Review of the methods of graphite characterizations used in the nuclear installations carried out by the Analysis Chemical and Radiochemical laboratory of the CEA/Cadarache

Full text of publication follows: This work presents the methods for chemical and radiochemical analyses of the graphite issue of the Nuclear reactor 'Uranium Natural Graphite Gas' developed and applied on Chemical and Radiochemical Analysis Laboratory (LARC) at the CEA Cadarache. During the nuclear reactor operation, graphite, used as neutrons moderators, are irradiated due to high neutron production, which generated the formation of many activation products. The amount of radionuclides depends more particularly on the initial chemical composition of the graphite, on position in the nuclear reactor, and of the history of power. The main objectives were the radiochemical and chemical characterization of the graphite for study the long- term evolution or to prepare the decommissioning operations. For that, the laboratory have been working on the development of analytical methods to quantify as well as stable elements which may present and be activated or on the determination of the radionuclides produced. The results in particular dissolution (acid mixed digestion, combustion under oxygen..), analytical methods for separation (precipitation, liquid-liquid extraction, chromatography) and measurement techniques (alpha, gamma and X Spectrometry, liquid scintillation counting; ICP/AES and ICP/MS, ionic chromatography) are presented. We focus also on the complementarity of the techniques to carry out these inventories in an exhaustive way