Polverone - 8-5-2004 at 23:52
Following a rather old method, today I prepared hydroxylamine as its HCl salt from sodium nitrite, sodium (meta)bisulfite, and hydrochloric acid. The
paper said that the hydroxylamine salt was separated from the other salts by extraction with hot alcohol. I used a large amount of hot alcohol to
extract my boiled-almost-to-dryness reaction products. Now that the alcohol has cooled a sort of insoluble "oil" has separated from it at
the bottom of the vessel. I wonder what this is. Perhaps more importantly, does anyone know how soluble hydroxylamine hydrochloride is in ethanol, or
what a suitable substitute solvent might be? Denatured alcohol is full of junk, and 95% food grade is expensive, so I'd like to optimize my
solvent use or replace it with something less expensive.
Edit: the oil crystalized. The solubility question stands.
[Edited on 5-9-2004 by Polverone]
Polverone Has No References?
S.C. Wack - 9-5-2004 at 21:30
In Lange's its 4.4/100 by weight. Merck gives 1g/19ml in ethanol and 1g/8ml methanol. So if one uses
the-most-widely-sold-in-gallon-cans-in-the-US brand there may be some problems, as it is alleged to be 38.25-45% ethanol, 52.5-61.3% methanol, and
.45-2.5% methyl isobutyl ketone. The refs sure do say that a saturated boiling ethanol solution should precipitate most of the hydrochloride on
cooling.
You may want to try a test precipitation of the sulfate from its aqueous solution with your "alcohol", in case this comes up again.
do I have egg on my face!
Polverone - 10-5-2004 at 09:32
You're right, the value was in Lange's. In the future I shall be less hasty to have forum members do my homework for me 
.