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Axt
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[*] posted on 5-12-2004 at 03:28
Pseudonitrosites


Here's a funny one. Made by the interaction of N2O3 with an unsaturated hydrocarbon. Patent US1473825 describes pseudonitrosites based on ethylene and propylene, formed by passing the gas through ether, where its mixed with N2O3 (mix of NO & NO2) which attaches forming a nitro group as well as a nitroso group which condense through a strange peroxidic bond into a dimeric structure. Both ethylene and propylene derivatives are suggested for use as base charge in detonators.

PATR 2700 gives reference to a couple more, based on butadiene and cyclohexene. It also mentions that the ethylene derivative is comparable in powder and brisance to tetryl, that aint nothing to sneeze at! Rhodium used to have the sythesis of a pseudonitrosite based on propenylbenzenes, not explosive but same procedure.

Ethylene can be made by dehydration of ethanol with sulphuric acid, CH3-CH2OH + H2SO4 → CH2=CH2 + H2SO4.H2O. N2O3 can be made by the reaction between copper (or other metal) with nitric acid, 2 Cu + 6 HNO3 → 2 Cu(NO3)2 + 3 H2O + N2O3.

Not wanting to go the EtOH/H2SO4 route (bad experiances!) I looked at MAPP gas to provide the reactive gasses. Both Propyne (CH3-C≡CH) and Propadiene (CH2=C=CH2) are likely to act on nitrogen oxides, propyne goes to dinitropropylene when reacted with NO2, but I dont know what whether NO will give it the pseudonitrosite structure as well. If propyne only has one double bond attacked its likely that propadiene will only be attacked at one bond as well, forming a different isomer then the propyne derivative of propylene pseudonitrosite. These explosives should have performance between thatof TNT and tetryl. If that made no sense, heres what I think they look like:

<center><img src="http://www.sciencemadness.org/scipics/axt/pseudonitrosites2.jpg"></center>

For the N2O3 generator, I used a glass jar containing lengths of 15mm copper pipe, through one tube in the jar was injected nitric acid, with the N2O3 coming out another tube. I fed the gasses into an upturned test tube where they mixed before bubbling out through an ether solution.

<center><img src="http://www.sciencemadness.org/scipics/axt/nitrosite.jpg"></center>

The solution turned dark green and a small precipitate of white crystals formed, no crystals formed within the testtude and a considerable amount of the MAPP gasses dissolved in the ether (it "boiled" at 22°C), therefore I dont think mixing the gasses before bubbling is necessary. The small yeiled was filtered out and dried. On ignition they turned green and burnt lazily, the yield wasnt large enough to try detonation, but at least it seemed to work.

It would be worth trying it in a more suitable vessel (measuring cylinder etc.) to get a greater yield. I tried bubbling MAPP through a concentrated nitrous acid solution (NaNO2/H2O + H2SO4), it turned dark purple but no precipitate when dunked into water.<br><br>

[Edited on 9-12-2005 by Axt]
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[*] posted on 5-12-2004 at 05:29


Very interesting! Can it get even more exotic?

I wanted to say something about the preparation of N2O3 and ethylene.

The reaction of HNO3 with copper gives either NO or NO2, depending on the concentration of the HNO3. Only at narrow concentration margin, it gives N2O3.
As the HNO3 reacts, its concentration drops and the composition of the gas changes.
Your gas looks very dark red, this indicates that it consists mainly of NO2. Your acid was too concentrated!

The reaction of sodium nitrite with an acid gives pure N2O3.

2 NaNO2 + 2H+ -----> 2Na+ + 2HNO2
HNO2 decomposes:
2HNO2 ----> H2O + N2O3

Use dilute H2SO4 as the acid.
I once made N2O3 with this reaction and it was a faintly yellow gas (it became deep red on contact with air though, as the NO was oxidised to NO2 by atmospheric oxygen).

