29 replies to this topic

[Mumbles]

The problem with boron enlies that the common green we see in alcohol solutions is thought not to be as a result of boric acid, rather borate esters. As such, putting it in a composition will not yield the same effects. Boron Oxide is quite hygroscopic and reactive with water, probably pretty exothermic too. If you are thinking about adding just borate esters, the good coloring ones are all liquids, and decompose even at blue flame temperatures. As previously brought up, there might have some luck with NC based compositions. You'd probably have to use boron powder, which is pretty expensive, even for small scale experimentation.

[phildunford]

Frankly speaking, you seem keen to test all kinds of pesticides, way more harmfull than barium salts, but you are afraid of barium. Seems a bit odd to me.

Don't want to be picky, but I would observe that many of the Barium Salts we regularly use are FATAL in quite small doses - don't think you can get much more harmful than that!

[digger]

Don't want to be picky, but I would observe that many of the Barium Salts we regularly use are FATAL in quite small doses - don't think you can get much more harmful than that!

This is true.

However for example Toxaphene is lethal at much smaller doses than soluble barium compounds and is more easily absorbed through the skin, Heptachlor is more toxic than Toxaphene (although not such a problem with skin contact), Dieldrin banned worldwide due to its persistence in the environment, buildup in the food chain and toxicity (hard to destroy also). Although a couple of the products listed are just mild irritants to humans they would appear to have little interest as chlorine donors.

So for a few of the chemicals listed a lung full or two of dust could be a serious problem that does not go away quickly like mild barium poisoning does (it does not bio accumulate like many of the pesticides mentioned).

I am not "dissing" the quest for new products for pyro uses as I have said earlier in the topic, in fact it is great that people are looking to try new ideas. I am just saying a little more research on some of those chemicals mentioned should be done before using them (I would also be surprised if it is actually possible to obtain some of them at all from legitimate sources).

[fruitfulsteve]

I would be very surprised if this hasn't been tried, but what about pool chlorine tablets ? i tried looking them up to find the chemical formula, but just got a long list of companies that sell them. I suspect they are sodium based so not much use unless your making yellow/orange stars, but i can't help thinking that perhaps you could replace the sodium with potassium ?

or have i just reinvented potassium chlorate or potassium hypochlorite ?

[Mumbles]

I've seen three chlorination products. One is calcium hypochlorite, and is hardly pure. There is a pretty significant proportion of calcium hydroxide. Another is Trichloroisocyanuric acid, sometimes called TCCA, Trichloro-S-Triazinetrione, or trichlor. The other is dichloroisocyanuric acid, which is usually sold as a sodium salt.

Of the three, obviously Trichloroisocyanuric acid is the only reasonable option. However it is unstable in water the last time I checked, forming a bleach-like compound. Honestly, I think they're too reactive and unstable for any real use. Storage stability would be an issue, and it does generate some pretty reactive species which could lead to bad outcomes. TCCA does have 90% chlorine though.

Something to look into might be chlorendic acid, or it's esters. It is a precursor to many of the nasty pesticides above and probably isn't that nice itself, but it is still produced industrially for various flame resistant additives and polyesters.

[MDH]

Yes. That is just hypochlorite. It decomposes into chlorate over time. There is not much you can do with it in pyrotechnics. Even compositions deliberately sensitive (such as snaps) would degrade over time.

Last night I was looking at purchasing chloranilic acid from a chemical supplier. It will cost a lot of money for just a 25 gram sample, but it certianly does look quite appealing.

Trichlorophenolates are also available as solid, stable salts.

[fruitfulsteve]

Not really viable for a 8" shell's worth of stars then!

[Mumbles]

I don't think chloranillic acid would have nearly enough chlorine to be useful. Even TCCA is questionable in this regard. The real good stuff would be deca-chlorodiphenyl ether, or other highly chlorinated diphenyl ethers, or diphenyl methane, even pentachlorophenol. All of the above are of course kind of hard to get.

[Arthur Brown]

If you do the Kosanke's pyrotechnic chemistry course or read their book you will find several clues for mechanisms of colour development in flames of various temperatures. The book does pop up on ebay and on some American pyro sites that sell books. Also it can be found on Abebooks.co.uk or on the dot com site. Reliable pyro books are not cheap.

[Mumbles]

Some would also argue that the Kosanke's produce reliable pyrotechnic literature. They have quite a bad reputation in the pyro community for faux-science and being government sellouts by testifying for profit against many pyrotechnists. Now, their journal and literature has pieces by many more well respected individuals, which I am sure are excellent. I am just wary anytime I see their name attached to something.

[fruitfulsteve]

The pool chlorine tablets etc maybe a good source of Chlorine gas which could be passed over/through say dextrin, red gum and even some organic acid fuels. I'm not suggesting anyone rushes off to try this as mixing pure chlorine with anything especially organic fuels could be rather dodgy, but it might be worth looking into.

Would sulphur and chlorine form a compound ?

[Mumbles]

Just passing chlorine over those things wouldn't do anything really. You'd want to dissolve them in a solvent (carbon tetrachloride is always a popular choice), add a chlorination catalyst, and then bubble the chlorine through. FeCl3 and AlCl3 are highly tauted chlorination catalysts. Don't forget the reflux condenser because it's going to be exothermic. Properties will be changed as well. If you're going to do Dextrin or other carbohydrates, you might as well try using sucralose before dealing with chlorine gas. Very low chlorine content though.

Sulfur and Chlorine in fact form a compound, both liquids. Sulfur and chlorine form the red fuming compound S2Cl2. Upon adding more chlorine, you get the yellow SCl2. They are excellent chlorination agents, and might be better suited and more controllably used than the above method. There is a way to convert it into SOCl2, Thionyl chloride, still a liquid but again a good chlorination agent. If you want to get exotic like this, you may want to try phosphorus instead of sulfur. It forms solid PCl3 and PCl5. Unfortunatly anything organic it touches, or water, or air, is going to result in excessive fuming and probably a fire.

[a_bab]

PCl3 is a liquid at room temperature and it fumes like hell. Very corrosive and so on. As someone I saw it, I'd never consider it a s a chlorine donor".
Interestingly enought, CCl4 is acually used to make parlon; just soaking natural rubber with cab tet will render parlon in certain conditions. That's why parlon always contains a small amout of carbon tetrachloride and the reason will be probably phased out. It is used extensively in the paint industry as a base.

As about pool tablets and such, I never can't see these of any use in pyro. Maybe as an exotic compound like "make it and light it or else in 5 minutes will spontaneously ignite/turn into a mulch due to water absorbtion"

[fruitfulsteve]

Owell it was just a thought.

[MDH]

As I said before, we could easily turn to the chlorination of soluble carboxylic acids. Generating chlorine gas to bubble through a solution is quite easy.