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Zinc
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Making potassium picrate from wood
At http://www.roguesci.org/megalomania/explo/potassium_picrate.... I have read that potassium picrate can be made by dissolving wood in HNO3 and
neutralizing the resulting solution with K2CO3. Is that true? If yes what wood should be used and does the HNO3 need to be concentrated or not?
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=SkyNET=
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Where was the inventor located? The most common tree in their area would be most likely.
The acid should be at least 60-70%
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chemoleo
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Well, of course lignin is highly aromatic, and constitutes up to 1/3 of the mass of wood.
http://en.wikipedia.org/wiki/Lignin
The second most abundant natural component on earth!
Destructive nitration will almost certainly produce picric acid, as well as stypnic acid, and potentially other isomers which are mehtylated etc.
Nonetheless, a lot of the nitrating power will go into nitrating the cellulose, which then produces nitrocellulose.
I should think you'd be much better off using aspirin instead of wood.....
[Edited on 27-6-2006 by chemoleo]
Never Stop to Begin, and Never Begin to Stop...
Tolerance is good. But not with the intolerant! (Wilhelm Busch)
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=SkyNET=
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Interesting! How could styphnic be seperated from picric?
This seems like it could be a very important process.
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ethan_c
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It also seems like a rather risky one, if there happened to be contaminants in the wood or other chemicals present- a mix of styphnic, picric, and
whatever other potentially explosive nitrated compounds wouldn't exactly make me feel comfortable. Just the fact that it's a MIX and you don't know
exactly what you've got in your delicate hands.
It would be interesting to analyze the result of using different woods and in different stages of growth, though, if one could proceed thus without
the possibility of an imminent hospital visit present.
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Chris The Great
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The cellulose would be destroyed in the nitration (and release a lot of NOx in the process).
Still, an interesting idea, though not one I would like to try on my own (unless someone works out all the bugs).
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quicksilver
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"BUgs" indeed...and bark and soil... I once attempted to work with wool and
animal horn in an effort to reproduce the original experiments leading to the isolation of Picric Acid. What a grotesque mess! It did indeed produce
picric acid of a sort. There were what appeared to be extra H in the final product (this was also the case in oil of wintergreen) given that the
material was a darker yellow than PA should be. It could be "cleaned up" quite easily, & the process does indeed yield PA but it leads the
experimenter back to the question of 'why', if more efficient precursers are available would you want to work with once living tissue? It -=IS=- a
mess!
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Rosco Bodine
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Red gum can be efficiently nitrated to picric acid
by a patent process which has been posted in another thread . But in terms of economy and quality of the
product , aspirin is an efficient precursor that is well
proven to be useful . There are many substances
which will produce some picric acid upon nitration but
to be practical the product must be produced in good yield and purity or the task of purification will be made
very difficult . This may be okay if there is no intent to
isolate a pure product as a high quality crystalline form .
But if a highly pure product is desired , there are only a few precursors which are practical and aspirin is the most common and economical .
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Axt
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Heres three articles on the nitration products of wood. Though I dont think picric acid is mentioned, they only concentrate on extraction/analysis of
the cellulose nitrates.
http://rapidshare.de/files/24986594/nitrowood.zip.html
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Marvin
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Mega's page is wrong. Nitration of wood does not yeild picric acid.
Glauber used Indigo and later I think silk.
There are a lot of mistakes in the chemlab, some were pointed out to him years ago.
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Swany
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Salicyclic acid is present in willow bark and has been used as a medication by natives of somewhere, by chewing on it. Nitration of willow bark may
yeild the potassium picrate you seek.
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Rosco Bodine
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Termites eat wood , and possibly then concentrate
the active principle in their droppings .....therefore
take unto thee ten pounds of termite turds and
triturate well with aqua fortis by the light of the
silvery moon ..........   * NOT * !
Naw , on second thought , I just don't think so .
