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Author: Subject: Crystal growth and preparative details of nitrophenols (stypnic, picric acid)
quicksilver
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[*] posted on 27-9-2005 at 07:32


Quote:
Originally posted by Quince
Thanks, that made it all clear.

Why do people seem to prefer the long needle-like crystals? Wouldn't they be more sensitive, due to breakage when moving and packing them?

Also, during boiling down for the second batch, it seems some picric acid is evaporating along with the water, as a cool surface above the boiling liquid accumulates a yellowish condensate from just the steam, without there being any spray (even if I remove from the heat so boiling stops).

In regards to storage, is alcohol as effective a desensitizer as water? I ask as it's much faster to dry alcohol.

[Edited on 27-9-2005 by Quince]


I don't know if you could determine if you are loosing material if the PA is still is in solution; it is a dye after all and yellow solution will be everywhere. Measuring weight when dry is the only sure method to know if you are actually loosing material in evaporation (I think it's doubtful if we are only speaking of evaperation).
Allowing PA to remain moist and off of any threads or frictional surfaces on the final container would maintain a safe environment for the most part regardless of size or shape. Some compounds [primaries and secondaries] would be problematic with crystals of size but TNP, TNR, or TNPG don't present that issue and especially when moist. But even so, the sensitivity of nitrated phenols or benzenes is not that high especially in comparison to the nitramines as a group) On that note the nitrate ester nitramines such as Dinitrooxydiethylamine Nitrate (DNAN) is famous for being detonated from impact, etc as a secondary. But it's not that pretty or useful in a variety of areas like TNP.
The use of a solution of greater solubility such as alcohol would possabily retain more of the product in solution. But for the purpose of simply drying it and using same, it's perhaps a more convienient way to go. But for myself I would be hesitant only because I may loose some of the better looking crystals when it reforms (no big deal to most folks). However, that is with nitrated phenols....there are some compounds that it has been said, could form larger crystaline structures via alcohol and it would become a danger (i.e. lead azide).

[Edited on 27-9-2005 by quicksilver]




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[*] posted on 11-10-2005 at 20:23


Quote:
Originally posted by Quince

Is there any advantage to using HNO3 instead of nitrates?


Using nitric acid results in a thinner mixture due to the absence of bisulfate byproduct from the reaction of the nitrate and the sulfuric acid , and a lesser amount of sulfuric acid is required since that amount which would be reacted with the nitrate to produce nitric acid in situ is not needed when the nitric acid is supplied externally . The additional amount of sulfuric acid needed as a solvent an / or liquid carrier for the solids in the nitration mixture so that the mixture remains stirrable is also reduced when the nitric acid is supplied externally .

But all things considered , it may not be as efficient to use nitric acid as to use the solid nitrate , or nitrate solution in nitric acid or water , and sulfuric acid in the increased amount required .

The usual opinion which has been expressed is that nitric acid has a higher nitrating effect than solid nitrate mixed with sulfuric acid , but for nitrations of certain materials it has been observed by experiment that higher yields are produced by the solid nitrate and sulfuric acid mixture than for similar molar strength nitrating mixtures using fuming nitric acid d. 1.5 . Urbanski supports this observation about the evident higher nitrating effect of solid nitrates mixed with sulfuric acid as a generality , but in my own experiments it tends to be somewhat reaction specific and depends on what thing is being nitrated , whether it is nitrated better by solid nitrate with sulfuric acid , or a mixed acid nitrating scheme using nitric and sulfuric acids in
whatever sequence or proportions .

Different solid nitrates have different nitration strengths or activity in combination with sulfuric acid . See the attached file for a comparison of various solid nitrates activity as nitrating agents increasing above nitric acid .

In my opinion it is evident that some amount of nitrosylsulfuric acid is formed in the nitrating mixture when solid sodium nitrate is used for the nitration of sulfonated ASA in 92% sulfuric acid .
When the completed nitration mixture is allowed to cool to about 92C and cautiously diluted with water streamed onto the inside walls of the flask , stirred into the mixture , hydrolysis of the nitrosysulfuric acid occurs and a steady evolution of NO2 and perhaps some nitric acid vapors appears . This hydrolysis is
exothermic and the products have oxidizing properties , which is likely the mechanism responsible for unexpected
" runaway reactions " which sometimes are observed in nitration mixtures which are near or at completion of the nitration .
In nitration mixtures where the water content is low , the nitrosylsulfuric acid accumulates , and the stability of the mixture depends upon the temperature and the water content , so the nitration process completion temperature and the composition of the spent acids must be deliberately controlled to enable the hydrolysis to be done by manual dilution of the finished nitration mixture , instead of occurring spontaneously at some unfavorable temperature and water content in an unfinished nitration mixture , resulting in a final nitration stage runaway . It requires some trial and error process engineering to establish the proportions of safe and efficient mixtures and determine the reaction temperatures and times which are optimum for nitrations of specific materials .

With regards to the mixed nitrates eutectics which I mentioned earlier in connection with the possible salting effect that produces anomalous increases in solubility , I found one tertiary eutectic in Urbanski 3 , page 257 .

66.5% NH4NO3
21% NaNO3
12.5% KNO3 f.p. 118.5 C

I am uncertain if this mixture exhibits the salting effect for increased water solubility in the same proportions as for the effect on lowered melting point for the eutectic . The proportions for the salting effect are posssibly different and
I have no idea where such solubility anomalies are charted for reference , but such mixtures do exist .

