Studies on focusing chromatography. Separation of radioactive nuclides in neutron irradiated uranium

U, Np and F.P. in neutron irradiated uranium oxide were separated from each other using focusing chromatography. Individual nuclides were determined by γ-ray spectrometry. As complex forming agent, 1.0M lactic acid and 0.05M nitrilotriacetic acid (NTA) were tried, and various mixtures of hydrochloric acid and sodium chloride as complex decomposing agent. The efficacy of the forming and decomposing agents for the separation was observed with various solutions of electrolytes. In all cases, Tc, Mo, Ru, Rh, I, Zr and one fraction of Np migrated toward the anode. As the hydrogen ion concentration of the complex decomposing solution was decreased, these nuclides became more easily separable. Te and a small amount of Np generally remained in the area of the spot where the sample had been introduced. Sr and Ba always migrated toward the cathode. Rare earth elements were sensitive not only to the kind of complex forming agent used but also to the pH value of the decomposing solution. Np manifested three different modes of focusing characteristic, their proportions varying with the conditions of the separation system. The concluding result was that the system of 0.1M sodium chloride-1.0 M lactic acid was found the most suitable for separating these multi-component mixtures. (author)