Hexamine is a Great Fuel

[Jonathan]

Hexamine is a hydrocarbon. A white crystal. It adds volume to flame and gaseous products when mixed with a strong oxidizer and an appropriate powdered metal. It turns an oxidizer-metal flash powder into a blowtorch.

 

A good mixture is NaClO4 + Mg + Hexamine. NaClO3 works well also, as does KNO3.

[Seymour]

Dude, Hexamine can, I believe, decompose giving off Ammonia.

 

You DO NOT WANT Ammonia and ClO3. Either someone prove me wrong or please be a lot more careful.

 

While for sure it has hydrogen and carbon, hydrocarbons are generally, I believe, substances with mostly just hydrogen and carbon. Think alkanes, alkenes ect. Hexamine is loaded with Nitrogen. The name gives it away, it's an amine.

 

You might be surprised by how many organic fuels turn a flash powder type mix 'in to a blow torch'. Hexamine is not bad. I think resinox is significantly better. It definitely burns way better than Hexamine when there are no metals there to 'give it a push'.

[taiwanluthiers]

Yea, it's a great fuel... in fact they work very well for camping in lighting woods. However you can't use it with chlorate. Edited September 23, 2013 by Mumbles
No HE discussion outside of the designated section

[mikeee]

Bill Ofca’s Technique in Fire

Bill Ofca covers some of these issues in his Technique in Fire series, and describes how some of these materials can be desensitized or properly treated to avoid spontaneous ignitions etc. This is a good resource for learning how to safely use some of the more hazardous materials and the safety precations needed when working with these materials.

[Jonathan]

Seymour and taiwanluthiers,

 

I've checked the reaction products of AP and Hexamine. They don't include ammonia. Neither do the reaction products of sodium chlorate and Hexamine. The reaction products are mainly CO2, H20, and N2; although the AP mix produces HCl, which is best avoided.

 

Everything I've read about Hexamine says basically that it's stable and relatively harmless. To get it to reduce, you need to ignite it at a high temperature (e.g., by using a good oxidizer and a powdered metal) or lower its ignition temperature (e.g., by using Hexamine as a fuel with an oxidizer such as KNO3 and phenolphthalein).

[hindsight]

Jonathan, thanks for answering my question to you about hexamine/ Mg (from another thread) here. Unfortunately, using it would be above my pay grade.

[taiwanluthiers]

Thing is out of the box hexamine smells like rotten fish... and ammonium chlorate is really bad for pyro. Even if the chances of hexamine reducing into ammonia is remote it's hard to say what could happen, and even a small amount of ammonium chlorate is bad news. However nitrate could reduce into ammonia in the presence of aluminum and water, so that could be bad if chlorate is present too.

[Jonathan]

taiwanluthiers,

 

Your points are well made. FWIW, here's what I consider far unsafer than some carefully studied experiments with a small amount of Hexamine and some potentially dangerous chemicals:

 

1) making a large batch (more than 10g for some mixes) of stuff that goes whoosh or whump

 

2) storing flash-type mixes

 

3) not doing my own research

 

4) screwing around with mixes verifiably proven to be friction or shock sensitive (e.g., Armstrong's mix)

 

5) taking anything in pyro chemistry for granted

 

Also, not that it means a whole lot, I've got an undergrad degree in electrical engineering, which involved a lot of lab work.

[Seymour]

No offense intended Jonathan, I don't intend to be argumentative but I disagree with some of what you are saying.

 

I've checked the reaction products of AP and Hexamine. They don't include ammonia. Neither do the reaction products of sodium chlorate and Hexamine. The reaction products are mainly CO2, H20, and N2; although the AP mix produces HCl, which is best avoided.

 

The products of the desired reactions is not what I'm worried about. Hexamine is made with Formaldehyde and Ammonia. In acidic conditions this reaction can be reversed. My worry is that either it was not made completely pure (though ammonia should be easy to remove since it is so volatile and Hexamine can be recrystallized) or simply in storage it has to some extent started to degrade, producing ammonia or some ammonium salts.

 

I'll admit that the risk of creating Ammonium chlorate is probably my favorite danger to get all paranoid about, and I'm not expert enough at the chemistry here to be 100% sure the risk is as high as I am making it out to be, but for sure Ammonium chlorate creation via double decomposition of Chlorates and many Ammonium salts in the presence of moisture is one of the greatest incompatibility issues we have to deal with in the manufacture of pyrotechnics.

 

I don't hesitate to say I'd much rather make a Chlorate/Sulfur mix than a Chlorate/Ammonium one. Not that I recommend either.

 

I have to say, due to this I definitely think your five points are not far unsafer than a potential chlorate/Ammonium mix.

 

While no doubt making fireworks is not a safe hobby, taking the fact that we do for granted, making 10g of a composition that can go whoosh or whomp is something most of us do very regularly and don't think much of it. Many of us do it by the kilo, or multiple kilos. Of course this brings us in to the level that an accident could kill us, while making a small quantity of a possibly dangerous experimental mix is not likely to kill if there are no other compositions nearby for it to set off.

