Dissolving sulfur in the flotation foam

[Ultrax]

Hi there,

I need to dissolve the suspension of sulfur in the flotation foam, preferably as efficiently as possible. Carbon disulfide - too expensive and toxic. Acetone - dissolves poorly.
Maybe someone tried the dissolution of sulfur in a concentrated solution of NaOH 30%-50% and can advise something? Before I will experiment on my own

Thanks!

 

[orvi]

Sulfur goes into the solution of strong hydroxide quite OK - heating helps a lot. Solid bigger chunks react very very slow as reaction is only going on the surface. If it is fine sulfur, hydroxide is your choice.

 

[Ultrax]

Yes, it's fine sulfur particles. What is NaOH minimal percentage reasonable enough?
Thanks for your help

 

[orvi]

Yes, it's fine sulfur particles. What is NaOH minimal percentage reasonable enough?
Thanks for your help

I didnt tested this, but when I used around 20% it gone fast enough for me. Should be easy to make 5 parallel beakers tests with various strengths of NaOH. Visual analytics very convenient. And don´t be affraid of red colour forming polysulfides are strange compounds. Don´t forget that thiosulfate also forms by this reaction - just a reminder that it can cause problems later in terms of possible gold chelation, if conditions allow it to do so.

 

[Ultrax]

I didnt tested this, but when I used around 20% it gone fast enough for me. Should be easy to make 5 parallel beakers tests with various strengths of NaOH. Visual analytics very convenient. And don´t be affraid of red colour forming polysulfides are strange compounds. Don´t forget that thiosulfate also forms by this reaction - just a reminder that it can cause problems later in terms of possible gold chelation, if conditions allow it to do so.

Na2S2O3 and Na2S are not critical for the flotation foam at this stage.
I will try 20%, thank you

 

[Lou]

Ammonia also works. Sulfur is gone when last washing yields no red poly sulfide.

Very objectionable!