Now about Ethylene:
Sulfuric acid isn't needed, other dehydratation catalysts work, too.
Plain simple SAND is a suitable catalyst when heated strongly.
Just pass ethanol vapors (air-free!) through a strongly heated glass pipe containing some sand.
Then lead the produced gases through a condenser.
Residual Ethanol condenses, and the Ethylene can blow up a balloon for storage (if the whole apparatus is air-tight and under slight pressure).
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[*] posted on 5-12-2004 at 06:13


Quote:

The reaction of sodium nitrite with an acid gives pure N2O3.

2 NaNO2 + 2H+ -----> 2Na+ + 2HNO2
HNO2 decomposes:
2HNO2 ----> H2O + N2O3

Use dilute H2SO4 as the acid.
I once made N2O3 with this reaction and it was a faintly yellow gas (it became deep red on contact with air though, as the NO was oxidised to NO2 by atmospheric oxygen).


I don't think that that synthesis is correct. First of, N2O3 is a bluish liquid at something lower than 5 deg celcius. Secondly HNO2 IIRC does not decompose into N2O3. It decomposes into a mixture of oxides, mainly NO and NO2 (the decomposition product of HNO2 is a brown gas).

The synthesis of N2O3 is usually carried out by reacting an excess of NO(g) with oxygen or using a mixture of NO and NO2, both of which under cooling give N2O3 in the liquid state. Cooling is usually carried out in a dry ice/alcohol bath, although an ice/salt bath under -10 to -5 deg celcius should work also. (If you afford you can also use liquid nitrogen, in which case you'll obtain solid N2O3)

For the preparation of pure NO the reaction between acidified iron (II) sulfate (VI) [ferrous sulphate] with sodium nitrate (III) is usually used. Note that the method used by Axt to produce NO is also a good one. garage chemist, where are the dark red fumes in the picture? I might be going blind :P but I see no such fumes. Well anyway the rxn between dilute (i.e. <50%)nitric acid with Cu fillings gives NO too - preferably excluding oxygen from the container where the rxn mixture is present.

Quote:

Now about Ethylene:
Sulfuric acid isn't needed, other dehydratation catalysts work, too.
Plain simple SAND is a suitable catalyst when heated strongly.
Just pass ethanol vapors (air-free!) through a strongly heated glass pipe containing some sand.
Then lead the produced gases through a condenser.
Residual Ethanol condenses, and the Ethylene can blow up a balloon for storage (if the whole apparatus is air-tight and under slight pressure).


Also, you're assuming that sand is completely SiO2, which it is not. This method of preparation requires high pressures and high temp IIRC, and would be rather complicated. Dehydration of the alcohol by sulfuric or phosphoric acid would be preferred. Also, correct me if I'm wrong, but SiO2 is not used in isolation as a catalyst but together with Al2O3.

[Edited on 5-12-2004 by Esplosivo]




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[*] posted on 5-12-2004 at 06:29


Sorry that pictures confusing people! Its actually NaNO2 injected with 30% H2SO4, I tried that first. I dont think it matters that its not N2O3 as such, rather NO/NO2, as in its gasseous state its always predominatly a mixture anyway.

Yeh, so they are red fumes (not copper pipe as your seeing Esplosivo ;) ) but its also relatively equal NO/NO2 as its formed from the nitrite!

I seemed to get a better yield using the copper/nitric method, and is less of a waste and more OTC. But I have only done it twice so how repeatable it is I dont know.

Orchards use ethylene generators to ripen fruit, wonder what catalyst they use? maybe its just sand as you mentioned Garage chemist. Its ethanol + a solid.

[Edited on 6-12-2004 by Axt]
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[*] posted on 5-12-2004 at 06:40


Well then I owe some apologies. Give the method I mentioned a try Axt. The one in which rxn of Cu with dilute HNO3 gives NO which is in turn reacted in the cold and in excess with air. Could work out better.