 

In your context, which I assume is experimenting with less than ten gram quantities of explosives and not storing them, what you say is perfectly valid. However a lot of us build serious fireworks and there is no way around having a lot of compositions made and stored if you make a 6" shell. For those of us that do, any mixture that could spontaneously ignite is, in my opinion, a complete no-no. This is taking the fact that we have much more than 10g of the good stuff mixed up and stored for some time as a given.

 

Properly stored, any sensible flash powder is just not going to go off in storage. While again, storing flash is not recommended, and making minute quantities of highly sensitive explosives is not any real threat of serious injury (so a real risk like having a kilo of BP will of course be more dangerous by this reckoning), the fact is that many of us do. In the context of us making large fireworks this is not in my opinion an unacceptable risk. I'm now starting to repeat myself, but given the fact that many of us do have a fair bit of live pyro in the workshop, adding any of these 'possibly dangerous chemicals' is a completely different risk than it is to just have these 'potentially dangerous chemicals' in a sterile lab.

 

I'm happy to screen together five kilos of KP/Al flash, but I don't like chlorate being present. Too many incompatibilities, and the fact simply is that I work around an awful lot of live pyro. Not the safest thing, but it's the hobby/job I have. I want to make fireworks, lots of them, and often big ones. In different situations the acceptable risks may be different. I'm sure a lot of people consider pyrotechnics manufacture on this scale is an unacceptable risk in it's self, but for me it's a given. Day to day life.

 

I'm not sure what you mean by 'not doing my own research'. I cannot say that doing your own research is a bad thing. Of course, it is vital. Nor am I saying that all research is theoretical, but considering the risks I think that, a hell of a lot of theoretical research needs to be done before getting in to the practical side of things. Like you seem to, I like to test new and exotic materials that no one or very few people have made before. For several years I stuck to KNO3 compositions before I got my hands dirty with more dangerous oxidisers, by which time I had clocked hours reading about the topic numbering in the low thousands. I think that is the way it should be. I definitely don't think you should rely solely on other people's research, but there is a saying I am sure you have heard.

 

"A smart person learns from their own mistakes. A wise person learns from the mistakes of others". I think it has some validity here.

 

I am not saying you have not read enough. I have no idea how much time you've spent reading, I'm just discussing the points. Also, it might make more sense if you take some of my grumpy sounding posts as a reply to all readers, particularly new ones, not just yourself. Being a public forum I feel this is necessary.

 

"taking anything in pyro chemistry for granted" I really don't get what you are trying to say here. Maybe you are pointing out the quantity of misinformation out there? There certainly is a lot said that is plain not true. This is why I'm trying to make it clear that I don't know quite how serious the risk of Hexamine/chlorates is. However I know enough to see that there is potentially a severe risk. As such I feel compelled to point it out. I would like someone to prove me wrong so I can shut up about it (you are not the first one I've warned about the issue) or prove me right so I have some reference to point to.

Edited September 24, 2013 by Seymour

[Jonathan]

Seymour,

 

No offense taken at all. I like your thoughtful response. And after all, the U.S. and N.Z. are good allies.

 

By "doing my own research" I'm reflecting my undergrad education in electrical engineering. By "not taking anything for granted in pyro chemistry" I reflect, for example, upon dagabu's post in some thread to the effect that two rockets made the same way can perform quite differently. Pyro chemistry is, from what I've observed surfiing the internet, as much art as science. In a scientific experiment, one knows going in what to expect, because all the variables are known. In a pyro experiment, one does not know all the variables -- unless one is a scientist in a carefully controlled lab.

 

I happen to agree entirely that it is important to learn from mistakes. The best free learning comes from learning from others' painful mistakes.

[hindsight]

Articulate, civil, enightening and awe-inspiring. Jonathan and Seymour, while I know precious little about the chemistry of pyrotechnics (my undergraduate study in chemistry has been little used in the last 40 years since it's completion), I do know a bit about dealing with high-risk, life-and-limb situations and I am sincerely impressed with your summation of a great deal of wisdom--in such an unanticipated place-regarding empiricism and reality. The nature of of what we can know, sorting out relevant variables, taking risks, assigning value to an experience...these are topics that confound philosophers, theologians, dreamers and ...well...hobbyist pyrotechnicians. Thanks. I continue to follow your posts, as much for the pyro knowledge as for your mature opinions on grander matters.

[Jonathan]

hindsight,

 

Seymour provided very valuable information re resinox (phenolic resin). I look for teachers.

[Pyrog]

How can I get Hexamine?

[hindsight]

How can I get Hexamine?

Pyrochemsource.com, Ebay, etc.

[NeuroticNurse]

How can I get Hexamine?

 

Ebay for instance, its the cheapest stuff. I've gotten a few tablets from camping shops as fuel tablets.

 

 

THat was a top post Seymour.

[flying fish]

I've checked the reaction products of AP and Hexamine. They don't include ammonia. Neither do the reaction products of sodium chlorate and Hexamine. The reaction products are mainly CO2, H20, and N2; although the AP mix produces HCl, which is best avoided.

 

This also caught my attention. Ammonium Perchlorate (if that is what you mean by AP) should not be used in the same vicinity or with the same tools as chlorates. Most people don't have two sets of tools and two separate work areas, so most people do not work with both...