Kinetics of fission products accumulation on structural materials

The aim of the present work was to reveal the kinetics of the accumulation of some possible contaminant on the surfaces of structural materials (zirconium alloys and 08H18N10T stainless steel) in the primary circuit of Paks NPP. The kinetics of adsorption and desorption of iodide, caesium and cerium ions were investigated by quartz crystal microbalance (QCM) installed into a flow cell. The results on thin layers were confirmed by immersing experiments, using radiotracer technique and ??-spectrometry to detect the traced ions on the surfaces. Experiments were carried out in electrolyte solution which was similar to the cooling water. All measurements were carried out at room temperature. Both adsorption and desorption were found to be fast, taking only several seconds; time constants were also evaluated.