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Abstract  

Fast, discontinuous separation procedures are described for zirconium, niobium, technetium and antimony from fission products. Other rapid separation methods from aqueous solutions are summarized. The combination of a gas jet recoil transport system with a continuous solvent extraction technique and with a thermochromatographic separation method is presented. The application of such procedures to the investigation of new and already known short-lived nuclides is illustrated by some examples.

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Abstract  

A survey is given of the educational programs at German universities and research institutions. The program at the University of Mainz is outlined in some detail.

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Trennung von Spaltprodukten durch Extraktionschromatographie

II. Trennung von Mutter-tochter-paaren

Journal of Radioanalytical and Nuclear Chemistry
Authors:
R. Denig
,
N. Trautmann
, and
G. Herrmann

Abstract  

The performance of columns to be used for separations of fission products by extraction chromatography was studied as a function of the loading of the support with extractant, of the flow rate and the temperature of the elutriant. Separations of molybdenum-technetium, antimony-tellurium, zirconium-niobium and thorium-protactinium were used as examples to prove the effectiveness of this method.

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Trennung von spaltprodukten durch Extraktionschromatographie

III. Auftrennung eines spaltproduktgemisches

Journal of Radioanalytical and Nuclear Chemistry
Authors:
R. Denig
,
N. Trautmann
, and
G. Herrmann

Abstract  

The separation of fission products which form anionic species in mineral acids and of uranium and neptunium from samples of neutron-irradiated uranium is described. The method used is extraction chromatography with tri-n-butylphosphate (TBP) and di-(2-ethylhexyl)-orthophosphoric acid (HDEHP) as extractants and polytrifluoromonochloroethylene powder as the solid support. In the first column Zr, U and Np are extracted with TBP from 8N HNO3/NaClO3. In the second column, HDEHP is applied as extractant and 9N HCl/NaClO3 as the mobile phase for the isolation of Nb, Sb, and I, and in the third column (HDEHP), the rare earths and Mo are extracted from 0.1N HCl. Finally with the fourth column (TBP), Te and Tc are isolated from 6N HCl. These four groups of elements are further separated by elution from the columns. From the final effluent containing Ru, Rh, Cs, Sr, and Ba, Ru is distilled from HClO4, and Rh is precipitated with NH4OH. The determination of chemical yields with X-ray fluorescence techniques is described for Zr, Mo, Te, Cs, Ce and U.

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Trennung von Spaltprodukten durch extraktionschromatographie

I. Bestimmung der verteilungskoeffizienten

Journal of Radioanalytical and Nuclear Chemistry
Authors:
R. Denig
,
N. Trautmann
, and
G. Herrmann

Abstract  

The possibilities for the separation of a complex fission product mixture by extraction chromatography have been investigated. Here the partition coefficients between three solvents and hydrochloric acid are reported for the following elements: Zn(II), Ge(IV), As(III), As(V), Se(IV), Zr(IV), Nb(V), Mo(VI), Tc(IV) Ru(III), Ru(IV), Rh(III), Ag(I), Cd(II), In(III), Sn(IV), Sb(III), Sb(V), Te(IV), I(oxidized), Cs(I), Ce(III), Tb(III), Tm(III), Ac(III), Th(IV), Pa(V), U(VI), Np(IV), Np(VI). As solvents tri-n-butylphosphate (TBP), tri-n-octylamine (TOA) and di-(2-ethylhexyl)-orthophosphoric acid (HDEHP) have been used. The partition coefficients have been measured by batch-experiments in which the solvents were adsorbed on polytrifluoromonochloroethylene powder.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
J. Alstad
,
G. Skarnemark
,
F. Haberberger
,
G. Herrmann
,
A. Nähler
,
M. Pense-Maskow
, and
N. Trautmann

Abstract  

The H-0.3 liquid-liquid centrifuge applied for rapid and efficient separation of two liquid phases, and the HG-0.1 gas-liquid centrifuge used to separate the gas phase stemming from a gas jet transportation system and the liquid phase, have been further improved. New centrifuges have been produced of PEEK, a plastic material, which makes them resistant to most aqueous and organic solutions. The performance with respect to time behavior and phase purity is comparable to the titanium centrifuges used so far. The H-0.3 centrifuge has been applied to solvent extraction studies of Zr, Nb, Mo, Hf, Ta, W and Pa from HF solutions into tri-n-octylamine.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
K. Aleklett
,
R. Brandt
,
M. Bronikowski
,
V. Butsev
,
B. Chasteler
,
G. Dersch
,
G. Feige
,
E. Friedlander
,
E. Ganssauge
,
G. Haase
,
J. Herrmann
,
D. Hoffman
,
B. Judek
,
P. Kosma
,
B. Kulakov
,
E. Langrock
,
D. Lee
,
W. Loveland
,
F. Pille
,
N. Porile
,
W. Schulz
, and
G. Seaborg

Abstract  

In recent years the question of the unusual behavior of projectile fragments formed in the interaction of relativistic heavy ions with copper nuclei was studied using nuclear chemistry techniques. As targets we used various copper disk arrangements. It is not the intention of this conference contribution to give a complete account of the entire procedure and its results. However, we want to present a few more recent experimental findings, some of them even in a preliminary form. We want to stimulate the discussion about the entire problem which might be part of the so-called anomalon phenomenon, as observed in the field of relativistic heavy ion interactions with a few other techniques such as nuclear emulsions or bubble chambers.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
M. Pham
,
M. Betti
,
P. Povinec
,
M. Benmansour
,
V. Bünger
,
J. Drefvelin
,
C. Engeler
,
J. Flemal
,
C. Gascó
,
J. Guillevic
,
R. Gurriaran
,
M. Groening
,
J. Happel
,
J. Herrmann
,
S. Klemola
,
M. Kloster
,
G. Kanisch
,
K. Leonard
,
S. Long
,
S. Nielsen
,
J.-S. Oh
,
P. Rieth
,
I. Östergren
,
H. Pettersson
,
N. Pinhao
,
L. Pujol
,
K. Sato
,
J. Schikowski
,
Z. Varga
,
V. Vartti
, and
J. Zheng

Abstract  

A new certified reference material (CRM) for radionuclides in sea water from the Irish sea (IAEA-443) is described and the results of the certification process are presented. Ten radionuclides (3H, 40K, 90Sr, 137Cs, 234U, 235U, 238U, 238Pu, 239+240Pu and 241Am) have been certified, and information values on massic activities with 95% confidence intervals are given for four radionuclides (230Th, 232Th, 239Pu and 240Pu). Results for less frequently reported radionuclides (99Tc, 228Th, 237Np and 241Pu) are also reported. The CRM can be used for quality assurance/quality control of the analysis of radionuclides in water samples, for the development and validation of analytical methods and for training purposes. The material is available in 5 L units from IAEA (http://nucleus.iaea.org/rpst/index.htm).

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