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Rainwater
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[*] posted on 3-1-2023 at 14:29


Quote: Originally posted by BerthelotOnCrack  
*zero* orange fumes,

If this was done in open air, I would test the reagents.
The less water the better, I use this procedure
https://youtu.be/ldPHzCnRYos
Only modification being in a cold water bath less than 10c, with almost anhydrous reagents.
Turns paper towels into a nice powder.

[Edited on 3-1-2023 by Rainwater]




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[*] posted on 18-3-2023 at 14:16


I can remember seeing something about an energetic powder made from k nitrate and k carbonate but that is ALL I remember. Anyone got any insight?



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[*] posted on 18-3-2023 at 16:37


Quote: Originally posted by arkoma  
I can remember seeing something about an energetic powder made from k nitrate and k carbonate but that is ALL I remember. Anyone got any insight?


There is an historical mixture called "yellow powder", allegedly percussion sensitive and possibly even a primary explosive in old descriptions.

It was made from a mixture of potassium nitrate, potassium carbonate and SULFUR in 3:2:1 ratio by weight.

The mixture had to be carefully and slowly heated to the melting point of at least one of the ingredients (sulfur being the most likely) with constant mixing, kept semi molten for a period, then allowed to harden and afterwards be crushed to a powder.

This mixture/product dearly loved to either catch fire or explode during processing. It was also hygroscopic.

There is at least one 1800's patent in USA for use as a percussion priming compound, I don't believe there was ever any substantial commercial use of this mixture/product. When I tried to replicate historical accounts of production, I had a few accidental fires and failed to produce a product which behaved as described more often than not. Then ONE TIME, IT WORKED. And damned if I could figure out what I'd done differently THAT time!

As always, if you are going to try? SMALL quantities and personal protective equipment are a must. I recall reading some descriptions by whoever took out the patent of pound sized batches going off in processing, how he lived long enough to get his patent is a good question.

There is speculation that the mixture + heating process generates polysulfides of unknown stoichiometry/behaviors. It definitely turned a darker orange/brown color during the heating & mixing process.

[Edited on 3-19-2023 by Bert]




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[*] posted on 19-3-2023 at 08:53


Thanks Bert. Believe I will leave this one alone.




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[*] posted on 3-4-2023 at 04:42


Hello everyone. Worldwide, it is not possible to determine the oxygen balance for sodium hypophosphite, NaH2PO2. Available but imprecise calculations point to -36.9 per CO2. But it is nonsense, because in molecule is not Carbon. Can any of you calculate it exactly?
Thank you. Dr. Liptakov....:cool:

[Edited on 3-4-2023 by Laboratory of Liptakov]




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[*] posted on 3-4-2023 at 11:18


LL, I’m guessing it’d just be substituting the complete oxidation of C to CO2 to P to H3PO4 (technically could be P2O5 but since H3PO4 is more stable it’s probably favored in the complete decomp pathway). Same as for assuming the OB% on NH4ClO4 (where I believe the Cl is oxidizing in its own right and converting to HCl). The general formula for OB% also takes into account metallic and non-metallic elements other than C, like Al and Fe2O3.
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[*] posted on 3-4-2023 at 14:05


Thanks, dettoo456....burning results show for NaH2PO2 x 1H2O on OB - 35. Is it not exact, but for orientation ratios is it useful.



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[*] posted on 12-4-2023 at 14:53


Does anyone happen to know about the acidic properties related to N-oxides (and also their acidity as it relates to N-oxides in hydroxy/ketone-containing heterocycles? For example, TKX-50 carries two NH2OH molecules as bases for the N-doxides on it and NTO exhibits mild acidity related to its amphoteric NHs at the 1 & 2 position(which tautomerize with the ketone to form OH- salts with metals and other bases). If one were to combine both a ketone and N-oxide into a single molecule though (like 5-hydroxytetrazole-2-oxide or even 3,6-dihydroxy-1,2,4,5-tetrazine-2,5-dioxide), how would it act as an acid? Would the base preferentially react with the N-oxide or the hydroxyl group, and would it be stabilized or sensitized by a constant ‘switching’ of metathesis neutralization at different positions?
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[*] posted on 14-4-2023 at 07:18


Yellow powder

Yellow Powder is a mixture of Potassium nitrate,Potassium carbonate and Sulfur. It has no apparent use in fireworks and should be made for educational reasons only.

