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[*] posted on 5-12-2015 at 03:58


AN+Al would be better than flash powder to break rocks.
Most of flash powders are sensitive. detonator won't be needed.
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[*] posted on 5-12-2015 at 04:25


You're right, an ammonium nitrate-based explosive would be better to break up rocks.
If you only had flash powder and no access to high explosives, it would work, but would be inefficient as you would have to use a lot more and stem the boreholes etc.
But yeah, high explosives would be much better to use by a mile.




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[*] posted on 5-12-2015 at 10:31


One mole of H-C#C-H takes roughly 22.41 L and weights +/- 26g.
CaC2 + H2O --> CaO + H-C#C-H
CaC2 + 2 H2O --> Ca(OH)2 + H-C#C-H

Your silver acetylide nitrate double salt requires much less than 10g you need much less than 1 mole of CaC2/2,6...

----------------------------------------------------
Flash powder depending on its composition produces some gases; but if no gas is formed, then the gas trapped between the particles may expand violently owing to the heat of reaction...
Pirat bangers containing flash powder are void for 4/5; only 1/5 is the flash; the rest is air entrapped in a solid container.

----------------------------------------------------
2 KNO3 + 4 Al + S → K2S + N2 + 2 Al2O3
doesn't take in account the formation of SO2 gas!




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[*] posted on 5-12-2015 at 11:47


The flash powder mixtures with Sulfur or black Antimony sulfide do have both temporary and permanent gasses from their reactions. They are also more sensitive to work with- When young and foolish, some of us split up quite large, tough stumps with 50:25:25 Potassium chlorate:Antimony sulfide:American dark Aluminum powder. Wouldn't make that mix again...

Ammonium perchlorate:Magnesium flash has virtually all gasseous output, some temporary, some permanent. If you must try this, coat the Mg powder with dichromate using a Potassium dichromate solution and dry before mixing- And don't try to store it very long even then. See Shimizu FAST for details.

A (possibly safer) way to get some more gas output is to mix 50:50 flash powder:double based fast burning pistol or shotgun powder. Using equal weights of the standard 70:30 perchlorate:Al flash and a fast, high NG content pistol powder such as Alliant "Bullseye" produces quite a lot of gas & heat, hopefully without the added sensitivity of Sulfur or sulfides. I have NOT done formal drop hammer and friction testing on this mix, so please don't make any assumptions as to it being particularly safe to handle-




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[*] posted on 5-12-2015 at 18:45


Question regarding Silver acetylide, what is the difference between Silver acetylide double salt and just pure silver acetylide? As far as i know, it just require extra nitric acid for its production and has higher vod. Are there any differences in terms of, stability, power and such.
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[*] posted on 5-12-2015 at 21:23


Quote: Originally posted by Bert  
Google IS your friend...

Calcium carbide reaction with water:

CaC2 + 2 H2O → C2H2 + Ca(OH)2

So a 1:1 ratio of carbide to gas. But your starting material may not be very pure. Carbide lamp fuel pellets, "Big Bang" cannon ammo, etc. certainly are not.

Assume only 80% purity for such technical grade material, if freshly opened- Then do the stoichiometry. Need help with stoichiometry? We can move this to beginnings.


Well, I thank you for the help, and I'm sorry if my question was vague, but that isn't actually what I meant.

You see, you have to bubble the acetylene through the solution of silver nitrate and nitric acid. I don't quite know how much of the acetylene in these bubbles fully reacts before the bubbles escape form the solution. I don't think it all reacts does it? If that is the case, (and maybe I'm just really really showing my ignorance here), then don't I need a good excess of gas, and thus more calcium carbide than stoichiometric quantity?

None of the synths I have found specified an amount, mostly mentioning the amount of time they bubbled acetylene, such as "till it looked like there was no more precipitate forming" and "for about eight to ten minutes" and such. Such statements are rather unhelpful and seem to be unsound approximations.