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nuclear
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I found lignine (?) from old mouldered piece of wood. It´s brown and brittle material. I will mix this material with 65% nitric acid. What will then
happen? It seems to me very likely that produce NO2 and decomposition product of lignine... and maybe explosion?? Who know how dangerous is this reaction?
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12AX7
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Y'mean "dry rot"?
I have no idea if mold/mildew eats just cellulose, or everything randomly (hence the spongelike nature).
Tim
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nuclear
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| Quote: | Originally posted by 12AX7
Y'mean "dry rot"?
I have no idea if mold/mildew eats just cellulose, or everything randomly (hence the spongelike nature).
Tim |
Yes, i mean dry rot and not ˝mouldered˝. It`s my mistake. 
Fungi Piptoporus betulinus eat only cellulose and remain lignin. It grow on birch-tree.
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chemoleo
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Nuclear, just do this in small amounts. Explosions during nitrations are very rare, in fact I never heard of one, even when people used crazy high
temp conditions, or whatever else.
It is in solution after all.
Take a couple of grams of dry rot, and once add 65% HNO3 straight (don't expect to much), and once use first H2SO4 96% on it, and THEN add the HNO3.
Then proceed similar to PA synthesis (which requires heating to 80 deg C or so IIRC... but check it up). NO2 evolution is to be expected, but that is
normal with phenols.
But do this outside. With small amounts you will be safe for sure.
Please post the results!
Never Stop to Begin, and Never Begin to Stop...
Tolerance is good. But not with the intolerant! (Wilhelm Busch)
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Rosco Bodine
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If I had to make a guess ......the reference to
" wood " is a typographical error for " wool "
Baaaaa .. Baaaaaaa .....
Baaaaaa Baaaaa Black Sheep ,
Have you any * WOOL *
Yes sir , yes sir , three bags full
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Sickman
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Rosco is right!
The literature repeats over and over that our early fathers obtained picric acid from the nitration of wool, indigo,
aloes, "resin" and even animal horn. The key word is "obtained". The yeilds are so horrible with such raw materials and the contamination is so
outrageous that it is not worth even trying to prepare a lab sample from such methods let alone any significant amounts.
Better stick with aspirin, not only is it cheap, but because it's regulated by the government, it is extremly pure. Which as Rosco says in other
post's "best results for yield and purity are obtained only from the purest precursors!"
Edit: Of course I mean aspirin purified from it's alcohol insoluble binders!
[Edited on 16-7-2006 by Sickman]
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S.C. Wack
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What Mega says on his page is straight out of Fedoroff.
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Rosco Bodine
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Federoff and Urbanski are both wrong more often than Rosco
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nuclear
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| Quote: | Originally posted by chemoleo
Take a couple of grams of dry rot, and once add 65% HNO3 straight (don't expect to much), and once use first H2SO4 96% on it, and THEN add the HNO3.
Then proceed similar to PA synthesis (which requires heating to 80 deg C or so IIRC... but check it up). NO2 evolution is to be expected, but that is
normal with phenols.
But do this outside. With small amounts you will be safe for sure.
Please post the results! |
I´m not mean nitration but decomposition of lignin (first this and maybe then nitration ). HNO3 is strong oxidant and i´m interest for decomposition products of lignin, not only for picric acid. (theme on lignin is there in
˝energetic materials˝, and i posted here).
I will use only conc. HNO3 without H2SO4 for decomposition. Then i will try isolate some products (phenolic compound, monolignols such as coniferyl
alcohol, or what will result of it).
And then i will post the results here.
[Edited on 17-7-2006 by nuclear]
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Nicodem
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If you guys check the partial structure of lignin that Chemoleo posted you can notice that not a single benzene ring has only one -OR (R: H or Me)
group, hence there is no way picric acid can be formed. This would require a mechanism capable of reductively substitute one -OR by -NO2 (the
oxidation state of the C they get attached to is +1 vs. -1). No such mechanism is known (not surprisingly given that HNO3 is an oxidant).
