Sciencemadness Discussion Board

What to do with my Ammonium Bicarbonate?

Sulaiman - 28-8-2021 at 23:30

I bought ammonium carbonate (baking quality) as a source of ammonium ions,
Ammonia is easily released by the action of a basic solution, or heat, or in my case, higher ambient temperatures :(

The jar that I am storing it in leaks gas from the decomposition.
I'm not sure if a well sealed container is a good idea, given that there will be continuous decomposition.

Q1 is it safe to store ammonium bicarbonate powder in a well sealed glass jar with ambient temperatures often around 38oC?

I am considering decomposing the ammonium bicarbonate to make ammonia solution for storage.
I think that my liquid storage bottles (350ml ginger beer bottles) should be able to withstand the pressure.

Q2 what is the minimum useful concentration of ammonia solution for stock use?

For each mole of ammonia released there will also be one mole of CO2,
scrubbing it would be relatively expensive,
working outdoors I'm not concerned about CO2 safety.

Q3 in general, would a little carbon dioxide in my ammonia solution be significant in hobby chemistry?

Q4 can you suggest any other useful compound that I could convert my ammonium bicarbonate into ?
(without exotic equipment or ingredients, preferably not requiring conc. sulphuric or nitric acid)

karlos³ - 28-8-2021 at 23:38

My A to Q4 would be, dry ammonium acetate maybe?
You can make that from the baking quality stuff with GAA, you just need to account for the CO2 release with a large balloon or such.
But the produced ammonium acetate will be dry, well, pretty much, depends on the ammonium bicarbonate.

Fyndium - 29-8-2021 at 01:14

Ammonium formate or formamide can also be useful. They can be generated by reacting your bicarb with concentrated formic acid.

fredsci93 - 29-8-2021 at 01:46

Definitely the carbon dioxide can be a problem depending on the reaction, if it's being used in a general context for neutralizing solutions or the like it would be fine, however, if you’re doing something like metal complex chemistry it could introduce problems. I would agree that making an ammonium salt would be better than making an ammonia solution, or you could use the ammonium carbonate in place of ammonia, in the aforementioned general contexts it would be just as effective as an ammonia solution.

BauArf56 - 29-8-2021 at 02:36

A3, if you are making ammonia solution from it, yes it is a problem. i already tried to heat ammonium bicarbonate alone and to lead the gas in water, but got no ammonia solution. But if you mix this with a base (which will bond with the CO2) you get a nice ammonia generator. I made mine using calcium hydroxide, so as a bonus inside reaction flask there was some potentially useful calcium carbonate.

RustyShackleford - 29-8-2021 at 02:46

Q1: yes, ive been able to store it for years in a jam jar
Q2: ~15-20%
if you add a solution of sodium hydroxide to the ammonium bicarbonate and heat it, it will generate ammonia gas while the CO2 stays dissolved as sodium carbonate. this should make for absolutely minimal CO2/carbonate contamination

Q3: unlikely
Q4: ammonium formatate and ammonium chloride are somewhat useful in organic synthesis.

Sulaiman - 29-8-2021 at 02:52

Both interesting,
but I just realised that the ammonium bicarbonate costs me about USD1 per kg.
so I'll keep it in its 'auto-ventilated' (poor sealing) jar,
and buy more if it becomes unusable.

Thanks for all of the answers and suggestions.
(especially to use a basic solution rather than heat)
(KOH and NaOH are quite cheap here)

[Edited on 29-8-2021 by Sulaiman]

Tsjerk - 29-8-2021 at 03:12

A solution of ammonia and CO2 basically is the same as a solution of ammonium bicarbonate:

CO2 + H2O <--> H2CO3
H2CO3 + NH3 <--> NH4HCO3

What you can do is adding NaOH to a solution of ammonium bicarbonate, you will get a solution of sodium carbonate in ammonia. When you distill the ammonia you will get rid of the sodium, although you could probably already precipitate a lot of sodium carbonate upon cooling when using concentrated solutions. Maybe you can get it more concentrated by adding ammonium bicarbonate to a solution of sodium hydroxide. Or add a cold concentrated solution of sodium hydroxide to a suspension of ammonium bicarbonate.

Ammonia and CO2 gas react o ammonium bicarbonate as long as there is water around, so as long as you keep the gasses inside the storage container you can keep it indefinitely (as long as the container doesn't explode).

[Edited on 29-8-2021 by Tsjerk]

rockyit98 - 29-8-2021 at 10:03

you can make NH4Cl and NaHCO3 by mixing it with sub zero solution of NaCl .(Solvay process)
if you mix it with powdered gypsum at room temperature you can also make (NH4)2SO4 and CaCO3.

Fyndium - 29-8-2021 at 10:11

Should it then as well react with CaCl2?