[Edited on 6-12-2015 by KesterDraconis]
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smile.gif posted on 6-12-2015 at 08:59
Hydrazine Hydrate Ethanol azeotrope


Dose Hydrazine Hydrate form an azeotrope with Anhydrous Ethanol and if so what is the boiling point?



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[*] posted on 6-12-2015 at 12:20


While the dinitramide anion and its salts are well known, does anyone know of organic derivatives bearing that functional unit, i.e.

dinitramide derivatives.jpg - 4kB

Can primary amines be doubly nitrated under special conditions?

[Edited on 6-12-2015 by deltaH]




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[*] posted on 6-12-2015 at 22:36


Nevermind, I found my answer to my own question in the first-page preview of "An Overview on the Synthetic Routes and Properties of Ammonium Dinitramide (ADN) and other Dinitramide Salts" (requested).

Capture.JPG - 26kB




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[*] posted on 10-12-2015 at 10:24


Quote: Originally posted by ganger631  
Question regarding Silver acetylide, what is the difference between Silver acetylide double salt and just pure silver acetylide? As far as i know, it just require extra nitric acid for its production and has higher vod. Are there any differences in terms of, stability, power and such.

Silver acetylide Ag-C#C-Ag is formed from silver formate or acetate solution while bubbling acetylen through it.
As you can see it doesn't contain an oxydizer and so:
Ag-C#C-Ag --> 2 Ag + 2C
Only if air is present to some extend the following reaction occurs:
2C + 2 O2 --> 2 CO2

The double salt is Ag-C#C-Ag. x AgNO3. y HNO3 and it doesn't require nitric acid, only silver nitrate...
AgNO3 + H-C#C-H --> Ag-C#C-Ag. x AgNO3. y HNO3
As you can see there is nitrate oxydiser trapped inside the matrix. As such it produces of course more power and a higher VOD without need of external oxygen.

The basic salt (Ag-C#C-Ag) is said to be more sensitive vs the neutral (Ag-C#C-Ag.x AgNO3) and acidic (Ag-C#C-Ag. x AgNO3. y HNO3) ones.

For stability, as long as they are done correctly (demi water, demi water washed paper filter, no sunlight or strong light, clean chemically pure solvents, dried in the shadow at a moderate heat) and treated wel, they can store for years.




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[*] posted on 10-12-2015 at 10:37


Quote: Originally posted by KesterDraconis  
Quote: Originally posted by Bert  
Google IS your friend...

Calcium carbide reaction with water:

CaC2 + 2 H2O → C2H2 + Ca(OH)2

So a 1:1 ratio of carbide to gas. But your starting material may not be very pure. Carbide lamp fuel pellets, "Big Bang" cannon ammo, etc. certainly are not.

Assume only 80% purity for such technical grade material, if freshly opened- Then do the stoichiometry. Need help with stoichiometry? We can move this to beginnings.


Well, I thank you for the help, and I'm sorry if my question was vague, but that isn't actually what I meant.

You see, you have to bubble the acetylene through the solution of silver nitrate and nitric acid. I don't quite know how much of the acetylene in these bubbles fully reacts before the bubbles escape form the solution. I don't think it all reacts does it? If that is the case, (and maybe I'm just really really showing my ignorance here), then don't I need a good excess of gas, and thus more calcium carbide than stoichiometric quantity?

None of the synths I have found specified an amount, mostly mentioning the amount of time they bubbled acetylene, such as "till it looked like there was no more precipitate forming" and "for about eight to ten minutes" and such. Such statements are rather unhelpful and seem to be unsound approximations.



[Edited on 6-12-2015 by KesterDraconis]

Usually the expensive material is the AgNO3 and not the acetylen from CaC2...thus as such one usually exhaust the AgNO3 solution with an excess of acetylen by several filtrations, bubbling and demi water washings.

The white trouble is a clear evidence that some AgNO3 is stil present when bubbling acetylen through the solution...so filtration and washing then rebubbling, refiltration and rewashing is the best way to improve yield.

