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Autori: C.F. Petre and F. Larachi
Editorial: Journal of Separation Science, 29, p.144-152, 2006.
A capillary electrophoresis protocol was developed for the identification and separation of inorganic polysulfides simultaneously with other inorganic sulfur-bearing species coexisting in aqueous hydrosulfide/sulfur solutions. The electrophoretic separation of thiosulfate, sulfate, hydrosulfide, sulfite, tetrathionate and polysulfide was achieved at pH values between 8.2 and 12.2. The peaks attributed to the polysulfide species were strongly sensitive to pH. Capillary electrophoresis analysis of hydrosulfide/sulfur solutions at different pH values permitted possible identification of two forms of polysulfide: S42- and S32-. Upon exposure to air at ambient temperature, thiosulfate was the main oxidation product of hydrosulfide/sulfur solutions mainly in the first 60 min, when hydrosulfide was rapidly consumed. Analysis of the oxidation reaction products provided retrospectively tentative evidence that the peaks separated and identified as tri- and tetrasulfide may be ascribed to polysulfide.
Cuvinte cheie: polysulfides, capillary electrophoresis, oxidation, separation