I have no idea what the ethylene generators use, but certain catalytic conversions do require pressure and not only heat if it were SiO2. Again I may be wrong, but it seems strange that simply boiling an alcohol with SiO2 will dehydrate it to the alkene.

Edit: Typo

[Edited on 5-12-2004 by Esplosivo]




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[*] posted on 5-12-2004 at 10:28


When I was looking for methods of making carbon tetrachloride in the chemistry abstracts, I ran across something similar to this. The reaction of tetrachloro ethylene with N2O3 or with N2O4 yields Nitro and nitroso groups added onto the bond that's broke. A small percentage of CCl4 is also formed though, hence my finding of the article.



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[*] posted on 5-12-2004 at 13:24


Quote:
Again I may be wrong, but it seems strange that simply boiling an alcohol with SiO2 will dehydrate it to the alkene.


You are right, boiling ethanol with SiO2 doesn't make any reaction.
But I said that Ethanol VAPORS should be run over hot SiO2!

In the KOSMOS Chemistry set, ethylene is made via this method. I tried it and it works!
The sand needs to be very hot.
The gas generator is a long horizontal test tube, wit 10- 20 ml of ethanol (absorbed into sand) in the lower part and some dry sand in the upper part of it.
The dry sand is heated strongly and the ethanol- wet sand is heated slightly so that the ethanol vaporises and the fumes pass over the hot sand.
The gas is collected over cold water, in an inverted cylinder. Residual ethanol condenses into the water.

Try it out if you don't believe.
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[*] posted on 5-12-2004 at 13:31


The methods for producing ethylene that I've seen use a slurry of sand and H2SO4 with EtOH, I believe the sand just helps to moderate the reaction. But it may work catalytically. I don't think it would work alone though.



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[*] posted on 5-12-2004 at 14:43


Sand WORKS ALONE, I will scan the synthesis from the KOSMOS manual tomorrow and post it here if you don't believe.
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[*] posted on 5-12-2004 at 14:55


I misread what you'd posted. I thought that you were speaking of a liquid/solid phase but you were talking about gaseous EtOH run over hot SiO2, yeah, that's a common type of reaction in the petroleum industry. I was too busy thinking about other methods of reaction involving the slurry of SiO2 w/ H2SO4. My mistake.

[Edited on 12/5/2004 by BromicAcid]




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[*] posted on 5-12-2004 at 17:22


I just read through the patent, and it seems that the tricky bit in part is the N2O3.
Firstly it makes no mention how 'nitrogen sesquioxide' (N2O3) was produced. Secondly, and more imporantly, it states that N2O3 are used in the case of ethylene, but with other unsaturated hydrocarbons such as propylene , a mixture of N2O3 can be used together with other nitrogen oxides.
I wonder why the author came to that conclusion - and that of course immediately makes me wonder how he prepared the N2O3 in the first place - i.e. if N2O3 is a mixture of NO and NO2 at the temperatures employed (5-20 deg C), this already *constitutes* a mixture of nitrogen oxides!

Looks like it might be worth investing a bit of research in how N2O3, in the correct proportions can be made - i.e. I always had the impression that Cu, with HNO3 predominantly forms NO, where the NO2 is only formed with atmospheric oxygen.

Then - the structure of hte compound - did anyone notice, it is the peroxide circularised to the N-N (as in hydrazine), in a FOUR-membered ring?
From all I know about nitrogen, its unstable bonding to each other, coupled to a peroxide bond shouldn't really possible. Interesting also that the author proposes the structure (as shown above by Axt), but points out that it does NOT necessarily reflect the real structure.
Oh well... I have my doubts. Unless someone knows other examples where this fourmembered ring was shown to exist - will happily be educated :)

Then, with regard to ethylene -
I have a proper prep for it, from Gattermann. I think Mephisto uploaded it too, but it's in German. Preparation is by dehydration of ethanol with H2SO4 - will post it if interested. It's a prep designed for the organic chemist - i.e. a proper one, not some quick class room demonstration thing.
Also, I remember reading about dehydrating ethanol with heated rocksil wool - on that note, what the heck is rocksil wool? Glass wool or something?