This explains why it seems so unclear...also if you have an excess of AgNO3 vs the acetylen, you may get the not suitable complex Ag-C#C-Ag. 6 AgNO3 (not detonable) so better use an excess of acetylen.

Finally the best design to use acetylen at best is long vertical reactor with a slow flow of acetylen from the bottom (long plastic tube to the bottom of a big vial for example); that way the gas has the time to dissolve a bit into the solution and to react with the AgNO3 all its way up to the surface.
Acetylen is moderately soluble into water and the solubility is reduced by solutants (dissolved salts, acids and bases) (see solubility of gases in water) and by heat.
--> Cold solution, avoid too much HNO3 (or avoid it at all), maybe add a little aceton (will boost up acetylen solubility).

[Edited on 10-12-2015 by PHILOU Zrealone]




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[*] posted on 10-12-2015 at 11:48


Quote: Originally posted by deltaH  
Nevermind, I found my answer to my own question in the first-page preview of "An Overview on the Synthetic Routes and Properties of Ammonium Dinitramide (ADN) and other Dinitramide Salts" (requested).

Organic dinitramides R-N(NO2)2 are relatively unstable.
You can check some related documents and infos in the chloronitramide (R-NCl-NO2) or ethylene dinitramide treads by Axt on this forum.

Beware that for EDNA (ethylene dinitramide) and MEDINA (methylene dinitramide) "dinitramide" refers to two nitramide groups -NH-NO2 and not to dinitramide -N(NO2)2...thus not to confuse with possible
-methylene bis-dinitramide (CH2(-N(NO2)2)2 = CH2N6O8)
-ethylene bis-dinitramide ((O2N)2N-CH2-CH2-N(NO2)2 = C2H4N6O8)

[Edited on 11-12-2015 by PHILOU Zrealone]




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[*] posted on 10-12-2015 at 12:24


Quote: Originally posted by PHILOU Zrealone  

Usually the expensive material is the AgNO3 and not the acetylen from CaC2...thus as such one usually exhaust the AgNO3 solution with an excess of acetylen by several filtrations, bubbling and demi water washings.

The white trouble is a clear evidence that some AgNO3 is stil present when bubbling acetylen through the solution...so filtration and washing then rebubbling, refiltration and rewashing is the best way to improve yield.

This explains why it seems so unclear...also if you have an excess of AgNO3 vs the acetylen, you may get the not suitable complex Ag-C#C-Ag. 6 AgNO3 (not detonable) so better use an excess of acetylen.

Finally the best design to use acetylen at best is long vertical reactor with a slow flow of acetylen from the bottom (long plastic tube to the bottom of a big vial for example); that way the gas has the time to dissolve a bit into the solution and to react with the AgNO3 all its way up to the surface.
Acetylen is moderately soluble into water and the solubility is reduced by solutants (dissolved salts, acids and bases) (see solubility of gases in water) and by heat.
--> Cold solution, avoid too much HNO3 (or avoid it at all), maybe add a little aceton (will boost up acetylen solubility).

[Edited on 10-12-2015 by PHILOU Zrealone]


Thanks, I suppose there really is no definite way to find smallest amount of acetylene necessary. Its ok for me though, I solved that problem yesterday by finding a cheaper source of carbide, so I don't have to worry about saving it/running out nearly as much.
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[*] posted on 11-12-2015 at 10:52


Quote: Originally posted by KesterDraconis  
Quote: Originally posted by PHILOU Zrealone  

Usually the expensive material is the AgNO3 and not the acetylen from CaC2...thus as such one usually exhaust the AgNO3 solution with an excess of acetylen by several filtrations, bubbling and demi water washings.

The white trouble is a clear evidence that some AgNO3 is stil present when bubbling acetylen through the solution...so filtration and washing then rebubbling, refiltration and rewashing is the best way to improve yield.