On the contrary, tyrosine, an amino acid in proteins (wool, silk, horn etc.) can be dinitrated while still part of the protein and then the side chain
( Ar-CH2-CH(NH-)-CO- ) gets easily oxidized till you end up with 4-hydroxy-3,5-dinitrobenzoic acid which can have its -COOH group decarboxilated by
NO2+ ipso substitution (the same process that allow for the synthesis of picric acid from salicylic acid). Anybody ever got those damn picric yellow
colored HNO3 stains on the skin? But needless to say, that given the small amount of tyrosine in proteins in general, such a method must give all kind
of crap and only a ridiculous amount of picric acid.
So, I'm afraid Rosco is correct in assuming a typographical error.
Anyway, if we suppose the nitrated benzene rings of lignin also get their benzylic alcohol sites claved and oxidazed to -COOH, there could also happen
an analogous decarboxilation by NO2+ ipso substitution resulting in a mixture of compounds like 2-methoxy-4,6-dinitrophenol and
2-methoxy-3,4,6-trinitrophenol. However it seams near to impossible for me to envision conditions where the demethylative oxidation of these aromatic
rings to the appropriate o-benzoquinonic structures would be prevented. It is not that simple to polynitrate benzene rings with 1,2- and 1,4-
positioned -OR groups (where at least on of the R is H). For this reason one can efficiently trinitrate resorcinol but not pyrocatechol or
hydroquinone. So I’m afraid that nitration of lignine yield only some black crap.
…there is a human touch of the cultist “believer” in every theorist that he must struggle against as being
unworthy of the scientist. Some of the greatest men of science have publicly repudiated a theory which earlier they hotly defended. In this lies their
scientific temper, not in the scientific defense of the theory. - Weston La Barre (Ghost Dance, 1972)
Read the The ScienceMadness Guidelines!
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Rosco Bodine
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Hehehehehe chuckle chuckle ......
Rosco breathes on fingernails and buffs them against labcoat , then inspects for the quality of the SHINE ,
yeah ...that'll do .
We all shine on .....
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nuclear
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Nicodem, nitration of lignin isn´t my intention.
Maybe you know other better oxidising or reducing reagents for destruction polymer chain?
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Nicodem
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You should first describe what is that you want as a product. There are many methods of using lignin as a source for certain organic compounds by
acidic, basic, reductive or oxidative cleavage under various conditions described in literature. Needless to say that isolating the products is the
most difficult part. Nevertheless, there are industrial processes for using lignin as a starting material (for example, vanillin preparation from the
fermentation of lignin). Most literature describes enzymatic cleavage. I know only of few researches that use chemical means and they are not suitable
to a hobby chemist and are not economic either.
Two examples of acidic, reductive cleavage:
http://www.dfrc.wisc.edu/DFRCWebPDFs/1998-Lu-JAFC-46-547.pdf
http://jagor.srce.hr/ccacaa/CCA-PDF/cca2000/v73-n3/cca_73_20...
I guess that you could search by yourself and find something more appropriate. Searching the patents would also help.
Perhaps one could get vanillic acid by simply boiling lignin with a KMnO4 solution acidified with some H2SO4. The product should be extractable from
the reaction mixture. However the yield would be very low and highly dependent on the lignin source (different types of trees have a different lignin
- the more crossliniked ones give lower yields). A simple cleavage with ~30% H2SO4 at reflux might also give some interesting products, but they would
not be easy to extract. And then you would still have the problem of separating the products from the obtained mixture. You could only hope that one
product prevails enough to make recrystallization feasible otherwise there remains only the chromatography.
…there is a human touch of the cultist “believer” in every theorist that he must struggle against as being
unworthy of the scientist. Some of the greatest men of science have publicly repudiated a theory which earlier they hotly defended. In this lies their
scientific temper, not in the scientific defense of the theory. - Weston La Barre (Ghost Dance, 1972)
Read the The ScienceMadness Guidelines!
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