First phase of the spent fuel autoclave leaching experiments (SF-ALE) at sck cen

Deep geological disposal of high level nuclear waste, such as spent nuclear fuel is being considered by several countries, including Belgium and Germany. Ultimately, such a scenario considers contact between underground water and the fuel due to aging and corrosion of the materials. The SF-ALE research program contributes to a better understanding of the release of radionuclides from the fuel as a function of the surrounding environment. An improved autoclave setup was developed, allowing to simultaneously investigate the release of water-soluble and gaseous components from the fuel. Six experiments (three on irradiated UO2 and three on irradiated MOX fuel samples) have recently been started and will run over 1.5 years, followed by an extension of another 1.5 years. A description of the hot cell equipment, analytical techniques used and the microstructural characterization of the irradiated fuel samples will be presented.