33 replies to this topic

[Strobe]

Hi,

Does anyone have any experience using chlorowax as a chlorine donor. I searched the archives and didnt find much though creepingpyro listed it as one his favorite chemicals. Its relatively cheap compared to parlon. I'm curious how well it works and if its generally easier or harder to use than PVC or Parlon.

My second question is how you would convert a formula to substitue in a different chlorine donor.

For instance if a formula called for:

Barium nitrate....................................80
PVC...............................................10
Red Gum...........................................10

But I wanted to substitute chlorowax as the chlorine donor.

Would it be something like dividing the %chlorine contributed from the PVC (57%) by the % chlorine contributed by Chrolowax (70%) to scale the amount needed?

ie .57/.70 = .81 and then multiplying the 10 parts PVC in the formula by .81 to get the proper amount of Chlorowax to substitue for PVC?

.81 X 10 parts (PVC proportion from the original formula) = 8.1 parts Chlorowax required to substitute?

I'm not sure if I've done the math properly or if its as simple as determining a ratio.

[pyrotrev]

Yup, can't see any fault with your sums there. You should of course remember that the "missing" 1.9% in the PVC was in fact carbon/hydrogen i.e. fuel, so it might be wise to increase the amount of red gum by the same amount to keep the heat output up.

[Strobe]

Yup, can't see any fault with your sums there. You should of course remember that the "missing" 1.9% in the PVC was in fact carbon/hydrogen i.e. fuel, so it might be wise to increase the amount of red gum by the same amount to keep the heat output up.

Thanks Pyrotrev. It hadn't occured to me consider the non-chlorine part of the chlorine donor as contributing as a fuel.

Judging from the lack of responses on the chlorowax question, I guess its not in very wide use.

[pyrotrev]

If it's 70% chlorine it ought to be a good donor -- I'd be interested to know about it's properties and availablity. I suppose if it is actually waxy it might be a slight problem to use (you'd need organic solvents), hence the lack of popularity?

PS should this thread be in the Pyrotechnic Chemistry section perhaps?

Edited by pyrotrev, 29 May 2007 - 02:26 PM.

[Strobe]

I'm curious about the consistancy as well. Here's what the website that sells it says:

(Chlorez 700, chlorinated paraffin resin) Cream colored powder

Used as a chlorine donor (70% chlorine). -50 mesh, 97%. Solvents are xylene, acetone and alcohol.

It runs about $8.50 US which is a lot cheaper than Parlon, but the only formulae I see using it are the Baechle system ones, which also use a couple of things I dont have like copper oxychloride and stearic acid. So maybe there isn t much point in buying it to save money.

Sorry, your probably right about this wanting to be in the Pyro chemistry forum but I'm not sure how to move it.

[karlfoxman]

Moved, please carry on discussion.

[dr thrust]

hi, sorry for being a "newbe" i,ve bought myself some powdered pvc for a chorine donor, my question is how does the chlorine bring out the "colours? any boffins out there!!

[pudi.dk]

I am not stable at this point since I havn't experimented with coloured stars yet,
but I think the reason is that the chlorine turns the metal salts into chlorides which burns with a much clearer flame,
whereas using chloride salts will be too hygroscopic.

Am I totally missing the nail with the hammer?

Edited by pudi.dk, 18 July 2007 - 11:04 PM.

[portfire]

It is the chlorides present in flames yes,for example,when strontium and chlorine are present in a flame they bond together to form molecules (strontium monochloride) which give off the red light or photons,due to the atoms been excited,but the molecules dont give off red light,the light is reflected (bent) to the red part of the spectra.

I'm sure someone out there can give a more in depth explanation than i can,and please correct me if im wrong on any points.

dean

Edited by portfire, 19 July 2007 - 07:30 PM.

[dr thrust]

thanks guy's that answers my question,ps how the hell do you know all about a that?

[digger]

It is the chlorides present in flames yes,for example,when strontium and chlorine are present in a flame they bond together to form molecules (strontium monochloride) which give off the red light or photons,due to the atoms been excited,but the molecules dont give off red light,the light is reflected (bent) to the red part of the spectra.

I'm sure someone out there can give a more in depth explanation than i can,and please correct me if im wrong on any points.

dean

If I remember my Physics, you are not far from the answer, however I am not sure about the light is bent bit as the molecule does not have enough mass to bend light and I think you could probably rule out refraction, as the gaseous mass/density of combustion products of coloured pyro mixes probably does not vary enough to account for the different colours.

I would imagine it will be due to an electron moving between energy states in the chloride salt molecule. This is due to the electron being excited by the heat and moving into a higher energy orbit further from the nucleus such that when it drops back into a lower orbit a photon of light is emitted. This photon of lights frequency (read colour) is dependent on on exactly which electron orbit levels the electron moves between. Hence metals with different masses will have more or less electrons giving rise to a move between different orbits hence different colours.

Anyone have any more to add?

Edited by digger, 19 July 2007 - 10:24 PM.

[BrightStar]

Yes, it's the molecular spectral emission of the excited metal chlorides. These tend to emit light in narrow bands of visible light and so give the best colours.

In addition to their light emitting properties, the chlorides are volatile, so having chlorine available for their formation ensures that there are plenty of colour emitting molecules vaporised in the flame.

A secondary effect of adding a chlorine donor to magnesium fuelled colour compositions is explained by Shimizu. The solid MgO particles in the flame emit white light by hot incandescent emission. Having hydrogen chloride in the flame converts some of this to volatile MgCl, so reducing the white light and enhancing the purity of the desired colour.

In the 'good old days' Weingart mentioned using Mercury (I) Chloride (Calomel) or Ammonium Chloride (Sal Ammoniac) as chlorine donors for greens and blues. The former was toxic and expensive, the latter too hygroscopic for anything but immediate use. Since Ammonium Chloride is readily available it might make an interesting experiment - just not with Chlorates ...

Edited by BrightStar, 19 July 2007 - 11:12 PM.

[Richard H]

I've had some Ammonium Chloride kicking about for a long time, perhaps I should try it in some magnesium or mg/al stars and see how it compares to PVC and the other common chlorine donors.

[digger]

Yes, it's the molecular spectral emission of the excited metal chlorides. These tend to emit light in narrow bands of visible light and so give the best colours.

Yep thats the name for electron moving from a higher to a lower state

Edited by digger, 20 July 2007 - 04:45 PM.

[digger]

I've had some Ammonium Chloride kicking about for a long time, perhaps I should try it in some magnesium or mg/al stars and see how it compares to PVC and the other common chlorine donors.

That would be interesting, I wonder how much smoke they would give off. I tried a few ammonium chloride smokes at the weekend, they gave off an nice thick smoke screen with around 20 grams of comp (40% ammonium chloride).

Edited by digger, 20 July 2007 - 08:55 AM.