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Methods for the separation of rhenium, osmium and molybdenum applicable to isotope geochemistry

J. W. Morgan·D. W. Golightly·A. F. Dorrzapf
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Abstract

Effective methods are described for the chemical separation of rhenium, osmium and molybdenum. The methods are based on distillation and anion-exchange chromatography, and have been the basis for rhenium—osmium isotope studies of ore deposits and meteorites. Successful anion-exchange separation of osmium requires both recognition and careful control of the osmium species in solution; thus, distillation of osmium tetroxide from a mixture of sulfuric acid and hydrogen peroxide is preferred to anion-exchange. Distribution coefficients measured for perrhenate in sulfuric acid media are sufficiently high ( K d > 500) for rhenium to be directly loaded onto an ion-exchange column from a distillation residue and subsequently eluted with nitric acid. Polymerization of molybdenum species during elution is prevented by use of a solution that is 1 M in hydrochloric acid and 1 M in sodium chloride.

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J. W. Morgan, D. W. Golightly, A. F. Dorrzapf. 1991. Methods for the separation of rhenium, osmium and molybdenum applicable to isotope geochemistry. https://doi.org/10.1016/0039-9140(91)80045-2

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