EDIT:
I forgot, how do you know that the remaining double bond in the propene adduct (derived from the propine) does not react once again with further N2O3, to yield the fully saturated multi-nitro(so) adduct? But then, it might precipiate before it reacts.

One further thing - the author also makes no mention why N2O3 is preferred, and why not NO on its own or NO2 on its own (the latter being N2O4 at low enough temperatures). The point I am trying to make is - maybe it forms one type of adduct with NO (i.e. dinitroso ethylene), and another with NO2 (dinitroethylene adduct), while N2O3 forms the mixture (i.e. as in the structure above).


[Edited on 6-12-2004 by chemoleo]




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[*] posted on 5-12-2004 at 18:09


The structure is also in PATR and in Rhodium. What are the alternatives? a straight dioxime peroxide (=N-O-O-N=)?

I think peroxides between two nitrogens are quite stable in contrast to C-O-O-C, check dioxime peroxides, the most simular structure I can think of, containing two carbons in a six membered ring -(C=N-O-O-N=C)-.

Another interesting find, the ether after evaporated yielded an amber coloured liquid, more dense then water and insoluble. Im assuming its the dinitro compounds.

<center><img src="http://www.sciencemadness.org/scipics/axt/dnp.jpg"></center>

EDIT: yeh, so the pic above shows that here is two products forming, theres another reference in PATR for ethylene derivative that uses N2O4 for the same product. I dont think it matters as the pseudonitrosite is the only precipitate, so easily isolated from the other products.

EDIT 2: Upload the ethylene synth!

EDIT 3: The example I found for dinitro derivative for propyne only attacked 1 = bond, thats why I think its taking on that structure. If it were to attack them both you would end up with some crazy polymer.

[Edited on 9-12-2005 by Axt]
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[*] posted on 6-12-2004 at 12:45


Here's the Ethylene Synthesis from Ethanol + Sand.
It's "Versuch 438" and the apparatus picture.
Pay attention on the placement of the burner!

Sorry for the crappy picture.

Attachment: ethen001.tif (459kB)
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[*] posted on 7-12-2004 at 20:00


Thanks, seems almost too easy.

Regarding the liquid product, it cannot be ignited, so I tried to make its salts to see if it was indeed the nitro's.

Some water was poured over the oily yellow liquid, then dilute NaOH was added until its sodium salt had dissolved into solution. Into this was poured solutions of lead acetate and silver nitrate. Precipitates formed immediately, black for silver and orange for lead.

The lead salt explodes very feebly, but the silver salt hold more promise, exploding with a thump, but leaving while "snowy" residue (It could be that it wasn't fully dry). The silver salt is shown below.

<center><img src="http://www.sciencemadness.org/scipics/axt/sdnp.jpg">
<a href="http://geocities.com/roguemovies7/">MOVIE</a></center>

[Edited on 9-12-2005 by Axt]
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[*] posted on 10-12-2004 at 11:42
Other Pseudonitrosites!


I read something very interesting today, in Gattermann:

We all (should) know that nitromethane (alkanes) can form nitronate, i.e. it acts as a weak acid. This acidity increases with more nitro groups attached, i.e. nitroform (HC(NO2)3) has a pKa <1, which is comparable to mineral acids.

For instance, H3C-NO2, in the presence of a base, is in equilibrium with this structure H2C=N(O-)OH.
This means, the latter form (called the aci-form) can react with other electrophilic agents other than the proton, i.e. Br or nitrosyl.

HNO2 for instance reacts with nitroalkanes to form nitrolic acids, which are colourless but form deeply red salts with alkalis (which I am sure are of an energetic nature when they are lead salts).
Secondary nitroalkanes (such as 2-nitropropane) react with HNO2 to form pseudonitrosites, which are green or blue (!!) when reacting with with alkalis (this seems to be implied)

Primary nitroalkanes:

HONO + H2C=N(O-)OH (nitromethane) ---(-H2O) ----> O=N-CH2-NO2

Secondary nitroalkanes:

HONO + (CH3)2C=N(O-)OH (2-nitro propane) ---> O=N-C(CH3)2-NO2


Damn, I wish I had some nitromethane!

