Transesterification and purification of ETN from mixed sulfoesters

Hello everyone, I'm new to the forum, so if I'm asking stupid questions, then tell me, I'll fix it)

To begin with, let me explain what caused this question, you see, I have been doing PETN for quite some time. As you know, one of the methods for its production is nitration with sulfur-nitrogen nitro mixtures in one stage. But at the same time, along with PETN, various mixed sulfoethers are obtained. But they can be removed. To begin with, after adding all the pentaerythritol to the reaction mass, PETN is heated to ~50°C (transesterification reaction), for 20 minutes, thus part of the sulfoesters are converted to PETN, increasing the yield. The other sulfoester (dinitrate disulfate) is removed by boiling the PETN in a Sodium bicarbonate /MgO solution until the foam disappears. Of course, then recrystallization is carried out from acetone with the addition of carbonates to remove the acid inside the crystals.

It should be noted that the transesterification procedure is also carried out for other nitroesters, for example, mannitol is also heated to 50°C for an hour.

And so, I got erythritol. Deciding to first study the practice of its production here, I discovered two things:
1) No one for some reason carries out the transesterification reaction. Hence the low yield of the majority (30-50%) instead of the prescribed ~90%, at least it seems to me In fairness, I found one study where it was heated up to 35°C, but at 35°C interesterification is just beginning, but it goes quite quickly only at 50-60°C. So it's weird...
2) Nobody cleans it from sulfoesters? Why? After all, they affect power, chemical stability.

For me, the question is so acute, because once, due to a highly diluted acid, I received a mixture of PETN: sulfates (50:50). The explosion was weak, the syringe that cut down the tree earlier only tore off the bark (albeit deeply). I'm afraid of getting ETN contaminated with sulfates.

I did not find answers to these questions either on the forum or in research (on the other hand, they were more devoted to mixtures, explosive properties and not synthesis). If this has been discussed somewhere, send me a link, and I will delete this topic so as not to clog the wall

About the synthesis of PETN? Well, I usually get it with a mixture of nitric acid 70% and 94% sulfuric acid (33 ml and 19 ml). or (35 ml and 37 ml if nitric acid 58%) per 10 g of pentaerythritol. These ratios are taken from Urbansky, and are "ideal". That is, any change in these ratios will lead to either a drop in yield, or oxidation, or unnecessary waste of pentaerythritol.

By the way, I did not find similar ratios for ETN. Like the regions of the formation of ETN by nitration mixture Generally speaking, I haven't had any significant problems with PETN. Now I am collecting information about ETN, before its manufacture.

[Edited on 14-7-2023 by DennyDevHE77]

Quote: Originally posted by DennyDevHE77

I am very sorry that my post came out incomprehensible. Perhaps I should have phrased it differently. Let me explain again, using the example of my long work with PETH, I decided that work with other nitroesters (nitromannite, nitroglycerin, ETH) should be similar. That is, the processes of nitration, purification processes, recrystallization, etc. should be similar. That's why I told at the beginning of my post about my work with PETN. I mean, I kind of wanted to say, "Hey guys, I haven't worked with ETH yet, but I've worked with PETH and it's like this, will ETH be the same?"

Quote: Originally posted by OneEyedPyro

Quote: Originally posted by DennyDevHE77   I am very sorry that my post came out incomprehensible. Perhaps I should have phrased it differently. Let me explain again, using the example of my long work with PETH, I decided that work with other nitroesters (nitromannite, nitroglycerin, ETH) should be similar. That is, the processes of nitration, purification processes, recrystallization, etc. should be similar. That's why I told at the beginning of my post about my work with PETN. I mean, I kind of wanted to say, "Hey guys, I haven't worked with ETH yet, but I've worked with PETH and it's like this, will ETH be the same?" The manufacture of ETN is similar to PETN, the purification procedures are also similar. ETN is not as physically or chemically stable as PETN and you cannot treat them interchangeably in synthesis or handling. Refer to the post I left above earlier. If that doesn't answer your question, I'm not sure what will.

