Xylitol Pentanitrate

[me234]

So I came across a small tub of xylitol, and being the business man that I am, parted with half my life's savings to get it.
I then subsequently fell asleep and had the following dream:

To save you the suspense, it failed miserably :( :mad:

~10g xylitol was dissolved in 20ml 55% HNO3. To this was added 10/15g KNO3(crap scale). This was dissolved as far as possible and then cooled to ~0oC.
Calculations performed earlier led me to believe that my dream required me to add 120ml 98% H2SO4 to this solution/mixture (KNO3 didn't fully dissolve).
The H2SO4 was then added a few ml's at a time to the nitrating bath while keeping the temp. below 10oC. After ~60ml a large amount of white precipitate had formed (what appeared to be crystals). After ~90ml H2SO4 in total had been added, the reaction mixture had become incredibly viscous, with large amounts of white ppt. floating around so I figured the reaction had probably gone to completion. If I looked through the side of my glass reaction vessel, I had to hold the thermometer a few cm away from the side I was looking through, or else the ppt. prevented me from seeing it.
Despite the fact that I was meant to add 120ml H2SO4, I stopped at 90ml and crashed to reaction mixture into some ice and water. The huge amount of XPN (xylitol pentanitrate) I was expecting never materialised, and instead I filtered off a small amount of whitish/clear goo which reminded me of fresh sucrose nitrate.

So, dear Forumites, I was just wondering if anyone might help me work out exactly, kinda, you know..
WHAT HAPPENED???!!!:mad:

The way I worked things out was based on Mr. Cool's MHN synth on his page. I worked out to add 120ml of sulphuric so as to form 1 mole of H2SO4.1H2O for every mole H2O from the 55% nitric (to get 100% nitric), to make every mole KNO3 into a mole 100% HNO3, and to make every mole H2O formed from the reaction into H2SO4.1H2O.

I won't mention the obvious mistake I made in the synth I dreamed so that nobody's ideas are biased.

Total H2SO4 addition time was ~2 hours.

Please help me out here guys, I really want this one working, xylitol is the newest health craze and supply should become good in most countries shortly (check health food places and up-market pharmacies).

I guess I'll hope to have this dream again soon. Let you guys know.

Also, should I happen to dream about this again, I'll follow Mr. Cool's synth for MHN without modification.

P.S. Maybe it naturally is a goo like sorbitol hexanitrate, or maybe I formed some partially soluble lower nitrate?

[megalomania]

There are many factors that could have gone wrong in this synth. Perhaps your sulfuric acid decomposed the xylitol, maybe the reaction temperature was not low enough throughout the reaction, it could be your nitric acid strength or nitrate concentration was not high enough, mayhaps your product was still dissolved in something, or the reaction just was not run long enough. Heck, even lack of stirring could have affected your results.

In short there are too many variables for anyone other than yourself to predict the cause short of some obvious use of the wrong reagent. It would help me if you could reprint the MHN procedure as Mr Cool’s website is down for the moment. My own MHN procedure is quite different than what you have described.

[The_Duke]

Maybe it naturally is a goo like sorbitol hexanitrate, or maybe I formed some partially soluble lower nitrate?

Xylitol Pentanitrate is a whitish/clear viscous syrup...

It has very little practical use IMHO.

[me234]

Mega: I don't have it on hand at the moment. Basically it consisted of dissolving the mannitol in a nitric acid mixture made from a bit of 70% HNO3, a fair amount of KNO3 and a small bit of sulphuric to convert the KNO3 to HNO3, cooling to below 0oC, then keeping it that way while you add the rest of the H2SO4.
Not exactly the most conventional way yes, but it has worked before for me. If I don't dream up this way, then I go with the dissolve the poly-hydroxide in HNO3 and add in the H2SO4 while keeping temp. low.