So, Axt, this may be something you'd want to try.

Dissolve nitromethane in NaOH (WEAK), and add KNO2 in stoichiometric amounts. Acidify with H2SO4 or something. This should liberate the HONO, which'd react with the aci-form of nitromethane, forming nitrolic acid (Which is colourless).
To this, add i.e. KHCO3, and see if the solution turns red. This should be the salt of nitrolic acid. I know nothing of its solubility however.
Lead acetate (this is likely dangerous) might be another salt to test whether you can preciptate the nitrolic acid salt.

By the looks of it, however, nitrolic acid should be fairly energetic on its own!

Re. 2-nitropropane, this should be also fairly interesting, and the colour change to green/blue should be fairly obvious.

To sum it all up: HNO2 can be used instead of NO/NO2 gas to react it straight with nitroalkanes to obtain pseudonitrosites :)

[Edited on 10-12-2004 by chemoleo]




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[*] posted on 10-12-2004 at 20:53


Did you get its structure right Chemoleo! I think its an oxime, where you have a nitroso. Even still, methylnitrolic acid & its salts still possess perfect OB.

HON=CH-NO2 --> CO2 + H2O + N2

I have looked into nitrolates before, but with nitromethane, the conclusion was you can't create its sodium salt without it reacting to methazonic acid (HON=CH-CH2-NO2). Supposedly you can create it directly from HONO + NM, just havnt found the correct procedure. I have made attempts.

A vague reference is given in PATR, very unstable towards heat. Exploding below 100°C. US2401268 gives methods for everything but the nitromethane derivative. This reference would be most interesting: V. Meyer & E.J. Constan, Ann 214, 334 (1882).

Nitrosation of primary amines supposedly goes to nitrolic acids as well. I have no further info on this. Perhaps a nitrolic acid thread is in order!
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[*] posted on 10-12-2004 at 22:42
The nitromethane derivative


from an earlier (and in English) Gattermann-Wieland. I've been meaning to scan it, it's my favorite of 36 chemistry books that I have on the shelf. But right now I'm putting Vogel's Quantitative Chemical Analysis (1989) and Qualitative Inorganic Analysis (1979) together. That'll keep me busy for awhile.

"Experiment.--Methylnitrolic acid--Nitromethane (3.2 g.) is
dissolved in 30 c.c. of ice-cold 2 N-sodium hydroxide solution and a
concentrated solution of sodium nitrite (3-5 g.) is added. Without
further cooling 4 N-sulphuric acid is run in from a dropping funnel
until the solution, which is at first deep red, has just become yellow
and does not yet turn potassium iodide-starch paper blue. The
mixture is now extracted twice with ether and the aqueous layer is
again cooled. Sulphuric acid is again dropped in until the evolution
of nitrous acid becomes distinct and the solution is then again made
so strongly alkaline with 5N-sodium hydroxide solution, that a
deep orange colour results. Once more the solution is acidified to
such an extent that nitrous acid cannot yet be detected, and is again
extracted twice with ether. The combined ether extracts are dried
for two hours over calcium chloride in a vessel kept on ice. The
ethereal solution is now transferred to a small round flask and the
solvent removed by distillation with a capillary in vacuo on the water
bath at 15°-20 °. A residue consisting of about 1 g. of well-crystal-
lised pale yellow methylnitrolic acid remains. The preparation de-
composes in the course of a few hours. Test its behaviour towards
alkalis."

It goes on to make fulminic acid and silver fulminate with HNO3 and AgNO3.

Attachment: methylnitrolic_acid.pdf (142kB)
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[*] posted on 11-12-2004 at 05:03


Hmmm.

