The sulfur content in metal sulfides can be determined after oxidative dissolution with bromine water-CCI4 at 50°C by modified EDTA titration. The sulfides were quantitatively oxidized to SO42- without evolving H2S, and the metal cations were removed by cation exchange on an H-type column. Sulfate was precipitated as BaSO4, and the remaining Ba2+ was subsequently titrated with EDTA at pH = 10. The standard deviation for the determined sulfur in the metal sulfides, some of which can be hardly dissolved in usual mineral acid media, is about a few %. The method can be carried out with sample amounts containing as little as 1.5-2 mg sulfur.
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