A rapid geochemical spectrophotometric determination of tungsten with dithiol

E. P. Welsch

doi:10.1016/0039-9140(83)80203-3

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A rapid geochemical spectrophotometric determination of tungsten with dithiol

E. P. Welsch

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Abstract

1-g sample is decomposed with nitric and hydrofluoric acids, and after evaporation of the solution to dryness the residue is dissolved in concentrated hydrochloric acid. A clear aliquot is treated with stannous chloride to inhibit interferences. The blue tungsten dithiol complex is developed at a temperature of 85° over a half-hour period. The complex is extracted into 2 ml of heptane and the tungsten is determined spectrophotometrically with a sensitivity of 0.5 ppm. Fifty samples per man-day can be analysed in this manner.

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E. P. Welsch. 1983. A rapid geochemical spectrophotometric determination of tungsten with dithiol. https://doi.org/10.1016/0039-9140(83)80203-3

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