This explains why it seems so unclear...also if you have an excess of AgNO3 vs the acetylen, you may get the not suitable complex Ag-C#C-Ag. 6 AgNO3 (not detonable) so better use an excess of acetylen.

Finally the best design to use acetylen at best is long vertical reactor with a slow flow of acetylen from the bottom (long plastic tube to the bottom of a big vial for example); that way the gas has the time to dissolve a bit into the solution and to react with the AgNO3 all its way up to the surface.
Acetylen is moderately soluble into water and the solubility is reduced by solutants (dissolved salts, acids and bases) (see solubility of gases in water) and by heat.
--> Cold solution, avoid too much HNO3 (or avoid it at all), maybe add a little aceton (will boost up acetylen solubility).

[Edited on 10-12-2015 by PHILOU Zrealone]


Thanks, I suppose there really is no definite way to find smallest amount of acetylene necessary. Its ok for me though, I solved that problem yesterday by finding a cheaper source of carbide, so I don't have to worry about saving it/running out nearly as much.

There is, you simply need a closed reactor and a pressure gauge (manometer) or water displacement system and a recirculating device for the undissolved/unreacted acetylen...while it reacts the initial volume will be reduced and the gaseous volume above the liquid will shrink...then by trial error, you may find the minimal amount...




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[*] posted on 12-12-2015 at 10:08


Quote: Originally posted by PHILOU Zrealone  

There is, you simply need a closed reactor and a pressure gauge (manometer) or water displacement system and a recirculating device for the undissolved/unreacted acetylen...while it reacts the initial volume will be reduced and the gaseous volume above the liquid will shrink...then by trial error, you may find the minimal amount...


Hmm, you know that sounds like it would be quite a bit of work or money to either construct or buy such a device. At the same time it sounds like quite a bit of fun, and I think the information perhaps would be useful to people doing this synth in the future. I will consider it.
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[*] posted on 16-12-2015 at 10:00


Sorry for interrupting this discussion :)

Does someone have a paper about a one pot synthesis of carbohydrazide (diaminourea)

I already have a paper but with a two pot synthesis of carbohydrazide.
The problem is that it is designed for industrial use and not very commercial for me. :(
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[*] posted on 16-12-2015 at 12:14


Quote: Originally posted by Mr.Greeenix  
Sorry for interrupting this discussion :)

Does someone have a paper about a one pot synthesis of carbohydrazide (diaminourea)

I already have a paper but with a two pot synthesis of carbohydrazide.
The problem is that it is designed for industrial use and not very commercial for me. :(

No paper but in principle reacting urea with concentrated hydrazine will evolve gaseous NH3 and leave you with aminourea and diaminourea (DAU)...

You may also work with common chemistry...
Phosgene + hydrazine -->DAU
Dimethyl carbonate + hydrazine --> DAU
...

[Edited on 16-12-2015 by PHILOU Zrealone]




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[*] posted on 28-12-2015 at 16:59


I found a product in a store with 40% Ethylene glycol.
I am not sure about the rest 60% of the product. I am not sure if it is water or antirust material.
is it possible to get concentrated Ethylene glycol from this product. I was thinking about distillation but glycol has boiling point of 190 degrees and if I have water in the solution this won't work as I think.

any suggestion ?
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[*] posted on 29-12-2015 at 00:32


From what I have seen the anti corrosion additive is normally in very small quantity. It depends on what the climate is like where you are how much, and if, antifreeze needs to be used at all; in Las Vegas I read that anti corrosion chemicals are added to plain deionized water and that can be used as coolant, where I am it gets pretty cold so 50% ethylene glycol is normally used (considerably less concentration could normally be used, but 50% gives a good margin of safety for really low temperatures and possible reduction in ethylene glycol concentration over time, etc). I can get 50% concentration which is made to be poured right into the rad without dilution and basically 100% concentration which is meant to be diluted with distilled or deionized water.

