40 replies to this topic

[Potassium chlorate]

i think i remember reading it was used in warheads on torpedo's and artillery shells. its impact sensitive. what use did it have in fireworks?

It was very common in WWI, since TNT was more expensive and harder to produce.

It was a very powerful oxidizer in fireworks. The salts of it were also used, like potassium picrate in whistles.

[CCH Concepts]

i would love to see this stuff in action. i brought some aquas picric acid from ebay, when i first started on pyro. but then the more i read, i realized it wouldn't do anything as it was and even if i did play with it to make it useful i was sure if i wanted to, being everything i read sounded like i was risking getting myself in trouble or hurt.

[a_bab]

Your yellow solution of picric acid won't do many things: saturated it only contains like 16 grams/liter (if my brain is not farting right now).
Besides, it is really toxic and bitter. It is a wonderful wool pigment too; the "canary yellow" given by it is incredible.
Now back on topic please

From what I have learned so far:
- the electrolysis is no good; the output is low. A high current is needed. Special electrodes are needed (graphite works). Separating the very soluble barium chlorate from the less soluble barium chloride may be a chalenge
- I was fiddling with the idea of reacting sodium chlorate with barium chloride. This is the "standard" method found in the chemistry manuals.. But, the pesky sodium ions will get into the precious BC. Moreover, the resulted table salt solubility is really odd: at 0 degrees C the water dissolves something like 350 grams/liter; at 100 degrees something like 390 grams. So even cooling the solution won't precipitate too musch of the sodium chloride.
- the best method seems the one where ammonium chlorate (boooo!!!!) is reacted with barium carbonate/hydroxide.
In solution of course; the beast (ammonium chlorate) shall be well pacified.

[Arthur Brown]

Picrate whistles were dropped 50 years ago because the had a tendency to detonate and destroy things. They were replaced by gallate compounds then by Benzoate compounds. There really is NO need to go back to formulae that were proved to dangerous to use before the HSWA!

[drtoivowillmann]

Dear Pyro Friends:


There is an alterative system without BC, the colour of which is equally good. Might be a little bit expensive for amateurs:

Barium Nitrate
Magnalium (ratio 2 : 1),

add some mixture of Potassium Perclorate and Red Gum (ratio 4 : 1) or phenolic resin instead of it (ratio 5 : 1)
this ensures inflammation of Magnalium,

add about 3 % Hexamethylene Tetrammine,
deepens colour very well,

add about 0,5 % finest Copper Powder or Black Copper Oxide
as burning catalyst.


Greetings from Brazil:

Toivo

[drtoivowillmann]

There is an alterative system without BC, the colour of which is equally good. Might be a little bit expensive for amateurs:

Barium Nitrate
Magnalium (ratio 2 : 1),



Dear Friends:

I beg your pardon. There is a bigf mistake in my text: I omitted PVC.

So Barium Nitrate : Magnalium : PVC : Potassium Perchlorate (to oxidize PVC)
= 2 : 1 (up to 1.2) : 0,5 : 0.9 .

It's correct like this !


Thanks:

Toivo

[a_bab]

This is an interesting formula: high magnnalium content for a very hot flame.

Hexamine does not deepen the colors but rather makes the flame larger, so on the sky it apears brighter.


Toivo, can you share a good blue?

[Potassium chlorate]

I'd still prefer barium chlorate if you have any chance of getting hold of it. With parlon as a binder and additional chlorine donor you can even combine Ba(ClO₃)₂ and Mg(Al).

Any composition with KClO₃ or NH₄ClO₄ as an oxidizer will give an acceptable blue no matter the copper compound used. It's very hard to get a really deep blue, though.

Edited by Pyroswede, 19 December 2009 - 08:11 AM.

[MDH]

Use a low temperature fuel. Use metallic salts or fuels with a high copper content. Add compounds which neutralize white light emitters.

Creating a strong blue is actually quite simple once you know which factors contribute to the production of blue, and which ones prevent that blue from being seen.

[a_bab]

I know enough about blues; it's just I wanted to see a formula from Brasil.

For this NYE I'll test a whole bunch of blues, and I'll share the results with you. FYI, I've got on my list stuff like copper perc and such odities.

[a_bab]

I know enough about blues; it's just I wanted to see a formula from Brasil.

For this NYE I'll test a whole bunch of blues, and I'll share the results with you. FYI, I've got on my list stuff like copper perc and such odities.

[drtoivowillmann]

Dear Friends:

about blues I'll talk later.