Attachment: Page 46 from Urbanski vol. 1.pdf (8kB)
This file has been downloaded 2317 times

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[*] posted on 13-10-2005 at 07:03


Quote:
Originally posted by Quince
Why do people seem to prefer the long needle-like crystals?


Purity , and identification , ease of filtration and drying , bulk density , and sensitivity to initiation are all favored by production of the picric acid in a very pure and crisply crystalline form . The crystals of picric acid first appear as rhombic plates which then lengthen into elongated flat hexagonal blades which can reach 40 mm in length by 2 mm wide in thirty minutes . The crystals are thin and brittle and fragile , and settle to a layer which forms an acicular mass of porcupine like blades growing in all directions . The open structure will occupy a third the volume of the aqueous supernatant solution after slow cooling undisturbed of a boiling saturated solution . The action of a stirbar will break up the crystals into a freely pourable form , and a tinkling sound will be made by the breakup of the crystals as if one was stirring a jar full of thin glass fragments from broken cover slips or slivers of glass from shattered Christmas tree ornaments . If the stirring is continued for too long , the broken up crystals will actually be wet milled into a fluffy and low density powder , so to obtain a good bulk density the disturbing and breakage of the crystals must be carefully watched and limited in extent , and stopped when the desired aggregate density for the material is reached .

Quote:

Wouldn't they be more sensitive, due to breakage when moving and packing them?


That's the whole idea , but there is no danger of initiation of picric acid from anything less than a hammer blow like impact . Normal handling of picric acid will not generate sufficient impact to initiate it accidentally . Like TNT , picric acid is a very safe explosive and very difficult to detonate unintentionally .

Quote:

Also, during boiling down for the second batch, it seems some picric acid is evaporating along with the water, as a cool surface above the boiling liquid accumulates a yellowish condensate from just the steam, without there being any spray (even if I remove from the heat so boiling stops).


Picric acid has a very slight volatility at elevated temperatures . More than likely
the carryover you have observed is due to microscopic particles of the solution , than from actual vapors of picric acid , but in either case it would be only a few milligrams , escaping from even boiling away several liters of solution . The intensity of the dye effect is such that even the smallest particle will cause a tint to be observable wherever it lands on a moist surface .

Quote:

In regards to storage, is alcohol as effective a desensitizer as water? I ask as it's much faster to dry alcohol.


I am not certain , but I doubt it . The water relates to reducing flammability also , which of course alcohol would do just the opposite , and for that reason would seem not to offer any advantage ,
probably being counterproductive in terms of overall safety .

In my own opinion it is unnecessary to store picric acid wet with 20% water .
This was probably something developed as a recommendation for the safer shipment of the material , since the forces generated by transportation accidents are much higher than any forces generated by dropping a bottle onto the floor . Now when it comes to
" accidentally " tossing a jar out a fourth story window , maybe 20% moisture would be a wise precaution :D But for ordinary handling , picric acid is not likely to be any significant danger in any usual scenario . Nothing however is ever completely idiot proof :D

So this is one of those matters where it is a matter of discerning , personal discretion and situational awareness .
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[*] posted on 14-10-2005 at 07:24


Quote:
Originally posted by Rosco Bodine[
Purity , and identification , ease of filtration and drying , bulk density , and sensitivity to initiation are all favored by production of the picric acid in a very pure and crisply crystalline form . The crystals of picric acid first appear as rhombic plates which then lengthen into elongated flat hexagonal blades which can reach 40 mm in length by 2 mm wide in thirty minutes . The crystals are thin and brittle and fragile , and settle to a layer which forms an acicular mass of porcupine like blades growing in all directions . The open structure will occupy a third the volume of the aqueous supernatant solution after slow cooling undisturbed of a boiling saturated solution . The action of a stirbar will break up the crystals into a freely pourable form , and a tinkling sound will be made by the breakup of the crystals as if one was stirring a jar full of thin glass fragments from broken cover slips or slivers of glass from shattered Christmas tree ornaments . If the stirring is continued for too long , the broken up crystals will actually be wet milled into a fluffy and low density powder , so to obtain a good bulk density the disturbing and breakage of the crystals must be carefully watched and limited in extent , and stopped when the desired aggregate density for the material is reached .


When I first noticed the actual vibration of crystals within the flask; it's amazing. I realized that an enourmous format of crystal forms could be developed with PA. And I think one of the major authors mentioned that there was a sensitivity element dicovered during WWI in this regard: an alteration of crystal shape and sensitivity. I posted a little picture of a asprin-PA synth in another thread wherein there is a fairly clear shot of the rhombic plates (one needs to enlarge the photograph, in a browser it doesn't look as good as it could). They almost appear as mica and reflect intensly. At first glance they do look like tiny pieces of broken glass. I have heard and read differing views on the subject of temperature's influence on crystal growth and size. Does anyone have any experience with nitrated phenols in that regard?
[Generalized concept, that of lead azide being too sensitive in a needle crystal format & thus the use of cold water during a synth and dextrine]




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[*] posted on 14-10-2005 at 18:27


From everything which I have observed in my own experiments with picric acid crystallizations , the two factors which are consistently critical to the formation of excellent crystals are high purity of the crude product and significant batch size or
provisions to reduce the cooling rate of
smaller batches .