I already looked at your post. Unfortunately you were right

In general, I will have to be content with an output of 50-60%. Not very profitable, with a common ratio of 200 g of NH4NO3, 300 ml of sulfuric acid, and 60 g of erythritol. I should get less than 100 g of ETH. After all, the same PETN with 300 ml of sulfuric acid comes out > 300 grams

But the PETN cannot be melted

Although I may be able to raise the yield with acetic anhydride.

For example, dissolve it in 70% nitric acid and warm it. So that it hydrolyzes, and I get a solution of nitric acid in glacial acetic acid with acetic anhydride ...

[Edited on 15-7-2023 by DennyDevHE77]

Quote: Originally posted by DennyDevHE77

heated to ~50°C (transesterification reaction), for 20 minutes, thus part of the sulfoesters

Quote: Originally posted by DennyDevHE77

I received a mixture of PETN: sulfates (50:50).

Quote: Originally posted by Etanol

Quote: Originally posted by DennyDevHE77   heated to ~50°C (transesterification reaction), for 20 minutes, thus part of the sulfoesters This is very very dangerous in the case of ETN! Quote: Originally posted by DennyDevHE77   I received a mixture of PETN: sulfates (50:50). How did you determine the presence of sulfates?

Quote: Originally posted by littlesky

Interesting ideas. In fact, the ester exchange method is very good for synthesizing ETN. This was mentioned in a Chinese literature. They dissolved Erythrose in concentrated sulfuric acid to obtain a pale yellow liquid (possibly the Organosulfate of Erythrose), and then added fuming nitric acid (or a mixture of industrial nitric acid (65-68%)/concentrated sulfuric acid) to this liquid to obtain a high yield (about 87%). A fairly pure product is obtained by removing acid from acetone and sodium carbonate solutions. I have been using this method to synthesize etn since.

Quote: Originally posted by DennyDevHE77

Please tell me your method. I tried to implement the same method just last night. I took 10g of erythritol, and added them to 50g (27g) of sulfuric acid (at room temperature), after 15 minutes, when the erythritol was almost completely dissolved, I poured this solution into 75 ml of 70% nitric acid (extra pure for analysis) with the addition of 30 ml of conc. sulfuric acid. Quite quickly, a white powder began to form inside the reaction mass. I began to heat the mixture in a water bath, at about 55°C the powder dissolved, it seemed as if ETH had decomposed, although some kind of "oil" was visible floating in the reaction mass. I sat down for 15 minutes of heating at 50-52°C, I poured the nitro mixture into 700 ml of ice water. A fine white precipitate fell out, but in a very small amount. 700 ml of water is only slightly cloudy. Perhaps I warmed too little, only 15 minutes, instead of 30-45 minutes. Or I used insufficiently strong nitric acid. [Edited on 16-7-2023 by DennyDevHE77]

Quote: Originally posted by DennyDevHE77

What else could it be but sulfates that were destroyed during the boiling process? PETN can be contaminated, in addition to them, by under-nitrated molecules, BUT, mono- and di-nitrates are soluble in water, trinitrate (PETRIN) is generally liquid [Edited on 16-7-2023 by DennyDevHE77]

Quote: Originally posted by DennyDevHE77

Please tell me your method. I tried to implement the same method just last night. I took 10g of erythritol, and added them to 50g (27g) of sulfuric acid (at room temperature), after 15 minutes, when the erythritol was almost completely dissolved, I poured this solution into 75 ml of 70% nitric acid (extra pure for analysis) with the addition of 30 ml of conc. sulfuric acid. Quite quickly, a white powder began to form inside the reaction mass. I began to heat the mixture in a water bath, at about 55°C the powder dissolved, it seemed as if ETH had decomposed, although some kind of "oil" was visible floating in the reaction mass. I sat down for 15 minutes of heating at 50-52°C, I poured the nitro mixture into 700 ml of ice water. A fine white precipitate fell out, but in a very small amount. 700 ml of water is only slightly cloudy. Perhaps I warmed too little, only 15 minutes, instead of 30-45 minutes. Or I used insufficiently strong nitric acid.

