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PHILOU Zrealone
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Quote: Originally posted by Paddywhacker | Mercuric oxide should be a vigorous oxidant in a thermite-type reaction. Only useful if you really wanted to contaminate a site, though.
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It will also get much more explosive power owing to the vapourisation of Hg into gas...also the combination of oxygen and Hg into HgO molecule is very
weak because a simple warming can free O2...so keep a safe distance from it, it must be handeled with due caution and only in tiny amount.
Initiation and power might be as fast and strong as flash powder!
[Edited on 31-3-2009 by PHILOU Zrealone]
[Edited on 31-3-2009 by PHILOU Zrealone]
PH Z (PHILOU Zrealone)
"Physic is all what never works; Chemistry is all what stinks and explodes!"-"Life that deadly disease, sexually transmitted."(W.Allen)
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grndpndr
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Quote: Originally posted by PHILOU Zrealone | To be honnest...think a bit to what will happen if you blast a thermite mix?
It will spray all arround and take the reactants away from each other fast before they have had the time to react!
Even a fast exploding thermite won't exceed 500m/s while any low detonation is over 1,5km/s so better use only the Al/Zn/Mg powder in the explosive
immediately because the other metal oxyde will be only dead weight-inert body!
PH Z
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In the military an expedient flame device is a modified incendiary grenade using det cord/det and a squib to ignite the flare comp/thermate/detonator-
det cord.The lethal/wounding radius
supposedly 35meters.Big difference between military thermate incediary device and a mechanically mixed thermite so FWIW fragmenting thermate devices
are possible rigged correctly.
TM 9-1330-200
[Edited on 30-6-2009 by grndpndr]
[Edited on 30-6-2009 by grndpndr]
[Edited on 30-6-2009 by grndpndr]
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ammonium isocyanate
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I plan on using a few exotic thermite comps for my little brother's birthday. Here are a few possibilities I'm considering:
Al + Fe2O3 + CuSO4 (for color)
" + " + LiCl
Al + Fe2O3 + (NH4)2Cr2O7 + maybe something for color
Mg + (C2F4)
I'll post the results if they're interesting.
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12AX7
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I doubt you'll get much color. Barium nitrate and magnalium (note: on topic: mixture is essentially a thermite intended specifically to yield barium oxide ) make an *almost* greenish burn, but it's much more overpoweringly white, from
sheer blackbody radiation. Some chlorine in the mix would probably help greenify it, though. Maybe the same can be applied to thermite, in which
case you'll need a chlorine source. The LiCl may work well for that reason.
Tim
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ammonium isocyanate
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My understanding was that chlorine deepens color. Is it specific to green? Becasue if so, the red/orange color of lithium flam would be
counterproductive.
I might have just regular thermite surrounded by little piles of metal + oxidizer + color donor.
Or give the magnesium + teflon one a try. It creates alot of soot, so its used by the military for arial smoke screens. Could be cool, because the
soot acts like a grey body. It might be hot enough to glow.
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chloric1
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No chlorine is not specific to green. When LiCl is dissolve in methanol or in a pyromix, the flame is decidingly crimson. It has more to with the
volatile species. Chlorides are more volatile than oxides and its these vapors that color the flames with excited states. All nitrates, carbonates,
and sulfates are oxide yielding so there affects on flame color are weak.
Fellow molecular manipulator
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ammonium isocyanate
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Well, I finally got around to testing the LiCl thermite idea.
It was a little windy, and my lighter didn't work to well. I didn't want to waste reagents, so I crushed and mixed the following: 6.46 grams of MnO2,
3.03g of Al, and 1.15g of LiCl. I then stuck a magnesium ribbon in and tried to light it. No go.
So I added a couple match heads next to it to give a nice little intense flame. The ribbon still wouldn't light.
So then I added a little aluminium/NaNO3 mix to the top (around a gram or two). Still didn't light.
And then I added some aluminium/sulfur mix to the top (again, around a gram or two) Still didn't light!!
So I poured about a gram of magnesium powder on top. Finally it lit!