The_Duke: Thanks for the refernce, I could have sworn I'd checked everywhere in the PATR2700, but I'll go look later. I'll definitely dream this one up again, you'll be the second person to know how it went, well, along with the rest of the forum of course he, he. When I find the Federoff stuff I'll probably post a quote for everyone else to read. Thanks again

[quicksilver]

I think this is the one you mean. It comprises the subsitution of mannitol for sorbitol.
In any instance I believe that there are no failed experiments; simply more or differing data. I hope you continue frankly. For instance: most of what was discovered about ETN on this board was produced by people experimenting; there was little material to start with.
I worked with some frustrating experiments but eventually not only did I learn quite a bit but found success in areas that I thought at first to be fruitless. Keep going!
-->Some notes of mine and Mr Cool's stuff as well.
___________________________
4) Sorbitol Hexanitrate

This is very similar to Mannitol Hexanitrate (see below). Shock sensitive, small quantities burn rapidly if ignited. This procedure will produce a sticky liquid product, which is actually a mixture of nitrates. A solid product can be obtained by dissolving it in ethanol, and adding an equal volume of cold water to precipitate it. This will be pure Sorbitol Hexanitrate.

You will need:

5g of sorbitol,
35mL of 70% nitric acid,
70mL of 90% sulphuric acid,
Distilled water,
Sodium bicarbonate,
Urea,
Two 250mL beakers,
A 500mL beaker,
A thermometer,
A hot water bath,
A dropping pipette,
An ice bath.

1) Put the sorbitol and nitric acid in a 250mL beaker, and cool it to 5*C in the ice bath.
2) Stir it until all the sorbitol has dissolved.
3) Slowly add the sulphuric acid, while stirring, making sure that the temperature does not rise above 10*C.
4) After all the sulphuric acid has been added, dump the reaction into the 500mL beaker, containing 200mL of distilled water.
5) Warm the water/acid/product mixture to 40*C to melt the Sorbitol Hexanitrate. It will settle to the bottom.
6) Using the pipette, suck up the prodcut while still warm, and add it to the other 250mL beaker, containing 100mL of water and 10g of sodium bicarbonate.
7) Warm it to 40*C, and stir it for 10 minutes.
8) Add 5g of urea and stir it for a further 10 minutes.
9) Suck up the Sorbitol Hexanitrate with the pipette, and let it dry in a warm place overnight.
-=-=-=
Mannitol Hexanitrate

"This is a different isomer of Sorbitol Hexanitrate, but this one is more widely used, as a base charge in blasting caps. This procedure produces a white powder, and yields seem to be higher. Lead block expansion for this explosive is a whopping 560 cm3, almost as high as Glyceryl Trinitrate! VoD is 7000 m/s, density is 1.60 g/cm3, relative brisance is 0.96 under these conditions.

To make it, use the procedure for Sorbitol Hexanitrate above, but use mannitol instead of sorbitol (duh...), use a mixture of 6mL of 70% nitric acid, 27g of potassium nitrate and 14mL of 98% sulphuric acid instead of the nitric acid, and use 30mL of 98% sulphuric acid. Omit the step in which the Sorbitol Hexanitrate is melted. Simply filter off the Mannitol Hexanitrate and recrystalise it from ethanol after washing and drying the crude product."
------------------------
However I dreamed about this as well and noted that (in my dream, bla, bla) when 20 grams of mannitol was ground very fine (beyond any crystalline make-up via ball mill) was mixed into 130gr (72ml @ 93&) H2SO4 @ 20 C via magnetic stirrer until completely in solution. Material was stirred until transparent. Care was taken to prevent carbonization.
The Mannitol-H2SO4 solution was then placed into a refrigerator to maintain temp of 15 C.
A solid nitrate (KNO3) was mixed with H2SO4 in a separate beaker: 60gr KNO3 into 182 gr (100ml) H2SO4. This was prepared at 60C and stirred until clear solution was achieved. This solution of mixed acids was then placed in a refrigerator and both solutions brought to 15 C.
The mixed acid solution was placed on a magnetic stirring device and into it was introduced the mannitol / H2SO4 solution in small portions (drop wise, 3 drops per second).
The temp of 0-15 C was maintained for this addition & was achieved by using an ice and ethylene glycol ("anti-freeze") bath. During the addition the mixture became quite thick. At that juncture 50 ml of 70& HNO3 was added in two portions. The HNO3 being previously chilled to 15 C having been in a refrigerated environment. The solution continued to thicken and was withdrawn from the ice bath and stirring (total time 30 min, stirring) and placed covered in refrigerator. Allowed solution to remain in refrigerator at 15 C. After 2 hours solution solidified and appeared to have no mobility but appeared as a solid.