Quote: Originally posted by DennyDevHE77

[rquote=685763&tid=159724& Then I had 70g of PETN left, I made two liters of 1% sodium bicarbonate solution and began to heat PETN in it, when the solution boiled, a huge amount of foam floated to the surface. After an hour and a half of boiling and regular stirring, the foam was gone, I filtered out PETN, and it turned out that 42g of it remained. What else could it be but sulfates that were destroyed during the boiling process? PETN can be contaminated, in addition to them, by under-nitrated molecules, BUT, mono- and di-nitrates are soluble in water, trinitrate (PETRIN) is generally liquid. So besides sulfates, there could hardly be anything. A little later, I suggested that perhaps PETN was simply hydrolyzed during boiling. But then taking 100 g of purified PETN obtained at WFNA, and boiling them for an hour and a half in 2.5 liters of 1% soda solution, I filtered out 98 g of PETN. And maybe I lost them on the filter. [Edited on 16-7-2023 by DennyDevHE77]

Quote: Originally posted by Tsjerk

Quote: Originally posted by DennyDevHE77   What else could it be but sulfates that were destroyed during the boiling process? PETN can be contaminated, in addition to them, by under-nitrated molecules, BUT, mono- and di-nitrates are soluble in water, trinitrate (PETRIN) is generally liquid [Edited on 16-7-2023 by DennyDevHE77] Do you mean to say there can't be under nitrated PE in your PETN because you crashed the PETN in water? I think they are just not that soluble, so they crash out together with the PETN and afterwards when you boil in such a large volume of water they do dissolve. No need for sulfate ester hypothesis, just some not fully nitrated PE. Did you do any cleanup besides crashing the nitration mixture in water or do you just assume that the initial crude product had to be pure and when it wasn't it had to be sulfates?

Quote: Originally posted by DennyDevHE77

What does it mean if I tested the water?

Quote: Originally posted by DennyDevHE77

Please tell me your method. I tried to implement the same method just last night. I took 10g of erythritol, and added them to 50g (27g) of sulfuric acid (at room temperature), after 15 minutes, when the erythritol was almost completely dissolved, I poured this solution into 75 ml of 70% nitric acid (extra pure for analysis) with the addition of 30 ml of conc. sulfuric acid. Quite quickly, a white powder began to form inside the reaction mass. I began to heat the mixture in a water bath, at about 55°C the powder dissolved, it seemed as if ETH had decomposed, although some kind of "oil" was visible floating in the reaction mass. I sat down for 15 minutes of heating at 50-52°C, I poured the nitro mixture into 700 ml of ice water. A fine white precipitate fell out, but in a very small amount. 700 ml of water is only slightly cloudy. Perhaps I warmed too little, only 15 minutes, instead of 30-45 minutes. Or I used insufficiently strong nitric acid.

Quote: Originally posted by PLSHY

I just took a look and found that the uploaded file cannot be opened. This is a word document. Please rename it and check it out!

Yes I did synthesize a batch of etn of the 750 gram grade and guaranteed yield it was truly astounding I even made a file of it which was rather large and not of high quality I just Not going to show it, but I will show a screenshot from the file to prove the truth of what I said, in this screenshot you can see the 1000ml beaker full of etn, this batch is my long time The previously synthesized product is still pure white after being refined with acetone, but I did a comparative test. If it is refined with methanol, it will turn yellow after a week. I originally wanted to use methanol, because acetone is even harder to buy in China than fuming nitric acid, potassium perchlorate, CHZ, mainly because of anti-drug regulations. But in the end I contacted the chemical solvent factory and successfully purchased a barrel (25L) of acetone. So now I am synthesizing according to the method in the literature, which can not only ensure high quality but also ensure the controllability of the reaction. Synthesizing according to the literature is a very wise choice, because not only the yield is very high, the quality is very good, but the reaction is also very easy to control. I tried to synthesize 3kg of PGDN once, and I deeply realized that for large-scale synthesis. How important is the ease of control. In the end, I would like to say that I am very happy to share the literature of Chinese enthusiasts. Science has no borders. It is a very proud thing to share excellent literature. Sadly, the author of this etn synthetic literature is due to mass storage rdx (about 15KG) was sentenced to several years in prison.