Re: ammonium citrate recipe?
Houshold ammonia has soap and other goodies in it. You
are looking for ¨clear ammonia¨ without those. Look at
paint stores (used as solvent for primer-sealer) or
pharmacies and what you find there will also have a more
accurate percentage on the label.
CHEERS FROM GUATEMALA (RETURNING TO B´DOS NEXT
WEEK)
BOB
On Fri, 13 Mar 2009 22:11:39 -0400
etienne garbaux <photographeur@nerdshack.com> wrote:
Paul wrote:
A while back (in the archives) there was a reference to
making your own amm citrate using household ammonia and
citric acid. However, the reference to the original
recipe is no longer available on the internet...
Has anyone done this and used it in their workflow? Is it
possible to get an exact recipe for doing this...?
The original post mentions a citric acid solution and
adding ammonia (household ammonia???) but doesn't list %
solution for the citric...
Is "household ammonia" available that is nothing but
ammonium hydroxide (no surfactants or other additives)?
I'm not sure it is in the US.
In any case, you can never be certain of the
concentration of your ammonia without testing, so no
formula will do. You will have to measure either the
concentration of the ammonium hydroxide or some
indicative parameter of the resulting ammonium citrate
solution. The proportion to prepare a neutral solution
is 5.365:1 by weight of citric acid (crystals) to ammonia
(NH3), but it is up to you to determine how much ammonia
by weight is in each volume of your ammonia water.
Adding citric acid to the ammonia water "until the
ammonia smell disappears" would be a crude first
approximation.
In 1911, the ACS published an article on preparing
neutral ammonium citrate solution by measuring
conductivity:
http://pubs.acs.org/doi/abs/10.1021/ie50032a008
Here are some instructions from 1888, from "A Treatise
On Beverages" by Charles Herman Sulz:
Solution Of Citrate Of Ammonia: Prepare by neutralizing
12 ozs. of citric acid with ammonia 11 fl. ozs., or
sufficient, and add distilled water to yield 20 fl. ozs.
of product. Store in bottles free from lead. Spec. grav.
1209 [this should probably be "1.209"]. Citric acid
combines with ammonia, forming ammonium citrate and
water. The solution is clear and colorless, has a saline
taste, and should not change either litmus or
turmeric-paper.
Note that author Sulz does not specify the concentration
of ammonia, hence the caveat "or sufficient" and the
instructions to test the resulting solution with
indicators (note that the specified indicator papers
would give at best a somewhat better approximation than
doing it by nose).
Best regards,
etienne
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