Quote from US2401267 "The foregoing reactions are usually carried out by dissolving a nitroparaffin - excepting CH3NO2 - in aqueous alkali, then adding an organic nitrite and acidifying in the cold with a mineral acid".

Interestingly this was deleted in the nearly identical patent I gave above, which is dated 1 month more recent. The pseudonitrosites are mentioned in it as well, but as the "pseudonitrole" monomer. I'll try with NaOH and see what happens, though I'm not sure if I will be able to tell the difference between methynitrolic and methazonic acid.

Couple quotes of interest:

PATR 2700 "these red salts are usually very powerful explosives".

JACS article "Sodium propylnitrolate decomposes slowly with time, as do the other alkylnitrolates"

Hopefully the heavy metal salts of methylnitrolic acid are more stable.
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[*] posted on 12-12-2004 at 09:07


Using the method Mr Wack posted, seemed to go to plan, turning from yellow to red, then back to yellow on addition of H2SO4. Extraction with ether an evaporation in the sun resulted in decomposition and evolution of N oxides, no solid product remained.

The ether extract was mixed into a weak NaOH solution, it turned orangey red almost immediately. Straight NM/NaOH turns this colour as well on formation of methazonic acid, but it happens much slower in the concentration I used.

Lead salt was precipitated from lead acetate. On drying it wasn't energetic at all. The Pb salt precipitated from straight NM/NaOH does this as well, if its chucked onto a hotplate damp after filtration it explodes with a bang, but after dried, it looks the same, but just smoulders.

So far, the methylnitrolates look too unstable to even hold novelty value, if that is indeed what it was.
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[*] posted on 12-12-2004 at 19:31


So essentially it looks like the reaction of the aci form of nitromethanol with HNO2 worked?

I.e. once you added the KNO2 to the NaOH/NM, and acidified this with H2SO4 (how strongly? did you take care of stoichiometry?), the red colour disappeared? And once you added base once again, it become red?
This would indicate the nitrolate indeed, although of course it could just indicate the plain nitronate.
Might be good to really sort out the stoichiometries.
As a control experiment, it might be best to do this with 2 nitropropanol, as this should form a green salt.

Anyway - as to the lead salt of the nitrolate - did it occur to you that you are precipitating PbSO4 as a first thing - as it is highly insoluble ;)? No wonder this wasn't energetic - most likely this was 90% PbSO4 and 10% Pbnitrolate.
Hmm - next time maybe acidify with HNO3, as the lead salt is soluble, while the lead nitrolate hopefully isn't. Let's hope the HNO3/NO3- doesn't somehow react with the nitrolate - I wouldn't see how, either.

As to the wrong structure you mentioned - I dont think it is, but I see why you are confused.
I.e. this is a case of tautomerism , where the HO-N=CR2 tautomerises to O=N-CHR2.
With this I can see why they called it pseudonitrosites (i.e. nitroso is N=O-C, while HON=C is oxim). I guess this tautomerism won't be possible with tertiary nitroalkanes as there isn't any hydrogen available on the neighbouring carbon... anyway... :) tautomerism explains the confusion.

Oh... and nice to see that my proposed synth from above pretty much overlaps with the published one ... there is yet hope for me! :)

[Edited on 13-12-2004 by chemoleo]




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[*] posted on 12-12-2004 at 22:24


Quote:
Originally posted by chemoleo
So essentially it looks like the reaction of the aci form of nitromethanol with HNO2 worked?


Yes, it seemed to, unless the extract was methazonic acid, in which case I think the same same colours would show. NM's so indecisive it annoys me greatly. Methazonic acid also readily decomposes to a red resin, so colours arnt a good indicator.

Quote:
I.e. once you added the KNO2 to the NaOH/NM, and acidified this with H2SO4 (how strongly? did you take care of stoichiometry?), the red colour disappeared? And once you added base once again, it become red?
This would indicate the nitrolate indeed, although of course it could just indicate the plain nitronate.