For a moment, all I could see was the Mg burning. Then the lithium color started to appear. After about a second of that, all color was just drowned
out by an intense white light. So lithium chloride doesn't really have much affect, as it seems.
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PHILOU Zrealone
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LiCl is less good as LiOH...contrary to other salts where the chloride favors a rapid lower temperature ionisation of the cation, it is not Li(+) that
induces the red color, but it is the sublimated LiOH (thus the entire molecule that provides the color).
Also:
Too high temperature mixes provide a color shift to the white side!
Pyrotechnic is an art to make mixes with the best appropriate burning temperature to allow the best color expression...it has taken centuries of
research to achieve obscure mixes of given compositions...sometimes family secrets recipes
And to ammonium isocyanate:
NaNO3 will ruine the red color of LiOH...yellow Na(+) cation is the enemy of color for pyrotechnicians...better use a little KNO3...
[Edited on 26-7-2009 by PHILOU Zrealone]
PH Z (PHILOU Zrealone)
"Physic is all what never works; Chemistry is all what stinks and explodes!"-"Life that deadly disease, sexually transmitted."(W.Allen)
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12AX7
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FYI, a chloride added to thermite will melt and may shield the aluminum, requiring heavier ignition source. On the other hand, it will flux the
reactants somewhat, and volatize once burning.
Tim
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ammonium isocyanate
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Well in my quest to find a reliable ignition source in windy conditions I have stumbled upon a very interesting mixture. It turns put that ammonium
dichromate mixed thoroughly with magnesium powder provides an experemely bright flash when lit. It also covers anything within a foot with a layer of
MgO. Unfortunately, becasue the explosion is so fast, it does not light thermite.
Regretably I did not measure out the weights, so I'm not exactly sure what the stochiometry of the reaction looks like. However, I tried it using
aluminium powder (much cheaper), with 2.667 mols per mol (NH4)2Cr2O7 guessing at this stochiometry: 8Al + 3(NH4)2Cr2O7 -> 4Al2O3 + 3Cr2O3 + 2NH3 +
H2. However, nothing happened except some normal decomposition of the ammonium dichromate
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Ritter
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Noticed on eBay
A CD-ROM with over 725 patent pdfs covering both THERMITE & powdered metal+inorganic oxidizer applications:
eBay item #360228321223
Ritter
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\"The production of too many useful things results in too many useless people.\"
Karl Marx
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hissingnoise
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Ritter, try searching Google Patents for thermite mixtures or similar. . .
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Ritter
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Google Patents is very 'noisy' due to the OCR screening technology they used to convert the scanned patent documents into searchable data, which
resulted in a lot of patents of poor print quality getting garbled in translation. It is very incomplete as a result & many things get missed when
you search that database. It also covers only US patents. A lot of the early work by Goldschmidt & others were never patented in the US.
This CD has over 700 patents. Why reinvent the wheel?
[Edited on 22-1-2010 by Ritter]
Ritter
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\"The production of too many useful things results in too many useless people.\"
Karl Marx
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The WiZard is In
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chromium themit
Quote: Originally posted by PHILOU Zrealone | There was an extremely good post about thermites on alt.engr.explosive NG that was posted by Don Haarman 2 or 3 month ago!
You have a very long tale very instructive that explains all you want to know about all kinds of themites with various oxydes!
[snip]
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I /dh/would add this from Popular Science 1935, on chrome thermit. Viewable via Google.com/books.
http://tinyurl.com/yhbqogo
And the "Home Chemist" Popular Science, September 1941. I cannot find this issue at Google.com/books. |
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franklyn
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Can't think why The WiZard is In has posted this over there , if it properly belongs here.
http://www.sciencemadness.org/talk/viewthread.php?tid=13789
Survey of Combustible Metals, Thermites, and Intermetallics of Pyrotechnic Applications
- http://tinyurl.com/2f2bbj4
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The WiZard is In
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Ga Tech copper oxide thermite "explosion"
This I can believe.
