When you think about it, you’re effectively building a moonshine still. And I have ..um... allegedly run one once or twice...
As you heat the mixture you will watch the liquid temp rise gradually but the air temp in the line arm will stay room temp and then all of a sudden go right to the boiling point of methanol, at this point you turn on the water to your condenser and viola-methanol starts dripping out. Methanol has a lower boiling point than ethanol (149vs173) and is the stuff that makes you go blind from lousy moonshiners.
The boil will stay at this temp until the methanol is gone and then all of a sudden jump up to the next phase change, the boiling point of ethanol and then eventually water.
In theory if you had a tall reflux column still you could probably save the nitro.
Otherwise a centrifuge would probably work too...