As far as I know the nitronate is white and methazonate red, thats why its confusing. It turns red on addition of H2SO4 (as the supposed sodium nitrolate forms), then back to yellow as it liberates the free acid. That all goes to plan.

Quote:
Anyway - as to the lead salt of the nitrolate - did it occur to you that you are precipitating PbSO4 as a first thing - as it is highly insoluble ;)? No wonder this wasn't energetic - most likely this was 90% PbSO4 and 10% Pbnitrolate.


I precipitated from the ether extract, which should be free of sulphate (how soluble is H2SO4 in ether?), but not free of NM/methazonic impurities, thus the indecisiveness in the product. I hate NM, really I do.

[Edited on 13-12-2004 by Axt]
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Rosco Bodine
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[*] posted on 26-4-2005 at 22:04
Ethylene production methods


Scraps of low density polyethylene , such as pieces of an empty milk jug will reportedly depolymerize to ethylene gas , if the material is slowly heated to melting and held at a temperature just above the melting point , but cooler than the point at which it forms a smoky fog above the molten material or causes darkening of the melt .

I haven't tried the depolymerization on melting of LDPE , but this would seem to be a very simple method and would utilize a material which usually is discarded as trash .

http://mattson.creighton.edu/C2H4/index.html


With regards to ethylene manufacture from ethanol and sulfuric acid , from what I have read the production of both ether and ethylene is performed in a similar way , but the temperature is kept slightly higher when ethylene is the desired product .

Ethylsulfuric acid is the intermediate in each reaction .

For an ethylsulfuric acid kept 130-140 C ,
it would seem the product which distills is a mixture of diethyl ether and ethylene ,
while if the ethylsulfuric is heated more strongly to 150 - 170 C , then the principal product is ethylene .

http://www.frogfot.com/synthesis/dietether.html

http://designer-drugs.com/pte/12.162.180.114/dcd/chemistry/e...

[Edited on 27-4-2005 by Rosco Bodine]
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neutrino
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[*] posted on 27-4-2005 at 12:54


Even a small amount of moisture will prevent polymerization in industry, so a little steam here should do the job.:D
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Rosco Bodine
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biggrin.gif posted on 27-4-2005 at 14:52
A pressure cooker maybe with a little water in it ?


Wow what a brainstorm , if it would work :D

The recyclers use superheated steam under pressure to depolymerize plastics for remanufacture .

LDPE melts at ordinary autoclave / pressure cooker temperatures I think .

I would have to double check this melting point for LDPE , unless somebody has it handy .

Update : most references I am finding give a melting point of 248 F . So far I am finding no reference to the depolymerization temperature other than it occurs below the boiling point of the melt .

Anyway , an ethylene generator for making a fair amount of ethylene :D could be as simple as a pressure cooker with
some distilled water , heated to a precise
temperature and pressure , which would be regulated by the relief valve .

Presto ! A stream of ethylene and steam
being discharged . A condenser could be used to strip the moisture leaving pure ethylene gas for convenient use in synthesis .

The idea of making a stable and practical energetic material on a par with tetryl , from nothing but empty milk jugs and nitric acid and potato starch as feed materials has a certain appeal if it really is so easily done .

[Edited on 28-4-2005 by Rosco Bodine]
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[*] posted on 29-4-2005 at 22:43


Milk jugs, starch, nitric ..... and ether :(

Perhaps another solvent could be used, any ideas? Though I think the pseudonitrosite procedure (if memory serves) on rhodium called for starting fluid (ether/hexane), so thats a possible source. I guess If you had ethanol/H2SO4 you could go that route but it is a lot of screwing around.

The german reference "N. J. Demjanow, Chemisches Zentralblatt, 1899 I, pg. 1064" may be interesting and provide a better more detailed procedure.

Perhaps acetylene can be substituted for ethylene, if it were to dimerise into C4H4N4O6 it would at least achieve CO balance.
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