The thermal mass of batches at half mole scale or larger is required for good crystal formation , due to the slowed radiational cooling of reaction vessels . If work with smaller batches is being conducted , then insulation must be wrapped around the hot solutions of picric acid , in order to slow the heat loss and enable the formation and growth of good crystals .

Recently I have performed a repetition of my own previously developed and described synthesis for picric acid which has always produced a very pure product from purified aspirin , using for each 1 gram of ASA , 4 ml of 92% H2SO4 , and 1.8 grams of NaNO3 . Typically the synthesis total yields are about 90% of the theoretical , of recrystallized picric acid , based on ASA .

My most recent synthesis was done on a slightly more than 1 mole scale , 1.04 moles of ASA used as the precursor . The crude picric acid obtained after a 5 hour nitration procedure and then a 1.5 hour dilution and cooling , was *very* light in color and the diluted reaction mixture was so pale in color and free from any dark colored impurity that upon filtration it did not even stain the filter paper yellow ! This is the first time I have ever seen this occur .

The crystals direct from the diluted nitration mixture were very uniform hard gritty fine mesh material which had the free draining easily filtering physical consistency of fine quartz beach sand found in the surf line . It is the sort of material which is semi-fluidized by a small amount of water to form a mobile slurry , which behaves as a liquid suspension for a few seconds following agitation , but then settles quickly to a dense mass from which the water rapidly drains .

The crude picric acid after filtering , required 5200 ml of boiling distilled water for its dissolution . The solution was performed in a 6000 ml Erlenmeyer flask resting upon a 12" square Cimarec hotplate stirrer . Upon cooling overnight to ambient temperature the excellent crystals were filtered and dried , 198 grams of extremely pure picric acid obtained from the first recrystallization , 83% of theoretical based on ASA . The color and crystal appearance is consistent with that of the finest reagent grade obtainable from pharmaceutical manufacturers .

The bulk density of the loosely poured untamped crystals is 0.7 .

The five liters of filtered solution from the first crystallization was boiled down to 1300 ml , and allowed to cool for a second crop of crystals . No color change was noted , not a trace of orange nor any precipitation of impurity occurred during this reduction of the original 5200 ml of solution to one fourth its volume for the second crop of crystals , which are identical in color to the first crystals . The physical form is inferior for the second crop of crystals which are fine needles , a felt like mat of fine soft crystals , which are more typical for smaller volumes of hot solution which cool too rapidly to permit the growth of the larger and more dense crystals . 16 grams obtained from the second crop of crystals .

Just for the purpose of seeing what might precipitate , the filtered 1300 ml of solution was boiled down to 300 ml for a third crop of crystals . There was still no color change nor precipitate of impurity , even at this extreme of concentration to a small residue of the original volume of the solution , and it appears there may be one or two grams at most of powder form precipitate of picric acid as the third crop ,
and the very pale yellow color is unchanged from that of the original solution which has been reduced to one seventeenth , 5.7% of its original volume ......so it was most definitely a very " clean " nitration producing a very pure product directly from nitration of the sulfonated ASA . Total yields are right on the predictable 90% based on ASA from
" Rosco's Good Old Country Recipe for Picric Acid " , and I don't ever complain because the purity is always so excellent and the reaction so predictable . But every time I wonder , where is my other 10% ? :D

It seems like there is just some invisible
" wall " for the reaction efficiency , where the invisible little " loss gremlins " always
get their damn 10% ;)

Anybody else get this problem with picric acid , where it seems 10% simply vanishes into space with no explanation ?

During the course of the sulfonation and nitration , the physical observations indicated that the conversion was occurring to a high degree of completion and as I watched the reactions , it appeared to me that the process is very close to a quantitaive conversion having no observable indication of byproducts or loss . Yet no matter how clean or complete the reactions appear while in progress , and no matter how consistent the form and color of the end product , 90% yield by the numbers * always * seems to be the result . So what I am beginning to wonder seriously is if the mole weight of aspirin given in the literature as 180.16 is correct , or if aspirin is actually a hydrate having 10% greater mole weight . But the ASA which I use is recrystallized from alcohol , so it would seem likely that if there is a hydrate of aspirin , then it is molecular water , and not merely water of crystallization . The same thing could apply to resorcinol , where it seems a
similar yield limitation is observed for
conversion to the nitrated derivative .
If the mole weights being used for calculation are not on the mark for the actual precursor being used , then the discrepancy would be explained for how a reaction which looks like it is quantitative , never seems to add up that way when running the final numbers .

I really hate to question the numbers provided by authoritative sources in the literature , but when my experiments continue to point to such a possible discrepancy regarding molecular weights ,
the implication is inescapable that the numbers given in the literature just could be in error .

I suppose simple titration of a sample of ASA using a good color indicator would be a good place to start trying to see if the published mole weight of 180.16 seems correct or not .

[Edited on 15-10-2005 by Rosco Bodine]
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[*] posted on 15-10-2005 at 06:51


I am making an assumption that your synthesis is not done in a sealed situation.....Perhaps it is that we are not operating in a vacume & that is a possible explanation for the "missing 10%" ?
Do not large chemical plants use most every production operation (especially nitrations) in a vacume for environmental reasons as well as reactive ones...?