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Ga. Tech Students Hurt in Explosion at Frat House
Officials: Students mixed chemicals, causing blast
Updated: Wednesday, 02 Jun 2010, 6:50 PM EDT
Published : Wednesday, 02 Jun 2010, 4:46 AM EDT
By DARRYL CARVER/MYFOXATLANTA STAFF/myfoxatlanta
ATLANTA, Ga. - Two Georgia Tech students are in critical condition after fire
officials say they mixed chemicals that exploded.
Atlanta fire officials tell FOX 5 they were called to the Zeta Beta Tau fraternity house
at around midnight after reports of an explosion. When firefighters arrived, they found
two Tech students, who they said had been mixing chemicals outside on a patio on the
back side of the house. Georgia Tech officials say Tommy Keen of Peachtree City, an
aerospace engineering sophomore, and Paul Grzybowski of Appling, a materials science
junior, had been mixing chemicals that caused the explosion.
Officials said the chemicals the students mixed were aluminum powder and copper [oxide, either /djh/]
powder, creating a thermite explosion. Fire officials say about 15 people who were inside the house
at the time of the incident, but they had already evacuated by the time emergency crews arrived.
Georgia Tech released a statement Wednesday, saying "The Institute's Environmental Health
and Safety team is working closely with the Atlanta Fire Department to determine the exact
nature of the materials involved in this incident and how the injuries occurred. Georgia Tech's
primary concern is focused on the condition and well-being of the students involved in this
incident....While the extent of their injuries is unknown at this time, Georgia Tech will continue
to closely monitor their conditions."
The victims were transported to Grady Hospital for treatment of burns to their face, chest and hands.
Fire officials say the explosion appears to be accidental.
The incident is under investigation by the Atlanta Fire Department, Homeland Security and
authorities with Georgia Tech.
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The original claim that they ignited their thermite with a butane tourch is not believable for
an iron oxide (any of the irons three oxides) thermite.
The dangers of fine copper oxide and aluminum powder are well know. Courser materials are
used to weld copper. Cadweld® being a commercial product.
The Cadweld MSDS's list both Cu2O and CuO.
http://www.erico.com/public/library/MSDS/LT1273.pdf
https://www.erico.com/public/library/MSDS/LT1298.pdf
Starting material — [I have seen a sparkler used.]
http://www.endeavorelectric.com/msds/MSDS-Cadweld%20Cadstart...
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Mildronate
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Here you can see may experiments with CuO + Al
http://www.youtube.com/watch?v=x6BjCxMVwUE
http://www.youtube.com/watch?v=kynAI0F8bfI
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the Z man
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I tried Mg fillings + PbO2 in a tiny quantity for fun. Not sure about the ratio, maybe 2 parts Mg + 1 part PbO2 by volume. It deflagrates in a very
similar way to KNO3/Mg flash, maybe a little more violently, leaving a dark halo. No Pb found, probably vapourized.
I found a mix of PbO2/Mg/S/KNO3 (ratio something like 1/3/2/2 by volume) to deflagrate very violently, about one quarter gram going THUMP.
I'm thinking about copper peroxide. I found very little on this compound although it seem to exist, in strange compexes like CuO2*H2O2 ( http://www.springerlink.com/content/w675741vu4156421/). Maybe CuSO4+bleach or NaOH+H2O2? Seems too simple.
Now a strange thing maybe a little OT. When I used to play with KCLO3/Cu powder/S mixture (suicidal I know...) I mixed the copper powder ad sulfur
first. Once I was mixing them very fast in a plastic beaker using a glass rod, when it caught fire! It was strange, it caught fire suddenly but not
like a deflagration, it was like all the sulfer caught fire all at once not violently. It's weird that a Cu/S mix is friction sensitive, isn't it?
[Edited on 18-6-2010 by the Z man]
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Anders Hoveland
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I have tried magnesium powder with sulfur, and Mg powder with MnO2.
Adding sulfur to thermite seems to make it ignite a little easier, and increases the initial burn rate, but the smoke is very offensive in large
quantities. The Mg with MnO2 made mushroom clouds that went up 20ft, even when only a few grams of thermite were used. The Mg thermite burns very
fast, almost explosively, and there is a blinding white flash, even very bright in the daytime, but in daytime the torrents of smoke are even more
visible.