Tutorial Take 20 parts of Potassium Carbonate and 10 parts of sulfur and melt it until a paste. Then let it solidify and add 30 parts of milled Potassium nitrate to the comp and mix it by diaper method. Besides the violent and unpredictable nature, the chronic hygroscopicity has the effect of making this substance unsuitable for firework manufacture.

Commonly found on less reputable internet websites and databases is a proposed method of manufacture involving three component melting. This method has been shown by experiments to very often detonate during this process. This is a good example of why, given the nature of explosives, one should be wary of trusting internet advice. Much of it is known to be false, and given the consequences of taking false advice. While the internet is an invaluable learning tool, Don't take what you read as true unless you have backed it up with a number of other sources, even though this will mean research will further delay your experimentation.

From Pyroguide

Would this work if you were to use sodium nitrate and sodium carbonate or Na Nitrate/ K Carbonate etc
Must it be KN and KC only?

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[*] posted on 14-4-2023 at 13:46


Mixtures Na / Na or K/Na or Na/ K will works. Only behavior will slightly different. Else melting point, else explo point. Else power of explo. Any way, using cold crushed Yellow powder has low practical using.




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[*] posted on 28-4-2023 at 16:46


(this is my first post :o but I have been a several years reader/member (not for "energetic materials" purpose :P))

I'm looking at different pest control (i.e. woodchucks in my case) smoke cartridges (M)SDS's and most of them have mostly the same formulation as black powder (nitrate, carbon/charcoal, sulfur) but with a ~1:1 nitrate/sulfur ratio instead of ~15:2 and containing about the same carbon/charcoal percentage.

Question: what is making black powder explode/deflagrate in a confined space (cartridge) but not those smoke cartridges, even though the nitrate oxidizer composition is only 1/3 less ?

[Edited on 29-4-2023 by proculation]
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[*] posted on 28-4-2023 at 16:52


Pressure, if you where to contain the smoke bomb in a pressure vessel, it would become a real bomb.
The composition amd processing are likely different
Commercial black powder is finely milled, sometimes for days to better mix the reagents and produce a faster boom.
As for pest control, you need a king snake.




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[*] posted on 29-4-2023 at 05:26


Guanidine perchlorate can be produced by double exchange reaction of guanidine hydrochloride with sodium perchlorate, possibly also ammonium perchlorate.
If I wanted to produce perchlorate of glycine, pyridine... would it be possible to produce these basic raw materials by reacting with HCl ? In an aqueous solution, or by introducing dried gas into the liquid.
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[*] posted on 29-4-2023 at 15:46


Quote: Originally posted by Rainwater  
Pressure, if you where to contain the smoke bomb in a pressure vessel, it would become a real bomb.
The composition amd processing are likely different
Commercial black powder is finely milled, sometimes for days to better mix the reagents and produce a faster boom.
As for pest control, you need a king snake.


Of course, I understand the pressure in an ammunition cartridge. My question was more about the difference in speed/velocity of the combustion/reaction between the two.

e.g. ignite a black powder (not necessarily commercial) filled cardboard cartridge like those smoke "bombs" and you would actually have created a "firework" and the whole thing would be propulsed out burning with the gas produced.

From what I understand, the concept of having about 1/3 less nitrate and more sulfur instead is to produce "incomplete" oxidation of the carbon/charcoal to create more CO than CO2 and also SO2 (CO and SO2 being the gases wanted to kill the pests). But why only that quite minimal change in composition can make such a big difference in the burning speed ?
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[*] posted on 29-4-2023 at 16:52


Its not clear what the complete composition is, but increasing the content of sulfer might also increases the SOx products. SO2 is toxic, SO3 would be cruel as it combines with water in the lungs to make H2SO4
I couldnt find and literature reguarding this exact topic
[Edit]
https://www.jes.or.jp/isem/2017/invitedspeakers/documents/Mi...
This paper list normal black powder's products of conbustion.
Its a mix of K2S, K2CO3 and K2SO4.
Given the excess of sulfer, K2S and K2SO4 should be major products
These will acidified water and is an inhalation hazard.
The particulate size is listed as 1uM. This also poses an inhalation hazard.

[Edited on 30-4-2023 by Rainwater]




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[*] posted on 11-5-2023 at 19:08
Low molecular weight exhaust/high combustion energy ramjet fuel?


