ANALYSIS OF 235U PRODUCTION BY CHEMICAL EXCHANGE IN U(IV) - U(VI) SYSTEM ON ANIONITE

Paula Raica1, D. Axente2

1Technical University of Cluj-Napoca, Department of Automation, 15 C.Daicoviciu Str., 400020 Cluj-Napoca, Romania, e-mail: Paula.Raica@aut.utcluj.ro
2National Institute for Research and Development of  Isotopic and Molecular Technologies,  400293 Cluj-Napoca 5, P.O.Box 700, Romania  e-mail: axente@s6.itim-cj.ro

A theoretical study for the  235U production  by chemical exchange in U(IV)-U(VI) system on anionite is presented.  An adsorbed band of U(VI) is eluted with a reducing agent in a series of resin packed columns.
The 235U isotope concentration profiles along the band were numerically calculated using an accurate mathematical model and simulations were carried out for  the case with product and waste withdrawal and feed supply. By means of numerical simulation an estimation of the band length, necessary for a desired enrichment degree, was obtained.
The required migration distance, the width of the enriched zone,  the volume of required resin and the number of columns,  for certain production of enriched 235U, are calculated for different operating conditions.  An analysis of the process scale for various column sizes is also presented.

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