[Edited on 20-6-2010 by Anders Hoveland]
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Anders Hoveland
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I had a thought to use CuMnO4 (cupric manganate) as the oxidizer with magnesium or magnalium (Mg-Al alloy common in pyrotechnics) powder. Mg-Al would
actually be more explosive because, due to Mg reactivity, there is an effective limit to how fine of a powder is available. Smaller powder size is
somewhat important, as if one uses bits of aluminum foil put through a cheese grater(not finely ground), it will not work for thermite.
CuMnO4 + 3Mg --> 3MgO + MnO + Cu
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argyrium
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O/T - but..
Quote: Originally posted by the Z man | SNIP...
Now a strange thing maybe a little OT. When I used to play with KCLO3/Cu powder/S mixture (suicidal I know...) I mixed the copper powder ad sulfur
first. Once I was mixing them very fast in a plastic beaker using a glass rod, when it caught fire! It was strange, it caught fire suddenly but not
like a deflagration, it was like all the sulfer caught fire all at once not violently. It's weird that a Cu/S mix is friction sensitive, isn't it?
[Edited on 18-6-2010 by the Z man] |
Movement of the S in the plastic container very possibly generated enough static to ignite the suspended particles; probably not friction.
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Microtek
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Quote: |
Smaller powder size is somewhat important, as if one uses bits of aluminum foil put through a cheese grater(not finely ground), it will not work for
thermite.
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Thermite works fine with very large grain sizes, it's just hard to ignite and burns slowly. For many applications this is preferable. I have made
excellent thermite using un-shredded (ie. whole) aluminum foil, but it required a small regular thermite charge to ignite it.
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Anders Hoveland
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I wonder if adding some NaOH to thermite would boil elemental sodium off in the absence of air.
3NaOH 4Al Fe2O3 --> 3Na 1.5 H2 2Al2O3 2Fe
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Skyjumper
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Quote: Originally posted by the Z man | I tried Mg fillings + PbO2 in a tiny quantity for fun. Not sure about the ratio, maybe 2 parts Mg + 1 part PbO2 by volume. It deflagrates in a very
similar way to KNO3/Mg flash, maybe a little more violently, leaving a dark halo. No Pb found, probably vapourized.
I found a mix of PbO2/Mg/S/KNO3 (ratio something like 1/3/2/2 by volume) to deflagrate very violently, about one quarter gram going THUMP.
I'm thinking about copper peroxide. I found very little on this compound although it seem to exist, in strange compexes like CuO2*H2O2 ( http://www.springerlink.com/content/w675741vu4156421/). Maybe CuSO4+bleach or NaOH+H2O2? Seems too simple.
Now a strange thing maybe a little OT. When I used to play with KCLO3/Cu powder/S mixture (suicidal I know...) I mixed the copper powder ad sulfur
first. Once I was mixing them very fast in a plastic beaker using a glass rod, when it caught fire! It was strange, it caught fire suddenly but not
like a deflagration, it was like all the sulfer caught fire all at once not violently. It's weird that a Cu/S mix is friction sensitive, isn't it?
[Edited on 18-6-2010 by the Z man] |
I hope you did that in a hood. Lead vapor/ compounds in the air are not good for you. At all. I highly doubt Cu/S is friction sensitive, or at least
that friction sensitive. Your plastic probably was not clean.
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Anders Hoveland
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I tried magnesium powder and epsom salt (MgSO4.7H2O). I tried in all different proportions. One would think this would be a violently reactive mix
because burning magnesium explodes if water is added to it, but I failed to get this mixture to ignite and burn. I even put a mix of Mg and KClO4
above it and ignited it, but this still did not cause the bottom layer to burn. I think perhaps the hydrate absorbs much heat in giving off its water.
Perhaps using Ag2O2, which is not the peroxide, but the I,III oxide of silver, which is made from silver salts and H2O2 I think, it is on wikipedia.
There is always Au2(MnO4)3 which can be made if you have the money to throw around. The synthesis involves gold, Cl2O7 and MnO2.
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