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[*] posted on 15-10-2005 at 07:07


At one time I thought that possibly there was initial loss from volatility during sulfonation of the ASA , but have ruled that out by doing the sulfonation in a loosely glass stoppered flask . I have good ground jointed glassware and I would notice anything obvious in the way of a side reaction . I study and monitor reactions very carefully and make time and temperature notes , keep log sheets of timed observations and notes of any changes that attract attention .

For example :

I just recently in this last experiment have pegged the fact that nitrosylsulfuric acid is present in the nitration mixture and accounts for the red fumes which appear when the finished nitration mixture is diluted . Nowhere have I ever seen this reported , but I'll guarantee you that what I am observing is a fact .
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[*] posted on 16-10-2005 at 12:38


Quote:
Originally posted by Rosco Bodine

I just recently in this last experiment have pegged the fact that nitrosylsulfuric acid is present in the nitration mixture and accounts for the red fumes which appear when the finished nitration mixture is diluted . Nowhere have I ever seen this reported , but I'll guarantee you that what I am observing is a fact .

This is interesting stuff......
Indeed; often I miss items that SHOULD be noted (as the above) because I believe that such a thing is not an anomly. Principally because I have nothing to compare it to. If I were to have a classic example of this or that nitration (visually, etc) , I could note a unique issue. {I don't mean to harp on the "visual" thing, it's just an example} however.... I too have had this (red fumes arise during dilution). phenominon. The finished product in that instance (it was some weeks back) lacked the purity I had gotten previously. What issues contribute to nitrosylsulfuric acids' creation at that point in the synthisis? Or is that a moot point and other factors over-ride the existence of nitrosylsulfuric acid? - As I have seen this with other nitrations as well.




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[*] posted on 16-10-2005 at 12:43


That's interesting. The only reddish fumes I've noticed are when squirting water from the wash bottle into the foam during late nitration. I was under the impression they were just NO2 trapped by the foam being released when the water broke through it.



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[*] posted on 16-10-2005 at 15:33


The first mention of this was made in the earlier post where I attached the file for the page from Urbanski describing the nitration activity series for common nitrates .

My most recent nitration was one where I refined some temperatures , reaction rates and holding times by a very gradual adjustment of the conditions which I have always generally followed with good success . The nitration went more smoothly and produced a more pure product than any picric acid from ASA synthesis I have ever done , and absolutely no red fumes were produced from the beginning to the completion of the nitration , when most of the picric acid had already precipitated as fine crystals in the spent acid mixture .

Only after the nitration was completed and cooled somewhat , when the mixture was being diluted for the precipitation of any not yet precipitated product dissolved in the spent acid mixture , did red fumes suddenly appear during that stage commonly called the quenching or drowning of the spent nitration mixture .

It was very evident that water was the trigger for the evolution of the red fumes ,
the mixture boiling on contact with the stream from a wash bottle , as the dilution was cautiously performed by sheeting the water down the inner walls of the flask . There was a fair amount of the red fumes evolved when the mixture was diluted , and I have seen the same thing occur when spent nitration mixtures are dumped over ice , so it is indeed the water and not the temperature which is causing the hydrolysis . The diluted nitration mixture smells strongly of nitrous acid and I believe some of the acid is also trapped in the crude crystals , which accounts for more water being required than should be required for the dissolution of the crude picric acid . The presence of the residual acidity lowers the solubility of the crude product below what would be the solubility of the pure picric acid after being freed from the nitrous acid impurity .

I believe that nitrosylsulfuric acid is an unavoidable component of the nitration mixture when it is a low water content mixture using solid nitrate and sulfuric acid . It is accumulating in the nitration mixture over the course of the nitration ,
and it may even be essential to the nitration . Knowing it is there helps in avoiding the conditions for its decomposition in an uncontrolled fashion
which could cause a late nitration stage runaway .

There are different strategies which could be applied to exploit the usefulness of the nitrosylsulfuric acid * if * it is found to be a desirable component in the nitration process , perhaps such as using an added nitrite as well as the nitrate , in some combination of proportions or sequence . Or on the other hand if the nitrosylsulfuric acid proves to be an undesirable byproduct , then there are some combinations of temperature and water content which would tend to cause decomposition of the material and limit its formation .

Which of these findings or strategies has validity is too early for me to know , and would require further experiments . This is likely " old news " and is another aspect of the " lost art " specifics which were probably once common knowledge about picric acid , in the long lost details of manufacture done a hundred years ago .
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[*] posted on 17-10-2005 at 06:22


Quote:
Originally posted by Rosco Bodine
There are different strategies which could be applied to exploit the usefulness of the nitrosylsulfuric acid * if * it is found to be a desirable component in the nitration process , perhaps such as using an added nitrite as well as the nitrate , in some combination of proportions or sequence . Or on the other hand if the nitrosylsulfuric acid proves to be an undesirable byproduct , then there are some combinations of temperature and water content which would tend to cause decomposition of the material and limit its formation .

Which of these findings or strategies has validity is too early for me to know , and would require further experiments . This is likely " old news " and is another aspect of the " lost art " specifics which were probably once common knowledge about picric acid , in the long lost details of manufacture done a hundred years ago .


