hmmm. While I'm glad you're getting something out of all this, what I hope we all are learning here is the value of asking specific questions. If you want reactions, ask for them. The term "science" is overly broad. I could give you reaction mechanisms, but they are of limited value and, as no one can physically see an electron transfer (only the indications of it), it is all theory. For matters of pyrotechnics, it is of no use I know of.

 

And I apologize if I misunderstood - this hobby is plagued with people who have no desire to develop beyond flash.

[pa_pyro]

Like delta stated you should be more specific about what information you want. It seems everyone has stated all of the reasons for this being an unstable oxidizer. If used within a short time of being made, flash made with KMnO4 is fairly good at breaking small shells and things like crossettes that need a powerful mix to properly break. For anything larger than 1 or 2 inchers I would stick with proper 70/30 perc/Al. With KMnO4 or other flash mixes I wouldn't go adding sulfur, flash is already sensitive enough.(the only case I go against this rule is if I make bright flash with spherical aluminum. My bright flash comps don't seem to light unless I add few parts sulfur.

[ltf]

In my country you can't get perc. so we often use KMnO4 for flashes, it's not so dangerous if treated like TATP or other unstable substances..

But if you do have the option of not using it, just don't, it's messy, and doesn't worth the risk..

[Chemguy]

But if you do have the option of not using it, just don't, it's messy, and doesn't worth the risk..

 

My god is it messy. I was using some yesterday and I spilt a tiny amount of powder onto the bench, I cleaned it of with a towel, then got a wet cloth and wiped it, the wet cloth is now a dark purple colour that is falling apart. The KMnO4 is going brown now slowly as it oxidizes other chemicals that may have got on the cloth and the cloth itself.

[serval]

Can u make any good gunpowder from kmno4. I have no KNO3.

[Chemguy]

Not as good as the normal recipie, it more dangerous too. Read the thread!

[Wiedras]

im making rockets with AP reports. 0.5g of Ap make respectable report. i know its crazy, but im working with AP for years and there wasnt any accidents. if you know what you do there are no problem.

[Chemguy]

err.. Why is this in here? Ap is refering to acetone peroxide trimer right... Firstly this should be in rocketry, and AP is a HE, which doesn't belong here. I suggest you reasd before you post.