8 replies to this topic

[RegimentalPyro]

Here's one for all you pyro's who are loath to open that tub of Barium Nitrate for fear of toxicity. Using Boron Carbide to produce good green colours.

http://www.nature.co...s.2011.222.html

The thought of a green alternative to Barium greens is a tempting one, but a short bit of research on t'internet shows a fairly high price on this substance, more usually used in industrial grinding applications.

Anybody else get a better price than £200 / kg for a finely powdered version of this stuff?

[dave]

Here's one for all you pyro's who are loath to open that tub of Barium Nitrate for fear of toxicity. Using Boron Carbide to produce good green colours.

http://www.nature.co...s.2011.222.html

The thought of a green alternative to Barium greens is a tempting one, but a short bit of research on t'internet shows a fairly high price on this substance, more usually used in industrial grinding applications.

Anybody else get a better price than £200 / kg for a finely powdered version of this stuff?

interesting article.
i wonder what it does to friction sensitivity of the mix, i would guess it would increase sensitivity

dave

[Mumbles]

They actually address the sensitivity, and it appears that because the particles are so fine, there is little risk from friction. Additionally, the chemicals are added separate to the binder and blended wet.

[digger]

I did a quick search and in tonne quantities it is around £12 per kg, so still double the price of barium nitrate.

In smaller quantities around 100kg it is around £20 per kg

Edited by digger, 13 April 2011 - 11:08 PM.

[Mumbles]

It's not like it'd be cost effective to get it from you, but what size is the material you were looking at? The stuff in the paper uses a material finer than 10 micron. A larger variety was available from the same supplier, which is essentially what we could consider -325 mesh for all intensive purposes. I bet that would work fine as well. It'd be nice to make a green from just two chemicals, when one of them is potassium nitrate.

It should probably be noted before people get too excited that these are flare compositions, not stars. I believe they burn around 8 seconds for a 1/2" pellet. The control was a barium nitrate/PVC/coarse Mg type flare composition. It had a similar emission spectra, but the images and data made it look fairly washed out, centering around a yellow-green that I would more appropriately assign to BaOH instead of BaCl.

[Creepin_pyro]

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Edited by Creepin_pyro, 08 October 2011 - 10:10 PM.

[Mumbles]

I haven't seen a good price on amorphous boron, so I'm not sure. One US seller retails it for $40 an ounce. That means it probably sells for around $100-150/lb on the realistic market. Given even this price I'd save it for only e-matches and specialty delays.

I really wasn't thinking earlier. The downside to amorphous boron in the paper is that it burns too fast for flares. This means to us that it burns perfectly for stars. I think it was between 2 and 3 seconds for a 1/2" pellet.

[Potassium chlorate]

Boron is interesting, but if you use it because you're afraid of barium, you shouldn't be a pyrotechnician in my humble opinion.

You will never get a better green than from barium chlorate anyway.

[Potassium chlorate]

Sorry if I was rude. I sometimes am, but if you wear protection, barium shouldn't be a problem. Barium sulfate would do for anyone; it is used by X-ray of the stomach, so you can even eat it. It might need lots of metallic fuel to make a good green, though.