I don't do much work with "exotic" or liquid rocket fuels. Looking at the recent trends in tactical rockets, a number of deployed systems are using fuel rich SOLID fueled rocket engines which once up to speed change from high thrust fuels to an insufficiently oxidized fuel and add rammed atmospheric oxygen to their incompletely burned rocket exhaust either in the primary combustion chamber or some arrangement of "afterburning" expansion bell.

Looking at several tables for LIQUID fuels offering low molecular weight combustion products/high combustion energies while considering potential fuel for a similar hybrid rocket/ram air breathing combustion system? I see lithium borohydride has 24.89g/100cc solubility in tetrahydrofuran @ 25°C. Density of such a solution is perhaps a bit low, molecular weight of exhaust gasses looks interestingly low, combustion energy with air is quite decent.

Anyone got experience with how unstable in storage/toxic/corrosive/generally nasty a solution of Lithium borohydride in terahydrofuran might be? I do understand that some organic reactions makes use of such solution.

https://en.m.wikipedia.org/wiki/Meteor_(missile)

https://en.m.wikipedia.org/wiki/Air-augmented_rocket#:~:text=Typical%20solid%20rockets%20have%20a,oxygen%20engines%20can't%20

https://www.sciencemadness.org/smwiki/index.php/Lithium_boro...

https://www.sciencemadness.org/smwiki/index.php/Tetrahydrofu...


[Edited on 5-12-2023 by Bert]




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[*] posted on 11-5-2023 at 20:44


Quote: Originally posted by proculation  
Quote: Originally posted by Rainwater  
Pressure, if you where to contain the smoke bomb in a pressure vessel, it would become a real bomb.
The composition amd processing are likely different
Commercial black powder is finely milled, sometimes for days to better mix the reagents and produce a faster boom.
As for pest control, you need a king snake.


Of course, I understand the pressure in an ammunition cartridge. My question was more about the difference in speed/velocity of the combustion/reaction between the two.

e.g. ignite a black powder (not necessarily commercial) filled cardboard cartridge like those smoke "bombs" and you would actually have created a "firework" and the whole thing would be propulsed out burning with the gas produced.

From what I understand, the concept of having about 1/3 less nitrate and more sulfur instead is to produce "incomplete" oxidation of the carbon/charcoal to create more CO than CO2 and also SO2 (CO and SO2 being the gases wanted to kill the pests). But why only that quite minimal change in composition can make such a big difference in the burning speed ?


Having used dozens of such pest control cartridges (rats! I HATE RATS) I observed the pressed composition was a very rough mixture, one could see crystals of the oxidizer on the pressed surface of the compressed composition without magnification. In a properly milled propellant powder, you would need a microscope to see the individual crystals of nitrate.

A similar sized pressed grain of powder in a small end burning rocket engine would burn for a few seconds. The "gopher gasser" cartridges smoldered for perhaps 30 seconds- A long, slow burn, skewed to produce excess sulfur dioxide and CARBON MONOXIDE. Very little chance for overpressuring a rat tunnel or otherwise going "kaboom".




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[*] posted on 12-5-2023 at 11:20


Quote: Originally posted by Bert  
I don't do much work with "exotic" or liquid rocket fuels. Looking at the recent trends in tactical rockets, a number of deployed systems are using fuel rich SOLID fueled rocket engines which once up to speed change from high thrust fuels to an insufficiently oxidized fuel and add rammed atmospheric oxygen to their incompletely burned rocket exhaust either in the primary combustion chamber or some arrangement of "afterburning" expansion bell.

Looking at several tables for LIQUID fuels offering low molecular weight combustion products/high combustion energies while considering potential fuel for a similar hybrid rocket/ram air breathing combustion system? I see lithium borohydride has 24.89g/100cc solubility in tetrahydrofuran @ 25°C. Density of such a solution is perhaps a bit low, molecular weight of exhaust gasses looks interestingly low, combustion energy with air is quite decent.

Anyone got experience with how unstable in storage/toxic/corrosive/generally nasty a solution of Lithium borohydride in terahydrofuran might be? I do understand that some organic reactions makes use of such solution.

https://en.m.wikipedia.org/wiki/Meteor_(missile)

https://en.m.wikipedia.org/wiki/Air-augmented_rocket#:~:text=Typical%20solid%20rockets%20have%20a,oxygen%20engines%20can't%20

https://www.sciencemadness.org/smwiki/index.php/Lithium_boro...

https://www.sciencemadness.org/smwiki/index.php/Tetrahydrofu...


