mannitol = sorbitol ?? - Archive File

[megalomania]

Mr Cool
Frequent Poster
Posts: 991
From: None of your bloody business!
Registered: DEC 2000
posted March 24, 2001 02:09 PM
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I'm posting this, since for a long time I've been wanting some mannitol, for mannitol hexanitrate. Also, for a long time I've been buying sorbitol by the pound for use in rockets. I knew that both were poly-hydric alcohols, but I've never tried to nitrate sorbitol in case it was hyper-sensitive. Just now, I was reading Mega's site, and looked at the structure for MHN. Then, a little later, I was looking at Richard Nakka's model rocketry page, and noticed that if you replace the nitro groups on the MHN molecule, the formula and structure is the same as sorbitol!!!
Is it true that mannitol and sorbitol are synonyms for the same chemical? Please reply if you have any info on this. I don't want to nitrate some sorbitol without making sure that there hasn't been a typo, or maybe one of them got confused.


10fingers
Frequent Poster
Posts: 442
From: USA
Registered: SEP 2000
posted March 24, 2001 02:22 PM
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Mannitol and Sorbitol are two separate things. Hydrogenation of fructose with catalyst will yield a 50/50 mixture of these two sugar alcohols.
Sorbitol can be nitrated to Sorbitol Hexanitrate but I can find no info on its properties.


Mr Cool
Frequent Poster
Posts: 991
From: None of your bloody business!
Registered: DEC 2000
posted March 24, 2001 04:14 PM
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I just found a site on sugar substitutes which mentioned them both seperatley. Oh well, never mind.
If I dare to nitrate some sorbitol I'll post my results.
Oh, and if you want to buy some sorbitol then I've found a place that's easier and cheaper than Skyilghter (I didn't actually search for it myself, Richard Nakka did, but that's not important). It is: www.sugarlessshop.com/2000/sugarsubstitutes.htm It's $3.79/lb, rather than $5.15/lb, and you don't have to give ID or be on file with them. They don't have pure mannitol though.


Mr Cool
Frequent Poster
Posts: 991
From: None of your bloody business!
Registered: DEC 2000
posted March 26, 2001 12:40 PM
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Well, does anyone have any information on hexanitrosorbitol? It'd be very similar to MHN, but I'd like to make sure before I make any, for obvious reasons.

[arm]

I know this is an old thread (revivied+archived by mega) but ive just got to write this in here so that everyone knows. Minnitol and Sorbitol as far as i can remember are structural isomers - they have the same empirical formula but different structural formulas. In other words several key functional groups are in different positions on the different molecules. Mannitols melting point is almost twice that of sorbitol. I would advise caution to anyone trying this for the first time since Hexanitrosorbitols properties are unknown. You have to ask yourself, why isnt it a commercial explosive.

Then i again i could be talking utter bollocks and its completely safe.

[Mr Cool]

Yes, that's right, they are isomers. There is a patent on sorbitol hexanitrate which I will attach. Until just now I hadn't really read the patent very well, since I have quite large amounts of mannitol, therefore I would rather have nitrated mannitol and produced a useful solid explosive directly, without having to use the purification steps to produce a solid form of sorbitol hexanitrate.
But I've just read it and found that the ppted solid sorbitol hexanitrate melts at 52-55*C. Melting point may be lowered by using more water, resulting in more of the lower nitrates being present.
Read the patent. It doesn't have very much information, but we can assume that the explosive will be equal in performance to MHN, but with a melting point of 52-55*C (or lower, if desired), rather than 112*C, thus making casting much easier and safer.

Edit: can't attach .pdf's, so: 1,751,438 (http://www.boomspeed.com/mrcool/sorbitol_hexanitrate.pdf).