GreenD - 10-4-2012 at 11:28
Hi,
I know that by heating ammonium carbonate one can make ammonium hydroxide, but I'm not sure how efficiently this can be done, especially without open
flame or heat gun.
How cold would your refluxer's solvent need to be to condense ammonia gas efficiently? It just occured to me you could perhaps bubble it through H2O,
but then there are some problems there as well (final concentration, etc).
If there is an OTC route to getting ammonium hydroxide, I'm all for it, but from my understanding it's not exceptionally easy to buy.
Thank yas.
Pulverulescent - 10-4-2012 at 11:42
Reaction of alkali will displace HN<sub>3</sub> from an ammonium salt!
The evolved NH<sub>3</sub> is led to water (stirred) through an inverted funnel to prevent suck-back . . .
Stirring is necessary because HN<sub>4</sub>OH is lower in density than water!
GreenD - 10-4-2012 at 11:45
Ok, if you have excess ammonium salt, is your final product going to be ~30% ammonia aq? Or does it go higher?
Pulverulescent - 10-4-2012 at 11:55
It's 30% @ NTP; density - 0.880.
annaandherdad - 10-4-2012 at 12:00
Don't know where you are, but getting NH4OH OTC is pretty easy around here (California USA). Dilute solutions sold in grocery stores, and somewhat
more concentrated solutions in hardware stores. And I've never had any trouble ordering concentrated solution from chem supply places.
MrHomeScientist - 10-4-2012 at 12:31
Woelen's also got a good method for concentrating ammonia on his site somewhere. I believe it was simply taking a large amount of household ammonia
(~5%), heating it, and leading the gas into a smaller volume of water. In his setup it doubled the concentration, but that could of course be adjusted
by changing the amounts of each liquid used.
Hexavalent - 10-4-2012 at 15:07
I assume that one could lead the ammonia gas into a dilute household solution of ammonia (simply adding more gas to a dilute solution) or even that
Janitorial 10% stuff to further enhance concentration?
DJF90 - 10-4-2012 at 15:49
The household ammonia I found in the stores near me was 10%, intended mostly for cleaning windows I suspect. Smells too much to do anything else with.
barley81 - 10-4-2012 at 15:52
Yeah, but the ammonia at the store frequently has surfactants and other things in it. Distilled water is better because you ensure that the product
isn't contaminated with whatever is in the ammonia. If you know your ammonia solution is pure and clean, then bubbling ammonia gas into it in order to
increase the concentration is more efficient than using distilled water.