0000000000172109
AUTHOR
Akihiko Yokoyama
Extraction behavior of rutherfordium into tributylphosphate from hydrochloric acid
The extraction behavior of rutherfordium (Rf) into tributylphosphate (TBP) from hydrochloric acid (HCl) has been studied together with those of the lighter group-4 elements Zr and Hf. The extractability of261Rf,169Hf, and85Zr into TBP was investigated under identical conditions in 7.2–8.0 M HCl by on-line reversed-phase extraction chromatography. The percent extractions of Rf, Hf, and Zr into the TBP resin increase steeply with increasing HCl concentration, and the order of extraction is Zr > Hf ≈ Rf. By considering the order of chloride complexation among these elements, it is suggested that the stability of the TBP complex of Rf tetrachloride is lower than those of Zr and Hf.
Anionic Fluoro Complex of Element 105, Db
We report on the characteristic anion-exchange behavior of the superheavy element dubnium (Db) with atomic number Z=105 in HF/HNO3 solution at the fluoride ion concentration [F−]=0.003 M. The resul...
Chemical studies on rutherfordium (Rf) at JAERI
SummaryChemical studies on element 104, rutherfordium (Rf), at JAERI (Japan Atomic Energy Research Institute) are reviewed. The transactinide nuclide261Rf has been produced in the reaction248Cm(18O, 5n) at the JAERI tandem accelerator with the production cross section of about 13 nb. On-line anion-exchange experiments on Rf together with the lighter homologues, group-4 elements Zr and Hf, in acidic solutions have been conducted with a rapid ion-exchange separation apparatus. From the systematic study of the anion-exchange behavior of Rf, it has been found that the properties of Rf in HCl and HNO3solutions are quite similar to those of Zr and Hf, definitely confirming that Rf is a member of …
Anion-exchange Behavior of Rf in HCl and HNO3 Solutions
H. Haba,∗,a K. Tsukada,a M. Asai,a S. Goto,a,b A. Toyoshima,a,c I. Nishinaka,a K. Akiyama,a M. Hirata,a S. Ichikawa,a Y. Nagame,a Y. Shoji,c M. Shigekawa,c T. Koike,c M. Iwasaki,c A. Shinohara,c T. Kaneko,b T. Maruyama,b S. Ono,b H. Kudo,b Y. Oura,d K. Sueki,d H. Nakahara,a,d M. Sakama,e A. Yokoyama,f J. V. Kratz,g M. Schadel,h and W. Bruchleh Advanced Science Research Center, Japan Atomic Energy Research Institute, Tokai-mura, Ibaraki 3191195, Japan Department of Chemistry, Faculty of Science, Niigata University, Niigata-shi, Niigata 950-2181, Japan Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka-shi, Osaka 5600043, Japan Department of Chemistry, Graduate Sc…
Adsorption of Db and its homologues Nb and Ta, and the pseudo-homologue Pa on anion-exchange resin in HF solution
Anion-exchange chromatography of element 105, dubnim (Db), produced in the 206 Cm( 19 F, 5n) 262 Db reaction is investigated together with the homologues Nb and Ta, and the pseudo-homologue Pa in 13.9 M hydrofluoric acid (HF) solution. The distribution coefficient (K d ) of Db on an anion-exchange resin is successfully determined by running cycles of 1702 chromatographic column separations. The result clearly indicates that the adsorption of Db on the resin is significantly different from that of the homologues and that the adsorption of anionic fluoro complexes of these elements decreases in the sequence of Ta ≈ Nb > Db > Pa.
Fluoride Complexation of Element 104, Rutherfordium
Fluoride complexation of element 104, rutherfordium (Rf), produced in the 248Cm(18O,5n)261Rf reaction has been studied by anion-exchange chromatography on an atom-at-a-time scale. The anion-exchange chromatographic behavior of Rf was investigated in 1.9-13.9 M hydrofluoric acid together with those of the group-4 elements Zr and Hf produced in the 18O-induced reactions on Ge and Gd targets, respectively. It was found that the adsorption behavior of Rf on anion-exchange resin is quite different from those of Zr and Hf, suggesting the influence of relativistic effects on the fluoride complexation of Rf.
Hexafluoro complex of rutherfordium in mixed HF/HNO3 solutions
Formation of anionic fluoride-complexes of element 104, rutherfordium, produced in the 248 Cm( 18 O, 5n) 261 Rf reaction was studied by anion-exchange on an atom-at-a-time scale. It was found that the hexafluoro complex of Rf, [RfF 6 ] 2- , was formed in the studied fluoride ion concentrations of 0.0005-0.013 M. Formation of [RfF 6 ] 2- was significantly different from that of the homologues Zr and Hf, [ZrF 6 ] 2- and [HfF 6 ] 2- ; the evaluated formation constant of [RfF 6 ] 2- is at least one-order of magnitude smaller than those of [ZrF 6 ] 2- and [HfF 6 ] 2- .