It has been a few years since I have distilled any but from what I remember it is extremely easy to distill with very high purity, concentration and recovery with even a very simple pot still and condenser (one stage). The still needs to be able to handle 200C or more and ethylene glycol dissolves most normal rubbers and plastics from what I have seen (ruined a few items playing with it originally), but something all metal can be easily improvised. I have only ever distilled the undiluted antifreeze, but the 50% or 40% variety could be distilled too if none of the 100% stuff could be found. When distilling 1L or so of the "100%" variety I remember a couple millilitres or so of nearly pure water coming over at around 100C and then literally only a couple drops coming over as the temperature rose from 100C to about 190C. At around 190-200C or so a steady stream of practically pure ethylene glycol came over. I remember getting significantly better yields of EGDN using the distilled ethylene glycol than NG when using glycerine from the drug store using the same acids.


[Edited on 29-12-2015 by Hennig Brand]




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[*] posted on 29-12-2015 at 01:30


you can by almost pure ethylene glycol if you get concentrated coolant.



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[*] posted on 29-12-2015 at 03:54


@Hennig,
If 60% is distilled water , I think water will evaporate at 100C before Glycol. do I need to add H2SO4 to avoid water evaporation ?
I also can heat till 100 C till water get out then start to distill and collect the concentrated Glycol.

If 60% is antirust, what should I do now ? :)
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[*] posted on 29-12-2015 at 09:21


The coolant I had was a florescent green type color IIRC. I distilled to remove the tiny amount of water it contained but mostly to separate it from the dye and other higher boiling point materials. The distillate which came over at around 190-200C was crystal clear and basically anhydrous.

Ok, found some equilibrium data, there will be some losses especially when starting with coolant with a high concentration of water.

The equilibrium data came by way of the Wiki ethylene glycol data page. The data actually came from the following chemical engineering research database however.

http://www.cheric.org/research/kdb/hcvle/showvle.php?vleid=1...

I added a couple of columns and made the table into a pdf. Hope I didn't mess up the calculations, I feel rusty.


Attachment: Ethylene Glycol-Water Equilibrium Data.pdf (296kB)
This file has been downloaded 415 times



Here is an ethylene glycol data page as well.

Attachment: Ethylene Glycol Data Page.pdf (1.9MB)
This file has been downloaded 423 times


[Edited on 29-12-2015 by Hennig Brand]




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[*] posted on 29-12-2015 at 09:36


I preformed a similar distillation of the glycol from the dark green dye and was very pleased with the very small amount of water that had to be disrcarded. ~35ml
I just began collecting around 180C.
The type I used was given to my by elementcollector and came from a black jug. It was meant to be used as a an antifreeze for RVs IIRC.






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[*] posted on 29-12-2015 at 21:56


I have been told not to install an electrical outlet inside of my fume hood, I assume because of the risk of explosion. Is it really that unsafe? I hoped that by placing it near the sash I could minimise this chance greatly, it certainly seems safer than stringing cords around he outside...
Any input would be greatly appreciated.




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[*] posted on 30-12-2015 at 00:14


It depends on what you are doing in your fume hood, but NOT having any non explosion proof electricals inside your hood gives you greater flexibility in what you CAN do safely.

Electric sparks and flammable/explosive vapors and dusts are a bad mix, M'kay? I have heard first hand horror stories from people about using diethyl ether and throwing a standard wall light switch, just before they lost their lab. How they saw that little flame exit the switch plate, right before the open solvent filled container exploded.

Alternatively, you can obtain explosion proof electrical boxes, use heavy walled conduit and explosive atmosphere rated wiring devices and feeds. We have done this in one shipping warehouse/magazine that needs to be used any time of day, the equipment is VERY expensive.

We also have a small prefab building just for handling explosives in preparation and re-packing. There are no electrical circuits inside it- Exterior LED lights shining in through windows near the roof allow use after dark. All conduits, electrical boxes and switches are OUTSIDE the building. Cheapest reasonably safe solution.




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