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Rosco Bodine
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[*] posted on 17-1-2018 at 13:58


@nitro-genes

Copper picrate has some odd properties and reportedly can decompose in boiling to produce some ammonia and the color of the red orange crystals you show pictured is like ammonium picramate. So there are several possible things going on there. Among the divalent metal salts that could be catalytic in reducing a picrate to picramate iron and copper are both reported. What combinations with ascorbic would work best is unknown, and likewise what proportions and conditions are best is unknown. A set of experiments could be formulated to identify the best process chemistry particulars and optimize the synthesis.

When the synthesis of picramic acid was being first contemplated, ascorbic acid and fructose were both promising reducing agents, also metallic iron and zinc. The observation about Zinin reductions using sulfides requires an alkaline reduction system where the picrate salt is what is being reduced, rather than free picric acid itself being reduced, is a general rule that I think will probably hold true for other reducing agents like ascorbate or fructose or glucose, or the lower oxidation state divalent metal salts as catalysts or reagents.

[Edited on 1/17/2018 by Rosco Bodine]
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aga
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[*] posted on 17-1-2018 at 15:10


Where would one start with sub-gramme quantities of an EM ?

I've read about many, yet am scared of the whole idea to be honest, so intend to make a remotely controlled micro-lab to at least try, certainly without having any part of me close enough by to be damaged in case it goes wrong.

A big issue (in my mind at least) is how to dispose of the results of Failed experiments.

As it would be sub-gramme, would simply burning the waste ensure that it was not dangerous ?




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nitro-genes
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[*] posted on 17-1-2018 at 16:19


@aga, You known once you go to the dark side, there is no turning back eh :D The danger involved when working with EM's depends on the specific EM. When working from pre-existing and thoroughly tested syntheses, relatively insensitive EM's, small quantities and with adequate precautions, the danger involved can be largely limited. Starting with picrates might be an idea, they are relatively benign (most biochemistry labs store it as a dye for tissue staining), easy to make, stable in storage and has an interesting chemistry.

@Rosco, there is a lot going on, pH and temperature probably being crucial factors. I haven't been able to produce the pure picramic again (or maybe it was a dinitro nitrosophenol?)...:( This may be far more difficult than I previously thought, and the reactions and precipitates involved seem really puzzling.

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Rosco Bodine
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[*] posted on 17-1-2018 at 23:01


Quote: Originally posted by nitro-genes  
Ok, so I made the orange-peel-insoluble-in-water-stuff again, trying to determine better the conditions for it's formation.

0.25 grams (~1 mmole) of picric were added to a 25 ml beaker, together with 0.27 grams of copper(II)sulfate pentahydrate (~1 mmole) and heated in 20 ml of distilled water to near boiling, upon which everything dissolved. NaOH solution was added to a pH of 7 to neutralize the picric. Then I weighed out 0.6 grams (~3.2 mmoles) of ascorbic acid and slowly started adding this to the picric/copper sulfate solution. When about 0.27 g was added (1.5 mmoles), a greenish-yellow precipitate started to form abundantly, the pH at this point was about 3-4. This was filtered off and washed thoroughly. The precipitate was resuspended in 10 ml of water and NaOH solution was again added at room temperature (pH of 10-12 or so), upon which it turned to a deep red-orange suspension. Upon acidifying again (this time using dilute HCl, instead of nitric) the bright orange precipitate formed slowly.

So no reduction to picramic, which would have required at least 6 electrons and 3 mmoles of ascorbic (3.5 if you don't count the copper reduction), though IIRC it's also only able to reduce nitro groups under more basic conditions. Curious what this stuff is exactly though. :)

[Edited on 16-1-2018 by nitro-genes]


Try these adjusted proportions for the reduction

Solution A

10 mmole picric acid
5 mmole copper sulfate
10 mmole NaOH

Use sufficient H2O to dissolve at 85C

Solution B

75 mmole NaOH + 63 mmole ascorbic acid

Use sufficient H2O to dissolve at 85C

These proportions should be close to theory

http://www.sciencemadness.org/talk/viewthread.php?tid=433&go...

[Edited on 1/18/2018 by Rosco Bodine]
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nitro-genes
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[*] posted on 18-1-2018 at 06:08


Why do you assume 6.3 mmoles of ascorbic, instead of half, so 3.15? Sorry if I'm getting this wrong, each mole of ascorbic would be able to donate 2 electrons to form dehydroascorbic right? And if IIRC, reduction of 1 nitro group, 6 electrons would be needed, so 3 moles of ascorbic per mole of picric (unless maybe a pH of >11 (kPa2 of ascorbic) is needed to donate 2 electrons. Another problem that I see is that solution B will have a very high pH, this will precipitate part of the copper as the hydroxide an when reduced by the ascorbic it will result in the insoluble orange-red copper(I) oxide.

[Edited on 18-1-2018 by nitro-genes]
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Rosco Bodine
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[*] posted on 18-1-2018 at 10:26


I think you may be seeing one of the hydrogens of ascorbic acid as a reducing hydrogen that is actually another different hydrogen "acidic hydrogen" that is tied up in sodium ascorbate.

