Authors:H. Vinsova, R. Konirova, M. Koudelkova, and V. Jedinakova-Krizova
The uptake of technetium on bentonite materials has been studied from the point of view of the characterization of long-term radioactive elements behavior in nuclear waste repository. It is generally known that bentonite materials show an excellent cation-exchange capacity and on the other hand a poor uptake of anions. The aim of our research has been to find out the conditions suitable for technetium sorption on selected bentonite under oxidizing conditions. The influence of the addition of different materials (e.g., activated carbon, graphite, Fe2+, Fe) with bentonite, the effect of solid:aqueous phase ratio and a pH value on the percentage of technetium uptake and on the Kd values were tested.
The kinetics (1–1000 minutes shaking) of 5·10–4M Eu sorption from 0.1M HNO3 onto the support XAD-7 impregnated with approximately equimolecular mixture of DBDECMP and dicarbollide depends appreciably on the technique of the preparation of the impregnated support. The highest distribution factors are obtained if DBDECMP is only used to impregnate the support and dicarbollide is added directly to the aqueous phase. The rate of sorption increases slightly with adding 1·10–5M surfactants but the effect is too weak for practical use. The best stripping agent found is an equimolecular mixture of DCTA and citric acid at pH 7. This work is a continuation of the investigation1–3 of the synergic effect occurring in the sorption of low concentrations of europium due to the simultaneous presence of H+[(C2B9H8Cl3)2Co]– (abbreviated as dicarbollic acid, HB) and di-butyl-N-di-ethyl-carbamoylmethyl phosphonate (DBDECMP) on a suitable support. The system is promising for the separation of small amounts of tervalent transuranium and lanthanoid elements from radioactive waste. In the previous paper we have investigated quasi-equilibrium sorption of various Eu concentrations (24 hour shaking). In the present paper kinetic data of sorption and quasi-equilibrium data on desorption are studied. Preliminary kinetic studies of similar systems2,3 have shown that the rate of both the sorption and desorption processes in this type of system is one of the decisive factors in the practical application of this separation method. Whereas in the previous paper1 both DBDECMP and CMPO (octyl-phenyl-N,N-diisobutyl carbamoylmethyl phosphineoxide) combined with dicarbollide were studied, for reasons given previously1 (mainly a higher synergic effect) herein DBDECMP was only investigated.
A rapid automated flow injection analysis (FIA) procedure was developed for efficient separation of Am and Pu from each other
and from interfering matrix and radionuclide components using a TRU-resin™column. Selective Pu elution is enabled via on-column reduction. The separation was developed using on-line radioactivity
detection. After the separation had been developed, fraction collection was used to obtain the separated fractions. In this
manner, a FIA instrument functions as an automated separation workstation capable of unattended operation.
Authors:Silvia Dulanská, Boris Remenec, L’ubomír Mátel, and Erik Durkot
A rapid separation method has been developed which allows measurement of plutonium, americium and strontium isotopes in the
radioactive sludge from Nuclear power plant A1 Jaslovske Bohunice (NPP A1) with high chemical recoveries and effective removal
of matrix interferences. This method uses different commercial products stacked AnaLig® Pu02, AnaLig® Sr01 and TRU® Resin cartridges from IBC Advanced Technologies and Eichrom Technologies. The method allows the rapid separation of plutonium,
strontium and americium using a single multi-stage column in the vacuum box (cartridge technology) with rapid flow rates to
minimize sample separation time. The 239,240Pu, 238Pu and 241Am were determined by alpha spectroscopy, 90Sr was counted on TRICARB 2900 TR by Cerenkov counting of its progeny 90Y.
The uptake of a few polyvalent ions Ca2+ Cu2+, Zn2+, Cd2+, UO2+, Cr3+, Y3+, Ce3+, Nd3+, Sm3+, Tb3+, Tm3+, Yb3+, Lu3+, Zr4+, Hf4+, Sn4+, Nb5+, Se6+, Mo6+ and W6+ at very small concentrations has been studied over ceric tungstate exchanger. A good column variety of the material was prepared by mixing ceric sulphate in 2N H2SO4 and aqueous solution of sodium tungstate in suitable proportion. The ratio of cerium: tungstate was obtained to be 11. Separation of carrier-free95Nb from95Zr and113mIn from113Sn have been carried out by applying a very simple chemical procedure over the column of ceric tungstate. The -spectrum of separated95Nb and113mIn products were found to be of high radionuclidic purity. The separation procedure took less than 15 min and the yields were close to 100%.
Authors:Stefano Dugheri, Giorgio Marrubini, Nicola Mucci, Giovanni Cappelli, Alessandro Bonari, Ilenia Pompilio, Lucia Trevisani, and Giulio Arcangeli
, and concentration of the target analytes [ 3, 4 ]. Analysts generally use cartridge-type devices for SPE that contain packed solid particles of porous chromatographic material. The mechanism of action of SPE is the interaction between the solid sorbent
Authors:Arezoo Hassan Noori, Mohammad Rezaee, Maryam Kazemipour, and Hossein Ali Mashayekhi
various samples [ 8 ]. SPE is a well-established method for the preconcentration and isolation of various analytes from different matrices. In SPE, selection of an appropriate sorbent is an important strategy in the elaboration of analytical procedure, and
Authors:Ebru Büyüktuncel, Esra Porgalı, and Serpil Özkara
Molecular imprinting has become an interesting method to produce recognition sites in a macromolecular matrix for the preparation of selective sorbents over the past decades [ 1 ]. Molecularly imprinted polymers