[ShivaTecAnalyst]

I am attempting to analyze CdS, in solution, for sulfur concentration via ICP-OES. I have not yet found a way to keep all the sulfur in solution. Upon reaction with HCl Cd enters solution and sulfur leaves as gaseous H2S. Is there a way to maintain the sulfur in solution, perhaps via oxidation to sulfate? If so, what is the best method to procede? Thanks.

[Mr Peanut]

At your risk, blah, blah, blah and all that.

I have had moderate success with H2O2 in converting S- to SO4--, However, I was working with H2S. You may be able to use it with CdS with some modifications. Perhaps a cold finger reflux with neutral H2O2. (H2O2 nasty at 30%)

Combustion in an oxygen bomb with paper pulp as a support has also worked well for me in converting all S to SO4 for total sulfur determinations. Place a few ml of NaOH sol'n in the bomb as an absorber. If you have access to a bomb contact its manufacturer for ideas. I’d try 0.1g CdS and 0.5 g paper in the thimble.

[kevins]

Please try to convert the S-- to SO4 by dilute Bromine Water.