The copper oxide was expected to be the insoluble end result byproduct that could be filtered from the hot sodium picramate solution. Likewise is iron oxide and manganese oxide ect for the other metal salts used. For the ascorbate reduction that was from earlier research that has not been reviewed again to confirm but there were some literature references checked. You could be right and it would require experiment to confirm. The slight excess ascorbate was provided for offset to air oxidation loss. Likewise the excess NaOH base was to make certain the reduction reaction system is progressing and increasingly basic.

Reviewed the literature and saw the 3 to 1 ascorbate experiments reported lower yields than expected. A color density development in a dilute sample experiment reaction system should confirm the quantity of ascorbate required, and likewise for reduction using fructose or glucose, because the sodium picramate product is such an intense dye that the reaction system functions as its own color indicating analytical test.

[Edited on 1/18/2018 by Rosco Bodine]
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[*] posted on 18-1-2018 at 11:53


As for even dipping a toe into the 'Dark Side' i'd clearly be on my own, and at risk :

https://www.sltrib.com/news/2018/01/18/utah-man-who-runs-pop...

Hardly seems that the risk will ever be worth the reward.




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[*] posted on 18-1-2018 at 12:39


Quote: Originally posted by aga  
As for even dipping a toe into the 'Dark Side' i'd clearly be on my own, and at risk :

https://www.sltrib.com/news/2018/01/18/utah-man-who-runs-pop...

Hardly seems that the risk will ever be worth the reward.

I thought that possessing explosives and synthesizing them was legal in the US, with an exception of Acetone Peroxide and some other that I don't remember.




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[*] posted on 18-1-2018 at 12:46


What is the best primary? I know, ambiguous question.
I want a low friction sensitivity but it still needs to make DDT reliably when confined and lit with an open flame coming from a fuse, and it also needs to be storable, it can't decompose with time.
SA(DS) was my first choice, but DDNP also drawed my attention.




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[*] posted on 18-1-2018 at 16:17


Quote: Originally posted by joseph6355  
Quote: Originally posted by aga  
As for even dipping a toe into the 'Dark Side' i'd clearly be on my own, and at risk :

https://www.sltrib.com/news/2018/01/18/utah-man-who-runs-pop...

Hardly seems that the risk will ever be worth the reward.

I thought that possessing explosives and synthesizing them was legal in the US, with an exception of Acetone Peroxide and some other that I don't remember.


In USA, under FEDERAL explosives laws, you can make explosives without a license. But you can NOT store them, use them in any commercial activity, move them on public roads, sell them or even give them away.

There is a culture of fireworks enthusiasts who have figured out how to work around the no storage/transport rules. They start with legal OTC ingredients and can make quite large, complex display fireworks shells in a single long work day. Sacks of chemicals, bottles of 2 part curing rubber/epoxy/polyester or whatever, plastic cans or hemispheres, string, paper, tape, hot melt glue. Some of them even look pretty good in the sky.

Classes are taught in these techniques at PGI conventions, the Western Winter Blast, etc.

https://www.pgi.org/convention/2018/

https://www.westernpyro.org/events


So if you can make it in a day, or better yet, on site- Yes, you are probably good with BATF. But each state and even county, city or township may have their OWN laws in addition to the Federal laws, and good luck on telling them you're OK with the feds if you piss off the local authorities.

It gets confusing. Beyond the several Federal licenses to import, manufacture, deal in or possess explosives, I have held 3 different state's licenses to USE display fireworks, and every one is a bit different.

-----------
(Edit)

The YouTube guy is damned either way.

If he is a legitimate business using explosives and can beat the state possession felony charge by that finding, then his lack of the Federal license(s) he would have needed as a business using explosives will get him a federal felony charge.

It also sounds lime he admitted keeping that sack of powder around longer than the day he got it, and whoever gave it to him also broke the distributing rules.

The dry ice/soda bottle thing is just plain silly, but they have tried to charge high school kids who did that type of experiment IN SCHOOL, WITH A TEACHER KNOWING it was going to be done with legal charges intended by the legislature for terrorism.

It is all fucked up, but slightly better than some other places.

[Edited on 19-1-2018 by Bert]

[Edited on 19-1-2018 by Bert]




Boom.
The explosion removed the windows, the door and most of the chimney.
It was the sort of thing you expected in the Street of alchemists. The neighbors preferred explosions, which were at least identifiable and soon over. They were better than the smells, which crept up on you.
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It is essential that persons having explosive 
substances under their charge should never 
lose sight of the conviction that, preventive 
measures should always be prescribed 
on the hypothesis of an explosion.

Marcellin Berthelot - 1892 Explosives and their power - Page 47
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joseph6355
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[*] posted on 19-1-2018 at 05:22


I synthesized a new 90 g batch of picric acid from ASA. I just precipitated it and it dissolved it in boiling water. Now its colling down.
I mentioned earlier that I was looking for small grain-ish crystals. but with high purity and at the same time obtaining a high yield from ASA, so I was thinking about simply crushing it with a ceramic pestle and mortar, but under water, or at least wet with cold water.

I really wanted to use picric acid, but big crystals scare me, specially if I want high density, because I would need to press them. If I cant use picric acid, then ammonium picrate will do. Ammonium picrate is way less sensitive to friction and impact, so I was thinking about throwing small amounts in the blender and leaving it there until it breaks down to smaller grains, almost like a powder.
Is it safe to crush picric acid?

[Edited on 19-1-2018 by joseph6355]




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