The length and legibility of my notes needs to increase many fold as this question is something I am familiar with but did not have enough noted down at the time of the experiment. First off, I have seen this phenominon in the ice quencing of distilled 90+ % HNO3, however at the time I thought nothing of it. The yield was high albiet less pure than previous. But here this leads me to a speciific question of terminology. When the expression "run-a-way" is used in a nitration we assume that to mean an uncontrolable reaction. Is it possable that a run-a-way reaction may occur that simply results in oxcidation of the product to a greater or lesser extent and does not threaten a catostophic end result?
Where I am going with this is; could a run-a-way occur on a tiny scale, yielding inconsistent results, etc?




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[*] posted on 17-10-2005 at 06:53


Some nitrosylsulfuric acid is even produced in the mixture of nitrate and sulfuric acid from which nitric aicd is distilled , and it can be seen decomposing when water is added to rinse the residue from the flask , producing a roiling cloud of NO2 from the decomposition of the nitrosylsulfuric acid when the water contacts the material . The origin of the material is from the natural decomposition of some of the nitric acid , and this decomposition is catalyzed by direct sunlight . Sunlight by itself can cause an
autocatalytic decomposition runaway oxidation to initiate in a nitration mixture .

Direct sunlight is your friend if you are intending to get a fulminate sort of reaction going . But that is not what you want to see in a nitration mixture , so direct sunlight should be avoided .
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[*] posted on 17-10-2005 at 15:37


Regarding red fumes appearing during distillation, I have a question. I have not observed the evolving of fumes when water is added, but when I notice orange fumes appearing during VACUUM distillation (which seems to me must mean I've heated too fast), if I momentarily let air in, the fumes disappear. At first I thought the inrush of air was simply pushing the NO2 back to the boiling flask, but on a closer look they actually become white/clear. Now, I can't think of what in air would change the NO2 to something else.



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[*] posted on 17-10-2005 at 18:59


2 HOH + O2 + 4 NO2 -----> 4 HNO3

Airborne water vapor and oxygen is the clarifier .

Nitric acid is found in rainwater after
thunderstorms .
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[*] posted on 18-10-2005 at 05:57


Quote:
Originally posted by quicksilver
On another note I have used a process wherein picric acid is prepared by nitration of a nitrosophenol intermediate by preparing the phenol with sodium hydroxide and sodium NITRITE. The resulting nitrosophenol intermediate is then nitrated by a standard nitration process using strong HNO3 - and in this instance methlene chloride / HNO3 may not be exposed to much heat. Or a H2SO4 / solid nitrate mix may work. In any instance it is ment to be processed a much lower temp.
Unfortunatly it comes from a UK patent application (#365, 208 David Salter, 1973) so I am having trouble getting a PDF file....:(



The patent you mentioned is GB1278576
describing the conversion of phenols to a nitrosophenol intermediate , and then nitrating to produce the normal nitro compound .

I tried to upload the file , but it is over
1 MB and the server won't allow the upload saying the file is too large .

I thought we had some bandwidth now ,
so what's up with that stuff ?
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[*] posted on 18-10-2005 at 06:28


Quote:
Originally posted by Rosco Bodine
The patent you mentioned is GB1278576
describing the conversion of phenols to a nitrosophenol intermediate , and then nitrating to produce the normal nitro compound .

I tried to upload the file , but it is over
1 MB and the server won't allow the upload saying the file is too large .

I thought we had some bandwidth now ,
so what's up with that stuff ?


Thank you for hasseling that.
I want to know how you can actually get the whole thing from Espacenet......I have a terrible time with that site.
Now, the reason I was so damn off on that patent number is that it came from THE PREPRETORY MANUAL OF EXPLOSIVES, which, in another thread I continually blast for being inaccurate. Almost EVERY DAMN patent # is wrong. Some off by one number, some wildly off like this one. The synth was fine so I kept it in my notebook but the number was -=no where=- close or related. I just remembered when I read your post. --- Wow that book is so full of typos and inaccuracys, I can't tell you all of them. I'll even bet that some of the stuff is dangerously mis-directed. I always double check things from there with someone else or try to find the patent .
Thanks for trying however, I really enjoy the stuff you find and make good use of it.:D




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[*] posted on 18-10-2005 at 07:13


That " manual " is a complete fraud based on my impression of excerpts mentioned by others who reference it ....another crap book of misinformation written by some asshole who doesn't know WTF he is talking about , but pretends that he does , just to make a buck , while endangering the lives of anyone who trusts the information .... a real slimy kind of lowlife is what such authors are :D

I'll give away better information for free , and accurately provide references and explanations as best I can , along with some unpublished stuff of my own invention as a bonus ...all for free :D

You just can't beat the price folks !

Maybe I should write an e-book and call it
Rosco's Good Old Country Recipes for Pyros , with patent references and lab notes .....guaranteed penis enlargement / mind expanding formulas which even dullard dickheads can follow and see results in only thirty days ! Oh God , she blinded me with SCIENCE ! :D:o:cool:

Hmmm.....about ESPACENET , the wrapper for the pdf's has to be handled in an awkward way in order to recompile a standard pdf . First you have to reset the document security setting for each saved page to " no security " , close and save changes . Reopen each page and delete the " ghost pages " which contain no images so that each page is an image that is only " page 1 of 1 " instead of
" page whatever of some other number of total pages " , by deleting any preceding or following " ghost pages " which contain no images . Close and save changes to each page . Now you should have security removed from actual single page saved files , and rename the files according to their actual page numbers ,
for example ,
GB####### ( decriptive title ) ,
GB####### ( page 2 ) ,
and so on ......

