title: Methods for the separation of rhenium, osmium and molybdenum applicable to isotope geochemistry.
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 1M in hydrochloric acid and 1M in sodium chloride.
authors.affiliation: U.S. Geological Survey, 981 National Center, Reston, VA 22092 U.S.A.
authors.forename: J W
authors.initials: JW
authors.lastname: Morgan
authors.forename: D W
authors.initials: DW
authors.lastname: Golightly
authors.forename: A F
authors.initials: AF
authors.lastname: Dorrzapf