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Determination of gold, indium, tellurium and thallium in the same sample digest of geological materials by atomic-absorption spectroscopy and two-step solvent extraction

A.E. Hubert·T. T. Chao
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Abstract

A rock, soil, or stream-sediment sample is decomposed with hydrofluoric acid, aqua regia , and hydrobromic acid-bromine solution. Gold, thallium, indium and tellurium are separated and concentrated from the sample digest by a two-step MIBK extraction at two concentrations of hydrobromic add. Gold and thallium are first extracted from 0.1 M hydrobromic acid medium, then indium and tellurium are extracted from 3 M hydrobromic acid in the presence of ascorbic acid to eliminate iron interference. The elements are then determined by flame atomic-absorption spectrophotometry. The two-step solvent extraction can also be used in conjunction with electrothermal atomic-absorption methods to lower the detection limits for all four metals in geological materials.

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A.E. Hubert, T. T. Chao. 1985. Determination of gold, indium, tellurium and thallium in the same sample digest of geological materials by atomic-absorption spectroscopy and two-step solvent extraction. https://doi.org/10.1016/0039-9140(85)80145-4

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