Then insert the pages one at a time to the document first page , in the correct sequence , advancing the page view to each new page just saved , and when the final page is added and viewed , close the assembled document and save changes . Simple huh ? :D
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Rosco Bodine
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biggrin.gif posted on 18-10-2005 at 08:04
She Blinded Me With SCIENCE


A real classic ........

Romy And Michele's High School Reunion: More Music Soundtrack Lyrics

--------------------------------------------------------------------------------

Artist: Thomas Dolby

( Lyrics ) Song :
She Blinded Me With Science .......


It's poetry in motion
She turned her tender eyes to me
As deep as any ocean
As sweet as any harmony
Mmm - but she blinded me with science
"She blinded me with science!"
And failed me in biology

When I'm dancing close to her
"Blinding me with science - science!"
I can smell the chemicals
"Blinding me with science - science!"
"Science!"
"Science!"

Mmm - but it's poetry in motion
And when she turned her eyes to me
As deep as any ocean
As sweet as any harmony
Mmm - but she blinded me with science
And failed me in geometry

When she's dancing next to me
"Blinding me with science - science!"
"Science!"
I can hear machinery
"Blinding me with science - science!"
"Science!"

It's poetry in motion
And now she's making love to me
The spheres are in commotion
The elements in harmony
She blinded me with science
"She blinded me with science!"
And hit me with technology

"Good heavens Miss Sakamoto - you're beautiful!"
I -I don't believe it!
There she goes again!
She's tidied up, and I can't find anything!
All my tubes and wires
And careful notes
And antiquated notions

But! - it's poetry in motion
And when she turned her eyes to me
As deep as any ocean
As sweet as any harmony
Mmm - but she blinded me with science
"She blinded me with - with science!"
She blinded me with

Attachment: blinded.mid (27kB)
This file has been downloaded 1138 times

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Sickman
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[*] posted on 18-10-2005 at 22:07


Right on with Quicksilver; Rosco Bodine's posts are priceless. Also dido with the Preperatory Manual of Explosives. If I'm not mistaken Rosco warned me about that book years ago.

He is right, it's a crap book. When I read through the pages I feel like the author is victimizing all of his customers by not telling them upfront where he got the info and that it's not been tested by him and how dangerous it may be based on that fact.

As far as ESpnet is concerned I use it along with other search engines, but when I find a US patent I want, I go to Patent Fetcher cause it's just a quick and free PDF download.

[Edited on 19-10-2005 by Sickman]
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quicksilver
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[*] posted on 19-10-2005 at 06:45


Quote:
Originally posted by Sickman

As far as ESpnet is concerned I use it along with other search engines, but when I find a US patent I want, I go to Patent Fetcher cause it's just a quick and free PDF download.

[Edited on 19-10-2005 by Sickman]



Good call...seems like a winner.;)




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quicksilver
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[*] posted on 19-10-2005 at 07:35


Quote:
Originally posted by Rosco Bodine
That " manual " is a complete fraud based on my impression of excerpts mentioned by others who reference it ....another crap book of misinformation written by some asshole who doesn't know WTF he is talking about , but pretends that he does , just to make a buck , while endangering the lives of anyone who trusts the information .... a real slimy kind of lowlife is what such authors are :D

I'll give away better information for free , and accurately provide references and explanations as best I can , along with some unpublished stuff of my own invention as a bonus ...all for free :D

You just can't beat the price folks !

Maybe I should write an e-book and call it
Rosco's Good Old Country Recipes for Pyros , with patent references and lab notes .....guaranteed penis enlargement / mind expanding formulas which even dullard dickheads can follow and see results in only thirty days ! Oh God , she blinded me with SCIENCE ! :D:o:cool:
:D



GOD....You can't see how much I am smiling because that song IS my little quirk song.....it buzzes in my head when I start getting nuts with all sorts of crazy crap around my house. My wife thinks I have "unique hobbies" and asks that I never share my interests with our friends (Like I am going to discuss acid distilltion with an asst. American History prof. who always calls her classes "HER-STORY";).
You know that Lagard has published some very seriously dangerious garbage. The other one I remember (but did not buy, of course) was some crap about chem-weapons! No BS! The guy had stuff in there about seriously deadly poisons (real WMDs). And undoubtly he documented them as well as he did his work on energetics. That is a time-bomb waiting to have some tragic repercussions. The whole thing with him that really ticked me off is that one needs to actually have the book in one's possession to find the discrepencies, the typos, and the omissions. Thus paying money for the privlege of frustration and annoyance. The damnist thing about it is that it doesn't seem like a crap book from a casual glance. That's the nastiest thing. - Confession time... - I actually bought it when it first came out.

