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Authors: J. Fritz, T. Vicsek and L. Simon
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Abstract  

The effect of a number of synthetic variables on the affinities of resorcinol-formaldehyde-iminodiacetic acid resins for137Cs and90Sr was determined. Porosity was introduced into the resins by inclusion of CaCO3 as a solid template during the synthesis. Among the variables examined were reaction temperature, reactant ratio, choice of basic catalyst, and amount of added template. Only reaction temperature was found to have a clearly defined influence on affinity. Cesium-137 affinity increased with increasing reaction temperature. Affinity for90Sr was independent of reaction temperature below reflux temperature, but dropped drastically for resins synthesized at reflux. These results are explained mechanistically. The reproducibility of the resin synthesis is also examined.

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Abstract  

The alkaline synthesis of porous phenol-formaldehyde polymers containing iminodiacetic acid is described. Porosity is induced by the addition of a finely divided solid material (template) that is insoluble under the reaction conditions. This template is removed by dissolution after the polymerization is complete. Silica gel, carbonate salts and various other salts are used as templates. Resins containing different phenols are synthesized and their effectiveness for the removal of radioactive cesium and strontium from alkaline concentrated sodium salt brines is examined. This matrix typifies the composition of soluble defense nuclear waste.

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Authors: J. Fritz, I. Ruzsa, G. Tusnády, T. Matolcsi and V. Totik

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Authors: P. Ormai, A. Fritz, J. Solymosi, I. Gresits, E. Hertelendi, Z. Szúcs, N. Vajda, Zs. Molnár and P. Zagyvai

Abstract  

In the execution of disposal of low and intermediate level radioactive wastes, it is important to evaluate accurately the kind and quantity of each radionuclide in the wastes. For such an evaluation, correlation of non-gamma-emitting nuclides based on gamma-emitting nuclides is recommended and regarded as a practical method. This method necessitates a completion of a highly accurate and reliable nondestructive assay system of gamma-emitting nuclides for practical use. In 1992, in support of the new waste disposal program in Hungary, Paks NPP initiated a waste characterization program to determine the radiological properties of its radwastes. A segmented gamma scanning system has been set up to measure the gamma-emitting nuclides in 200 litre low level drums following in-drum compaction. In the framework of the program a radiochemical analysis sub-program was started to determine the long-lived non-gamma emitting radionuclides, mainly those listed in the US regulatory document (10CFR61). The radionuclides of interest have been3H,14C,90Sr,55Fe,59Ni,99Tc,129I and TRUs. Sample preparation techniques and measurement methods have been selected and used. Newly developed or adopted methods have been tested on real liquid radwaste streams such as concentrates, ion-exchange resin and sludge. The measurements taken so far have revealed brand new information and data on radiological composition of waste of WWER-type reactors. In the next stage of the characterisation program attempt will be made for providing correlation factors between the gamma and non-gamma-emitting radionuclides in different waste streams. Short description of the methods and results on waste inventory are given by highlighting the problem areas.

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