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View Full Version : Smoke compounds in the military.


simply RED
February 15th, 2004, 03:54 PM
I know these smoke compounds have been used by the military:

TiCl4 - reacts with mositure to produce Ti(OH)4 which is the smoke.
Red phosphorous - dispersed by TNT produces very rapidly thick white screens.
Hexachloroethylene - mixed with Zn powder and Zn oxide burns to produce ZnCl2. (white).

There must be other compound(s) in the army now because not a real smoke device i've seen here is armed with one of these. Do you know which compound i'm missing?
The last one militray smoke (white) i tried was unbelievably more powerful than any device i've made and smelled like burned paint.
(a freind of mine was talking about yellow compound that smells like mushrooms or gasoline, is such?)

Lil_Guppy
February 16th, 2004, 10:14 AM
Teraphthalic acid is used in the AN-M83 HC white smoke hand grenade. Have not experimented with it since I have not been bothered finding a supplier :P

simply RED
February 16th, 2004, 11:51 AM
May you give the whole composition.

Lil_Guppy
February 16th, 2004, 10:10 PM
You should be able to find a composition on Google. Skylighter sells the chemical, so they may have a composition in one of their articles.

simply RED
February 17th, 2004, 07:26 AM
There is nowhere the exact mixture used in the granade. Ter. acid (1,4 - benzodicarboxylic) does not produce smoke on its own.

Lil_Guppy
February 18th, 2004, 12:38 AM
Try asking on rec.pyrotechnics. There are probably many mixes for smoke using the ter acid.

Guerilla
February 18th, 2004, 05:59 AM
There are also HC based formulas that contain some calcium silicide, forming silicon tetrachloride which further reacts with moisture in the air creating the actual smoke compound, silicic acid. It seems there are only few non-HC based military smokecomps apart from those containing phosporous..

Im not sure if its only due to my hexachloroethane containing a bit of naphtalene (moth balls), but my HC/Zinc produces grey smoke. 10g of the comp:

hpy2bhre
February 26th, 2004, 12:24 AM
My hc mix comes out grey too! I'm using 90 hexachloroethane , 45 zinc oxide, 45 powdered zinc, and 7 to 10 powdered aluminium .`Its hard to start but once lit produces lots of grey smoke.I'll post as i experiment.

simply RED
February 26th, 2004, 10:05 AM
C2Cl6 + 3Zn = 3ZnCl2 + 2C
ZnCl2 + 1/2O2 ->< - ZnO + Cl2
C + O2 ==>(partial) CO + CO2 + C
The carbon may cause the grey smoke.

hpy2bhre
March 4th, 2004, 09:34 AM
I asked a friend in the know and was told that maybe the carbon is the cause and that at the temps of this burning composition the carbon should be combining with o2 from the air and forming co2 but if my smoke composition was burning to fast or if my vent holes were to big the reaction wouldn't have time to take place and the smoke would be blacker than normal. I will press another smoke stick today and use smaller vent holes to test this out. Anybody else have any thoughts on this?

Guerilla
March 5th, 2004, 03:04 PM
Adding some oxidizer like KNO3 to the comp would most likely consume the carbon and bleach the color somewhat..I guess making a smaller nozzle wont help alone as it will only cool the smoke and carbon particles more effectively, not making the carbon to combine with atmospheric oxygen very well.

simply RED
March 5th, 2004, 04:23 PM
Ethene tetrachloride (Cl2C=CCl2) may be used instead of C2Cl6, since C2Cl4 is more easily available. I have not tried it, but it is obvious. Ethene tet is liquid. Some ZnO and KNO3 may be added to slow down the reaction rate if required.

hpy2bhre
March 7th, 2004, 11:44 PM
I regrouped and think now that my black smoke is coming from the cardboard container burning. The only reason I think this is that today I pressed the comp into a 1 inch pellet with no container and the smoke, although a bit thinner than normal ( due to flaming?) was white. I have also tested and had better luck and easier starting with the formula:
50 parts Hexachloroethane
28 parts fine zinc powder
22 parts zinc oxide
I'll be using this formula for all my new test. It lights easy and puts out a great heavy, white smoke. I pressed it hard with a dowel with out hammering. Just as hard as I could press it with my body weight. My case is a thin tube 1 1/2 inch by 3 inch with a plaster of paris nozzle with a 1/4 inch drilled hole. I didn't time it, but it smoked for at least 2 min steady. The smoke looked like heavy fog and covered about an acre.

freaky_frank
March 23rd, 2004, 01:16 PM
What is the OTC source for hexachloroethane?

Cyclonite
March 23rd, 2004, 01:54 PM
There are also HC based formulas that contain some calcium silicide, forming silicon tetrachloride which further reacts with moisture in the air creating the actual smoke compound, silicic acid. It seems there are only few non-HC based military smokecomps apart from those containing phosporous..

Im not sure if its only due to my hexachloroethane containing a bit of naphtalene (moth balls), but my HC/Zinc produces grey smoke. 10g of the comp:

The military does use quite alot of non-HC based smokes, they moved away from HC due to the hazards.....Most of the colored smokes don't use HC

Guerilla
March 23rd, 2004, 03:17 PM
Okay, thanks for the correction. Do you mean HC is just being replaced with titanium/silicon tetrachloride or a similar chlorine donor, or are they getting rid of zinc chloride smokes in general? and yeah I was referring to the obscuring smokes only, I've got no idea what they use as an oxidizer in those colored smokes..a fairly low combustion temperature is needed anyway.

The_Rsert
November 26th, 2004, 06:42 PM
When you will mix an oxidiser (KClO3) with red phosphorous,
the red phosphorous will be oxidised to phosphorous pentoxide.
The phosphorous pentoxide is extremly hygroscopic and will form a thick fog in contact with air. :D