No bullshit stroke here but you DO have some strong background and commumication skills. That is what leads to success in both writting and teaching. ---- Lord knows you know your shit. But you can communicate. THAT, is a rare thing. I know a bunch of folks with Grad and Post-grad backgrounds that can't communicate. Maybe you -should- write.
- - And actually I don't mean some "explosives_book" ( you could actually write an "explainitory-explosives" book detailing all the pitfalls of other authors; that would be a help; as well as entertaining)......I mean a money maker like a high school chemistry book that pulls kids in. That makes them not only understand but enjoy reading & practicing chemistry. A "Tutor text", not a text book per se'. We know that all the lab shit that was done when I went to school (70's) can't be done now, so a lot of kids find chem dull. If you could find stuff that intregues them using examples that would get past a school board you could pull down about a hundred grand for essentially writting a thesis if the publisher pushes the book to a big school system.
Hell when I was in high school we had a teacher that blew crap up in class and no one thought a thing about it. He grew crystals (all sorts of toxic stuff) and was a great communicator. And even jocks past his class because it was fun. Or you COULD do some antithisis-of-the-explosives book genre'.....it would certainly sell as much as Lagard's stuff after folks find all the holes in the work.
Anyway, my Email is on the board, if you EVER want to bounce an idea around I would be very happy to check out what you're cookin' up.

[Edited on 19-10-2005 by quicksilver]




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Rosco Bodine
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[*] posted on 19-10-2005 at 08:32
picric acid from ASA , NaNO3 and 92% H2SO4


The most recent synthesis is one where some temperatures were closely watched and refined , and the nitration went very smoothly with absolutely no surging nor red fume production , resulting in an exceptionally pure end product in 90% yield based on ASA . So the conditions are a good baseline reference for any fine tuning of the process in efforts to get a little better efficiency . I believe it may be ultimately possible to get yields up around 98% using some adjustments , but a 90% yield process provides a good place to start .

The synthesis followed my rule of thumb proportions which have always produced a good result , for each 1 gram purified ASA , 4 ml 92% H2SO4 , 1.8 grams purified NaNO3 .

In a 1 liter Erlenmeyer 24/40 flask was placed a 10 X 35 mm stirbar and 750 ml of
92% H2SO4 heated with stirring to 80 C .
187.5 grams of purified ASA was added in small portions as fast as it would dissolve in the stirred mixture over the course of 45 minutes , the temperature gradually rising to about 105 C by the heat of reaction as the ASA dissolved . The flask was loosely stoppered with a hollow glass 24/40 stopper . Supplemental heating gradually raised the temperature to 118 C at the end of 90 minutes and the heating was discontinued . After standing overnight the sulfonated ASA mixture had cooled and solidified to a dark colored transparent gel filled with small tan cubical? crystals of sulfonated ASA . The mixture had to be reheated to 115 C to melt and with stirring redissolve so the mixture could be poured into the nitration flask .

Into a 4,000 ml Erlenmeyer flask was placed a heavy ( 62 gram ) 3 inch oval stirbar , and was set upon an old Type 1000 Thermolyne 7.5 X 7.5 stirrer hotplate . Dry , sifted free of lumps , NaNO3 , 339 grams total was divided into three equal 113 gram portions in preparation for the nitration and kept in sealed containers .

The hot sulfonated ASA mixture was poured into the 4L Erlenmeyer , the 900 ml of hot liquid not quite deep enough to completely cover the stirbar . An 18 inch thermometer , 260 C 75 mm immersion , was leaned diagonally in the flask with its tip sitting in the curved bottom outer edge inside the flask . A 4 inch flexible ventilation duct mounted in an extension ring was positioned next to the flask opening for removal of any fumes by the
remotely located blower whose intake air is drawn through the 4 inch hose and discharged outdoors . A second larger fan was situated next to the low workbench to pull a gentle draft in the same general direction as the higher velocity intake adjacent the opening of the flask . These sorts of precautions are essential for safely conducting a nitration on a molar scale . The nitration was conducted outdoors in an area shaded from direct sunlight .

The stirrer was started and run just below the speed where splashing of the shallow liquid occurred , with portions of nitrate begun with the mixture at 95 C ,
the decarboxylation foaming occurring instantly on contact from the first addition of nitrate . The additions were made steadily in portions using a teaspoon ,
adding the nitrate in heavy sprinkles into the vortex , the reaction temperature rising and maintained in the range of 100 to 103 C by regulating the rate of additions of the solid nitrate . The effervescence of CO2 from decarboxylation
occurred freely with no persistent foaming through the end of the addition of the first of the three portions of nitrate , and midway into the second portion at 1 hour from the beginning of the nitration . At this midpoint , the effervescence becomes more sluggish and the viscosity of the mixture is increased , the foaming from decarboxylation causes a volume increase for the mixture , and the additions must be slowed considerably . At the end of the addition of the second portion , the heat of reaction alone is insufficient and very gentle supplemental heating is added to maintain 103 C . About 15 grams into the final portion of nitrate , the time from the beginning of nitration will be 1 hour 45 minutes and some picric acid will begin to precipitate in the thickening mixture , greatly slowing the remaining additions . The stirring speed is increased and the heating is raised to 106 C by 2 hours from the beginning of nitration . The remaining nitrate additions go very slowly and will require as much time as all of the nitrate previously added . The temperature is very gradually allowed to increase over the remaining additions of nitrate , the following observations were made for
reference concerning the elapsed times from the beginning of nitration , and the total amount of the third portion of nitrate having been added .
@ 2 hours 15 minutes , 30 grams ,
107-108 C
@ 2 hours 30 minutes , 40 grams ,
109 C
@ 2 hours 45 minutes , 45 grams ,
111 C
@ 3 hours , 55 grams , 113-114 C
@ 3 hours 10 minutes , 60 grams , 114 C

At this point the mixture has become a very thick slurry and additions are suspended for a time . There is an accumulation of solids upon the walls of the flask and the thermometer is used to scrape the material into the vortex so the mixing can be accomplished . This manual assistance is required several times during the course of the remaining nitration . Close temperature control is essential to limit temperature to 114 C , as there are indications of an induction point for decomposition at about 116 C .

