paioniotic folds
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Registered: 24-9-2014
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Distillation of Nitromethane from RC fuel
Hello, Im rather new here, so please forgive any stupidity on my part.
I tired to distill nitromethane from RC fuel, but the yield is abysmal.
This has been covered here a few times. RC fuel consists of mostly methanol, some NM and some synthetic oils. The distillation seems straight forward:
First fraction is collected at 64C, containing MeOH and a few percent NM ( they form an azeotrope with ca 6% NM), followed by the NM fraction at 101C.
Synthetic oils are left behind.
The NM concentration of the fuel was advertised as 16%. I tried to distill it, but no fraction came over after the MeOH fraction, even after heating
the mixture sufficiently (up to 180C).
I tried the same procedure with a different fuel source (since I suspected from the amateurish packaging that the NM concentration was way lower than
advertised) and had some success, but the yield is very low. I collected about 15ml starting from 1L.
I checked the density of the first fraction, but cant tell the NM concentration with tools I have since the densities of MeOH and NM are quite
similar.
Am I missing something here? Since I dont have a lot of experience I dont want to accuse people of lowering their NM percentage in the fuel they sell.
If someone has some insight/ similar experience pretty please enlighten me.
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RU_KLO
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Registered: 12-10-2022
Location: Argentina
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Maybe it does not contain nitromethane.
or the % it contains is in the azeotrope.
From our wiki:
It forms also azeotropes with other solvents, most importantly methanol (8% NM at 64.5 °C) and ethanol (26.8% NM at 76 °C).[5] Other sources list
the methanol azeotrope as 9% NM boiling at 64.6 °C,[6] 9% NM boiling at 64.4 °C[7] and as 10.5% NM boiling at 64.55 °C.[8]
So this means without loss, you should get aprox 16-9 = 6%.
Also from our wiki
To separate nitromethane from RC fuel, you will first have to fractionally distill the RC fuel. The first fraction that will distill is the NM-MeOH
azeotrope, containing 9% NM at 64.6 °C, which is close to the boiling point of pure methanol at 64.7 °C, meaning that unless you have a very long
column or a very efficient fractionating system, you will practically distill the MeOH along with the NM-MeOH azeotrope
probably this happens to you.
check our wiki for more info and ideas :
https://www.sciencemadness.org/smwiki/index.php/Nitromethane
ideas: Not tried, but maybe test with small quantity
Please be careful, explosive and fire hazzard.
using ethylene glycol (EG)
form here:
as NM Immiscible with alkanes, ethylene glycol, glycerol (our wiki)
as EG is uses as entrainer in methanol mixtures
check for more info on Extractive distillation using EG
Go SAFE, because stupidity and bad Luck exist.
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Deathunter88
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Registered: 20-2-2015
Location: Beijing, China
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Don't distill it directly from the bottle, wash it with water first to remove most of the methanol (methanol dissolves in water, NM doesn't). Then
distill the crude NM and you will have much better yield.
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