The nitration is reputed to proceed unevenly and due to the mass created by the forming crystals within the mixed acids this may certainly be true. That is a significant reason to add the liquid HNO3; to maintain the ability to stir the solution as well as add to the nitration level. Overall the nitration is slow but the initial reaction is such that a thick mass (of crystals) is created quite soon after the introduction of the mannitol / H2SO4. There will be both hexanitrate and pentanitrate within the initial nitration. It has been noted that the appearance of needle crystals as opposed to other shapes is indicative of hexanitrate and this should be the target of production after re-crystallization from alcohol. The re-crystallization if carried out a 2nd time will result in a granular formation which is ideal for utility usage and is not a reflection of pentanitrate formation at that time.

Random observations: After addition of mannitol / H2SO4 there appeared to be particulate matter forming in solution and would stick to side of beaker when tipped. At no time did solution appear clear. As soon as mannitol was introduced into mixed acids there appeared to be particulate matter in solution. NOx gas will evolve @100C after one hour. Solubility: Very sol in hot EtOh, MtOh, Acetone. Best is EtOh Acetone exhibits negative vapor pressure. Stability is achieved by addition of Na Salicylates. Also refer to US Patent 1751438 (Sorbitol Hexanitrate) regarding material's need for temp to maintain above a certain level to maintain solidity, etc.

The various methods of nitration of solid polyhydydroxy alcohols is applicable in a general way to all of those polyhydydroxy alcohols which may dissolve into solution in H2SO4 without decomposition. It is important to note that care need be taken to dissolve into solution and not carbonize these solids. What is meant is that via careful action the above is achieved whenever the polyhydydroxy alcohols are used. Related substances as the aldoses and ketoses. In general H2SO4 of 90-95% is preferred for the dissolving of the solid alcohol but it should be noted that as the strength of the H2SO4 is reduced the yield is diminished. On the other hand if the strength increased the greater chance for carbonization & the overall process is more difficult to control. [Re; US Patent 1660651] Examples of successful nitrations of polyhydydroxy alcohols have been pentaetheriol, etheriol, mannitol, inoslitol, glucose, etc. However their end result nitrated products have varied in sensitivity, VOD, MP, etc from one to another.

Yield: Dealing with totally dry and re-crystallized material starting with 20 grams of mannitol was 18.8 grams MHN. Thus approx .9 grams was produced from one gram of mannitol. Numerically I came out with a 60% - 65% yield on paper but in the beaker I would put it lower. Deceptively large appearing yield at first.
Opinion: Not all that bad if one considers that we are not dealing with distilled acid and I believe that it COULD be improved upon with a higher quantity of HNO3.
There must be a balance between amount of mixed acid and nitrated product. Too much mannitol will give a poorer yield than less than enough. A balanced equation should be stuck to. However if one scales up a synthesis do not believe that simply multiplying all the chemicals will result in an increase in the end nitrated product (in certain cases it may however). In many cases id one is working with a nitration of 1 part polyhydydroxy alcohol to 2 parts H2SO4 and 3 parts HNO3 it may be necessary to alter the acids much more than a simple multiplier of the original starting material weight. Thus if the goal was to nitrate double the original material it may mean that the acids would have to increase more than by a simple dividend of the original.
When using a sulfocation (?) (mixing the nitrated material with H2SO4) make sure that the solution is totally clear and that no material remains floating within the acid. The starting material must be dry, free from impurities and be in a fine particulate form. Often whole crystals of polyhydydroxy alcohols do not nitrate well and need to be reduced to sub-sieve size by crushing, milling, etc. Small particulate matter appears to nitrate more effectively (nitric esters especially). Finished nitrated material should be dumped into an excess of water. A very large amount of water will produce an optimum yield as it will drive the material from it's solvent in re-crystallization, etc. When nitrating polyhydydroxy alcohols never allow lumps to accumulate. This is both a safety & yield issue. If using said nitrates to produce a mixed acid find what nitrate that will produce a clear solution. Some nitrates which are a technical or utility grade (fertilizers) have impurities in them to such a high percentage that they will not mix well or produce by-products. It is a more effective practice to use a nitrate that mixes well than one that in theory will produce a high percentage of HNO3. I don't remember where but an impact test may reviel the presence of (other) that hexanitrates. If the nitrated material does not respond to impact stimulus there may not be hexanitrate. Crudely: if you hammer test the material and you don't get a pop you may not be dealing w/ hexanitrates or a mix, etc. I mention this as some have reported that they have gotten product that does not pop but yet is insoluable in H2O.

