Simultaneous separation of tin and bismuth from water and sea water by flotation with thionalide

Summary A method is described for the simultaneous flotation of low g l^–1 levels of tin and bismuth in water and sea water. Tin(IV) and bismuth(III) in a 1000 ml sample is coprecipitated with thionalide at pH 2–3. The precipitate is floated with the aid of a surfactant and small nitrogen bubbles, then dissolved in acetone and digested with nitric and perchloric acids for hydride generation-atomic absorption spectrophotometry. Recoveries of tin and bismuth at the levels of 20 g added to water and sea water were more than 88%.