Investigations into the influence of the most important parameters on the separation of rare earths as fission on products of Am-241 by means of ion exchange chromatography

A method has been developed for the quantitative isolation of the rare earth elements of neutron-irradiated Am 241 from the remaining fission products in order to determine their mass yields. For this, it was necessary to choose and elaborate and practically test a separation process. The method of choice was ion exchange chromatography which has long been used for the separation of nuclear fission products. Theoretical considerations by Glueckauf and the improved ideas of Giddings have been presented in an illustrative and connecting manner. The experience gained so far on the separation of fission products with ion exchangers was then described and evaluated with special regard to the separation of rare earth. The main part of the author's own experimental investigations concerned the testing of a set-up separation system. For this, suitable pretesting and system studies had to be performed corresponding to the measuring, apparative and experimental requirements. The various dependences of the effectivity of the separation system given by the separation power (separation factor) and the separation sharpness (band widths) on the working conditions such as elution agent, flow rate, grain size, as well as loading and form of the separation columns, were thus experimentally investigated and compared with the values required by the theory. In general, the predicted influences of the various parameters of the ion exchange chromatographic separation process agreed satisfactorily with the experiment. In the last part of the work, an optimized separation system to separate the fission products of an irradiation of Am 241 with reactor neutrons is tested and methods to determine the yields are checked. (orig./LH)