Sciencemadness Discussion Board

ammonium thiocyanate

jamit - 8-11-2021 at 08:55

I was able to acquire an old bottle of ammonium thiocyanate. the only problem is that the chemical has degraded a bit, at least that's what i think... the color is no longer a white power but "yellowish-red". when I put it into solution, it is red.

Could this be because of iron contamination? I will attempt to recrystallize it but I'm not sure what contamination it could be. Any help on what happened to the original chemical, ammonium thiocyanate?

I will try recrystallization to recover the original chemical.

fredsci93 - 8-11-2021 at 12:41

It could be sulfides and poly sulfides due to degradation of the thiocyanate (SCN- + O2 ---> CO2 + 1/2N2 + S- and other more complex reactions) in either case a recrystallisation should clean it up.

woelen - 9-11-2021 at 00:00

Keep in mind that recrystallization of ammonium thiocyanate is very difficult. The chemical is really hygroscopic and once you have it dissolved in water, you will have a hard time getting it dry again. You most likely need vacuum over H2SO4 or NaOH to get it dry again.