[horse]

For generating ammonium gas, I usually use ammonium sulfate because its dirt cheap and can be found pure in big 3kg tubs for $20. Ammonium nitrate from cold packs isn't practical, not here anyway because they contain "a mixture of nitrate salts" whatever the hell that means. It can be used to generate ammonia, but there is so much other crap in there it takes up too much space in the gas generator and is less effective. Are there any other cost effective sources of ammonium salts?

[billnotgatez]

Did you look at these WIKI
https://en.wikipedia.org/wiki/Category:Ammonium_compounds
https://en.wikipedia.org/wiki/Ammonium

[horse]

I just found out that these cold packs are actually urea + NH4NO3. I can hydrolyse the urea, but to maximise the yield of ammonium salts would it be viable to add sulphuric acid to the water to trap the released ammonia?