Sciencemadness Discussion Board

Making ammonium hypophosphite

MineMan - 3-6-2021 at 20:32

I want to expire by using this compound in pyrotechnics. I have the sodium salt. Any ideas how to make the ammonium? The only patent I found makes a solution.

draculic acid69 - 3-6-2021 at 21:01

Add HCL to free the acid filter out the salt then neutralize with ammonia then evaporate to dryness
Also was expire meant to mean explore or r U contemplating suicide by
ammonium hypophosphite explosion?

Belowzero - 3-6-2021 at 22:14

Quote:

Also was expire meant to mean explore or r U contemplating suicide by
ammonium hypophosphite explosion?


Yes I am worried too!
Otherwise that is a very funny typo :)

unionised - 3-6-2021 at 23:40

Just make sure it doesn't disproportionate to phosphine, or you might be doing more expiring than you planned.

woelen - 4-6-2021 at 00:06

Quote: Originally posted by draculic acid69  
Add HCL to free the acid filter out the salt then neutralize with ammonia then evaporate to dryness [...]

How effective is this at removing the sodium from the solution?
Also, can ammonium hypophosphite easily be dried? Isn't that compound extremely hygroscopic?

Probably you also need excess concentrated HCl to get decent separation of NaCl from the solution and evaporating that also can be quite cumbersome (nasty fumes, evaporation will be slow).

I know of a similar method for making perchloric acid from conc. HCl and concentrated solution of NaClO4. In that case, however, you can boil off any excess HCl (boiling to 140 C or so) and concentrate the solution to 60% without leaving a noticeable amount of HCl. With hypophosphite I do not think this is safe. You most likely decompose the acid, giving lots of phosphine and a big chance of unintended ignition.

[Edited on 4-6-21 by woelen]

draculic acid69 - 4-6-2021 at 01:38

Quote: Originally posted by woelen  
Quote: Originally posted by draculic acid69  
Add HCL to free the acid filter out the salt then neutralize with ammonia then evaporate to dryness [...]

How effective is this at removing the sodium from the solution?
Also, can ammonium hypophosphite easily be dried? Isn't that compound extremely hygroscopic?

Probably you also need excess concentrated HCl to get decent separation of NaCl from the solution and evaporating that also can be quite cumbersome (nasty fumes, evaporation will be slow).

I know of a similar method for making perchloric acid from conc. HCl and concentrated solution of NaClO4. In that case, however, you can boil off any excess HCl (boiling to 140 C or so) and concentrate the solution to 60% without leaving a noticeable amount of HCl. With hypophosphite I do not think this is safe. You most likely decompose the acid, giving lots of phosphine and a big chance of unintended ignition.

[Edited on 4-6-21 by woelen]


As for effectiveness of removing the salt I'm not 100%sure how much precipitates
and how much stays dissolved. I think if one uses acetone as a solvent for the acidification most salt should precipitate. Also I think hypophosphorus acid dissolves in ether if one wishes to force more salt out. As for the ammonium salt I'm not sure if it's dry-able or not.

MineMan - 4-6-2021 at 03:00

Quote: Originally posted by draculic acid69  
Add HCL to free the acid filter out the salt then neutralize with ammonia then evaporate to dryness
Also was expire meant to mean explore or r U contemplating suicide by
ammonium hypophosphite explosion?


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