4-Stroke - 1-9-2024 at 20:06
EGDN and nitroglycerin are most often made using mixed acids, but can also be prepared using ammonium nitrate and sulfuric acid. I was wondering if
calcium nitrate can be used instead of ammonium nitrate? If it could be,
1. Will the precipitated calcium sulfate hinder the reaction in any way?
2. Will the yield be reduced, and will the reaction time/temperature have to change?
3. Will the reaction be any more unsafe than with mixed acids or ammonium nitrate?
4. Does this work for most other energetic materials (methyl nitrate)?
The molar mass of Ca(NO3)2 * 4 H2O is ~236g
The molar mass of C2H6O2 is ~62g
For every mole of ethylene glycol two moles of NO3 are needed, but I am not sure how much sulfuric acid to use. This is what I have come up
with so far:
-Calcium Nitrate Tetrahydrate - 250g
-Ethylene Glycol - 60g (54ml)
-Sulfuric Acid - 300ml
Maximum Theoretic Yield of EGDN ~ 150g (135ml)
Do you think this could work? How much sulfuric acid should be used?
Thank you.
dettoo456 - 2-9-2024 at 06:49
The Ca(NO3)2 route doesn’t sound implausible, though ammonium nitrate and/or basic HNO3 is preferred because the actual produced NG or EGDN will be
insoluble in water (basic, not acidified), and can simply be decanted off of the reaction mixture. Any product left in the mixture could alternatively
be extracted using Acetone or DCM w/ NaHCO3.
I do not believe the calcium sulfate would drastically hinder the reaction, though keep in mind that uniphase reaction mixtures are almost always more
reactive, unless the heterogenous solid particles can be small enough to either act as reactive sites for reagents or just sink out of the way for the
liquids to react.
Any preparatory method that deviates from the standard developed in industry will more than likely have lower yields. Keeping the temperature low and
the reagents dry, is still very important. Extending the reaction time by 10-15min shouldn’t be an issue though.
The solid particles in the mixture may actually make the whole procedure safer - like with diatomaceous earth + NG in dynamite. But don’t quote me
on that.
This may work for other nitrate esters but not nitroalkanes. It might also cause problems if you attempt electrophillic nitrations.
dettoo456 - 2-9-2024 at 06:55
You will need an excess of H2SO4 as well, to lower the viscosity of the rxn mixture to a stirrable state.
If you have access to DCM (and can recycle it) id just recommend mixing the anhydrous Calcium nitrate (any other dry ionic nitrate) w/ H2SO4,
extracting the sludge with DCM to pull out WFNA, and using that chilled WFNA/DCM solution to directly nitrate ethylene glycol or glycerol. The product
would then be isolated in the DCM and the water layer left nearly acid-free.
[Edited on 2-9-2024 by dettoo456]
FrankRizzo - 28-9-2024 at 11:44
Vacuum distill the WFNA from the calcium sulfate precipitate.