However I am very interested that you are dealing with other solid polyhydydroxy alcohols and I am really interested in any future dreams you may have re; this subject.

[Gleng]

You are right, many similar stuff will be suitable for that method but it will not work always and i belive that will have some experience. I`ve picked out some to this.
Adonitol -> Adonitolhexanitrate
Dulcitol -> Dulcitoloctanitrate

[atlas#11]

Wouldn't it be possible to simply slowly add the xylitol to the nitrating mix as was done for erythritol and glycerol? Of course adding an extra couple moles of nitrate.

I can get xylitol in five pound sacks for $11.95 at vitamin cottage (local health food store). I plan on experimenting with this one alot, due to the avalibility, I can get all of the ingredients within a mile of my home. I guess on monday or mabye even tomarrow I'll swing by and grab some and get to work.

Right now I'm taking care of a runaway nitration from a fairly large batch of nirto starch and trying to get it cleaned up before my ride gets here. I think when I get back I'll build a fume hood out of a cardboard box and this squirril cage blower I found in a microwave.

[mil&co]

Yes, adapting the NG synthesis for XPN is possible. SWIM did a batch of about 5 to 10 ml yeild (no graduated cilinder, rough guess), with 60ml HNO3 (68%), 125ml H2SO4 (98%) and 25gr xylitol.

Slowly adding the xylitol, stopping when visible HNO3 vapours appear and good stirring were the keys here. Also powdering the xylitol is highly advisable since clumbs will not dissolve in the nitrating mixture (SWIM will never forget that anymore), leaving you with a crappy yeild (like SWIM's).

After dilluting the acid and letting the XPN sink to the bottom, just decant the water/acid and dissolve the XPN in acetone. Neutralizing in acetone solution will make it more easy since XPN sticks to everything and neutralizing as-is will just give a mess.

After neutralizing, crash the solution with water, and again decant the water and dissolve in (2/3 its volume of) acetone, let the acetone evaporate and you're left with XPN.

XPN is a syrup, looks like NG with water in it but it's somewhat more viscous, and will really stick to anything that comes in contact with it.
XPN boils before burning with a yellow/orange flame leaving a black residue when heated on a piece of Alu-foil. SWIM couldn't get it to detonate with a hammer (XPN soaked in a piece of paper). SWIM does see some potential in XPN as a plastisizer.

[Rbick]

In response to me234's first post: I think your problem with the mixture becoming very viscous lies in the KNO3 and the H2SO4. I have had this same thing happened to me while making NC and NG via the KNO3 nitration method. It ruins the nitration process, and left me with very low quality NC. I noticed it only happens when the temp. with the NC mix rises above 48 C. But I think it is due to contamination, since after I thuroughly cleaned my beakers, I stopped having this problem. Is your H2SO4 and KNO3 good quality? Hope this helps. Good luck.

[mil&co]

SWIM just discovered some interesting properties of a mixture between NG and XPN (XPN:NG 1:9). It deflagrates with a yellow/orange flame, but will boil before doing so much longer than NG will do when not in admixture with XPN (solely NG will deflagrate almost immediately when subjected to heating).
Deflagration of the mixture is more like a "whoush" than the "pffff" you'd expect from NG.

SWIM (low-order) detonated 20ml of XPN/NG (1 to 9 ratio) with a commercial flash-cracker which contained about 2gr of flash.
Mixture was in a cardboard tube and soaked in cotton, cracker was placed inside the centre of the tube. Charge was mostly buried in sand, with the top sticking out a centimeter.

According to SWIM the explosion was loud, nice crater and a fairly impressive fountain of sand.