About my green: don't be angry, but you did not understand anything.

# good green flames are spoilt by the formation of BaOH-radicals (yellow light) and BaO-molecules (orange light).
# to avoid reduce ALL Barium Nitrate do the pure Barium-element, by sufficient Magnalium. So the large amount
of Magnalium is not for brillancy but to clean the flame colour. The pure Barium is readily consumed by the
chlorine of PVC and some Potassium Chloride (reduction of the perchlorate), forming pure BaCl-radicals
(pure green light).
# There is still some soure of O and OH, in the form of H2O, CO2 and CO, from the burning of PVC, resin and
Arabic Gum that might spoil again our green. But at very high temperatures Hexamethylene Tetrammine
decomposes to Nitrogen and Carbene (H2C|), a very, very unstable particle with only 6 electrons linked to the
cabonic atom and an extreme powerful reduction agent., which clears the green again.

This is some Hi-Tec-chemistry for coloured flames (atention: Hexamethylene Tetrammine is too powerful with
blues = copper, they become all off-white), but ist works quite well.

Yours truely:

Toivo

[drtoivowillmann]

Dear Friends:

In order not to be lynched by you, because of my criticism, here my Brazilian Blue:

organic:

64 % Potassium Perchlorate
14 % PVC
10 % Black Copper Oxide
8 % Phenole Formaldehyde Resin
4 % Arabic Gum

Magnalium Version;

62 % Potassium Perchlorate
14 % PVC
10 % Black Copper Oxide
6 % Phenole Formaldehye Resin
4 % Magnalium
4 % Arabic Gum

# CuO is quite expensive, so I never use more than 10 %.
# Phenolic Resin is burnt to CO2 and water, the other compounds to CO and water, this is important.
# the ratio between Cu and Cl added (in the form of PVC) is always 1 : 1,8 , also important.

Greetings from Brazil:

Toivo

[MDH]

Dear Friends:

about blues I'll talk later.

About my green: don't be angry, but you did not understand anything.

# good green flames are spoilt by the formation of BaOH-radicals (yellow light) and BaO-molecules (orange light).
# to avoid reduce ALL Barium Nitrate do the pure Barium-element, by sufficient Magnalium. So the large amount
of Magnalium is not for brillancy but to clean the flame colour. The pure Barium is readily consumed by the
chlorine of PVC and some Potassium Chloride (reduction of the perchlorate), forming pure BaCl-radicals
(pure green light).
# There is still some soure of O and OH, in the form of H2O, CO2 and CO, from the burning of PVC, resin and
Arabic Gum that might spoil again our green. But at very high temperatures Hexamethylene Tetrammine
decomposes to Nitrogen and Carbene (H2C|), a very, very unstable particle with only 6 electrons linked to the
cabonic atom and an extreme powerful reduction agent., which clears the green again.

This is some Hi-Tec-chemistry for coloured flames (atention: Hexamethylene Tetrammine is too powerful with
blues = copper, they become all off-white), but ist works quite well.

Yours truely:

Toivo

Hello Dr. Toivo,

You are not going to be lynched for criticizing anybody, though I believe most of us here understand the basics of how green flames are produced. However, sensetivity aside, would sulfur not make a more simple and practical reducing agent if barium chlorate is not being used? Do you think that perhaps adding an additional coarser grade of magnesium would fix the problem of overoxidation? Perhaps a composition consisting only of Barium Nitrate, magnesium and dechlorane (no oxygen, just carbon and chlorine) in the right perportions would be better than the one being used now?

[drtoivowillmann]

Hello Dr. Toivo,

You are not going to be lynched for criticizing anybody, though I believe most of us here understand the basics of how green flames are produced. However, sensetivity aside, would sulfur not make a more simple and practical reducing agent if barium chlorate is not being used? Do you think that perhaps adding an additional coarser grade of magnesium would fix the problem of overoxidation? Perhaps a composition consisting only of Barium Nitrate, magnesium and dechlorane (no oxygen, just carbon and chlorine) in the right perportions would be better than the one being used now?

Dear Friend:

with the exception of strobes I do not think that the combination of Magnesium and Sulphur is a good idea.
Even in your system you should put in so much magnesium (to capture all oxigen), that its amount and the
resulting flame temperature would be very high. At so high temperatures BaCl will be decomposed thermically,
which weakens the flame colour. The escape is to make half the composition organic (what I did) to lower flame tewmpertature.
Try my compo as cut, pumped or rolled star, it remembers Barium Chlorate.

Greetings from Brazil:

Toivo