[Edited on 5-12-2023 by Bert]


Damn it. That was one of my ideas, that I was going to develop, a fuel rich solid propellant capable of being a ramjet, it simplifies things greatly and I am upset they developed it before I could… I had formulations in mind as well. But I am sure the engineers in the 60s had thought of this too, they thought of everything. It’s painful to see an idea I was saving developed, but it also confirms my thinking is calibrated correctly.

Bert. I think solid fuels hold the candle here… liquid fuels do not have the density, yes, higher energy per unit volume…. But exotic liquid fuels will be around .6-1 density… I think solid can be up to 1.5 or high density… even 2.0 if done right!!

Lithium borohydride. Nice. Chem force has a video on excotic hydrides. Not sure if he tested LBH, but he did test borohydrides and mixed them with oxidizers. One showed the most impressive brisance I have ever seen… maybe above 10kms
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[*] posted on 12-5-2023 at 12:19


Quote:
Quote: Originally posted by MineMan  
.

Bert. I think solid fuels hold the candle here…


I was looking at a lower oxidizer % whistle mix with some azodicarbonamide added...




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[*] posted on 13-5-2023 at 23:48


Quote:
Quote: Originally posted by Bert  
Quote: Originally posted by MineMan  
.

Bert. I think solid fuels hold the candle here…


I was looking at a lower oxidizer % whistle mix with some azodicarbonamide added...


Have you used azidocarbonamide In pyrotechnics, it has an extremely high density and looks promising. Seems like it’s a “super fuel”. Isn’t density about 1.9?
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[*] posted on 14-5-2023 at 08:28


Quote:
Quote: Originally posted by MineMan  
Quote: Originally posted by Bert  
Quote: Originally posted by MineMan  
.

Bert. I think solid fuels hold the candle here…


I was looking at a lower oxidizer % whistle mix with some azodicarbonamide added...


Have you used azidocarbonamide In pyrotechnics, it has an extremely high density and looks promising. Seems like it’s a “super fuel”. Isn’t density about 1.9?


It's a gas generator when heated to fairly low temperatures. It is added in SMALL quantities as a fine powder to composite rocket fuels & propellants to increase burn speed, as each particle will blow up into a gas bubble/form a pit as it is heated either by conduction or IR below the burning surface, this effectively increases the burning area & speeds up deflagration of grains while providing some additional gas.




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[*] posted on 14-5-2023 at 16:26


What about in large quantities?
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[*] posted on 14-5-2023 at 20:08


Quote: Originally posted by MineMan  
What about in large quantities?


Azodicarbonamide has two possible decomposition scenarios depending on temperature. I am ASSUMING that when used in explosives/propellants rather than to puff up plastic resin or frozen pizza dough (YECH!!!) the decomoisition will be under the high temperature scenario, which decomposes it into carbon monoxide, nitrogen and amonia. Amonia and carbon monoxide DO burn, it's not going to be as high energy as many rocket fuels but COULD be used? All the use I've seen is as a small adjunct to modify burn speed in composite rocket fuels. Not sure how the economics work out, I suspect the energy per mass or volume are't attractive as a primary fuel when HTPB, PBAN and aluminum are available & cheap

Someplace around here is about 100g of it, it also speeds up slow burning star compositions, cheaper things did as well or better though.




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[*] posted on 15-5-2023 at 12:30


Quote:
thought the main attraction was a density of 1.9, if so it has far more energy per volume than other fuels… even close to Al



Could you give your source for density figure? The material I've handled is an extremely fine, low density powder. As it was manufactured/sold as a blowing agent for foamed plastics, the particle size was chosen for ease of wide dispersion in plastic resin feed stocks. It MAY have a high theoretical density/crystal density, the commercial product is less apparently dense than food grade corn starch, which it somewhat resembles.


[Edited on 5-16-2023 by Bert]

[Edited on 5-16-2023 by Bert]
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[*] posted on 10-7-2023 at 08:07
Dornier 335A's videos


I have found a dump of videos from Dornier 335A's channel on archive.org: here. While it's fortunate that they were saved, video descriptions are gone (as are comments). So when there're no details given in the video itself or file name, what was exactly tested (components, ratios and so on) remains a mystery.
So I have a question: have anybody here those descriptions saved in some form? Like screenshots, text dumps, memories, whatever.
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