@ 3 hours 30 minutes , nitrate additions cautiously resumed , 113 C reaction temperature
@ 3 hours 45 minutes , 70 grams , 112 C
@ 4 hours , 85 grams , 112 C
@ 4 hours 30 minutes , 113 grams completion of addition 110 C , Supplemental heating very slightly reduced , reaction allowed to continue
@ 5 hours , slowly finishing reaction has cooled to 100 C and reaction appears complete , the temperature is subsiding
and the mixture is thinning as the temperature falls . Supplemental heating discontinued completely .
@ 5 hours 10 minutes , 97 C , mixture is now much thinner and is a free stirring smooth slurry with no foam whatsoever ,
a suspension of fine yellow reflective crystals of picric aicd suspended in a water clear colorless supernatant liquid of spent acid and bisulfate in solution
@ 5 hours 20 minutes , 92 C , cautious and gradual dilution of the stirred mixture was begun by streaming water from a wash bottle onto the inner walls of the flask and allowing the stirred mixture to be gradually diluted , limiting the temperature rise to 100 C , a total of about 1 liter of water was added . The dilution was accompanied by a fair amount of red fumes being evolved , believed to be the result of decomposition of nitrosylsulfuric aicd present in the spent nitration mixture .

The total volume of the diluted mixture was at the 2,000 ml graduation on the flask .

@ 6 hours , 74 C , ice is added to bring volume of diluted mixture to 2800 ml ,
and to speed cooling .

@ 6 hours 15 minutes , 23 C

Flask is placed in refrigerator to complete the precipitation .

The crude picric acid is filtered and blottered , and the still damp crystals are redissolved in 5200 ml boiling distilled water . On slow cooling , excellent crystals are formed , which after filtering and drying , are obtained 198 grams from the first crystallization , 83% yield based upon ASA , of exceptional quality picric acid .

An additional second crop of crystals ,
16 grams is obtained by boiling down the filtered liquid from the first crystallization to a volume of 1300 ml , and allowing to cool .

Yet a third crop of maybe 2 grams can be obtained by concentrating to 300 ml and cooling .

There was absolutely no dark colored impurity produced to tint the solutions or to precipitate and contaminate the product . The picric acid produced was
absolutely free from any contamination byproducts .
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ordenblitz
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[*] posted on 19-10-2005 at 09:36


Thank you very much...

I was wondering when you were going to post:

Rosco's Good Old Country Recipe for TNP
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[*] posted on 19-10-2005 at 10:33


@ordenblitz

You are very welcome , as is everyone
who has also been interested in PA from ASA by way of the modern variation on the ancient process using NaNO3 and the
sulfonation mixture .

It's overdue that I paid close attention to the temps and times and set forth the details for a clean nitration . I will probably experiment further in refining the process . The possibility of increasing the amount of H2SO4 by 10% or so may
have merit for yields and safety . This
process which I have worked out is still very much EXPERIMENTAL , even though it has produced the results I have described , it is possible the reaction may not * always * follow exactly the same course every time for me or for others .

I will emphasize that those temps are already " pushing " the reaction to cut down on the time requirement , and are
not far below safe limits , but at the same time are about right for what is needed to get the job done . Sorry there's not more headroom allowed for getting sloppy with the additions , but such is the reality for the thermodynamics of this particular nitration . You need to be familiar with the heating response of your hotplate and not overshoot the mark , because the mixture absolutely won't forgive it ,
and may require the expansion room afforded by a large reaction flask .

A minor error * may * result in a foaming which itself lowers the concentration of the reaction mixture and self regulates the reaction to oppose a potential runaway , so that the reaction subsides on its own and the nitration can be resumed . However , this is not guaranteed and depends on just how
" minor " is the error outside of the window conditions . I am not about to deliberately cause a runaway out of curiosity to explore the parameters of such a scenario , not without remote manipulation and a good solid bunker
from where I can watch what happens on a video monitor :D

There are inherent dangers in all nitrations , but this one appears to be reasonably predictable and safe , if the process is carefully done .
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[*] posted on 20-10-2005 at 06:53


Quote:
Originally posted by Rosco Bodine

There are inherent dangers in all nitrations , but this one appears to be reasonably predictable and safe , if the process is carefully done .


I have not heard much about runaway reactions w/ nitration of phenols, I have heard about it w/ amines and the typical nitric-ester issues. but not with Phenols. I know it's possable w/ any nitration but yet I have heard little spoken of it.
You have been on these boards a long time; have you ever heard about someone having a runaway w/ PA?
The reason I ask is that during the "red-goo" issue I heard many people push the limit with phenol nitrations and the runaway / safety issue was rarely discussed.:o




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