Extraction and Analysis of Leachates from Synthetic Corium Samples

Abstract

The purpose of this project was to create synthetic corium samples and subsequently measure the leaching behaviour of these. The study aimed to see if different compositions affected the leaching behaviour and leaching rate. To accomplish this, corium samples were prepared using uranium dioxide (UO2), Nd, Sr and Ce (as a surrogate for plutonium). These samples were divided into two groups: one to be leached and one to be pressed into pellets. The surface area of the powders was measured, and the water in which the powders leached was analysed using an ICP-MS. The pellets were analysed using a SEM and XRD. XRD, SEM, and ICP-MS indicated that corium was successfully synthesised; however, the leachate concentration was too high for the ICP-MS to measure, indicating significant elemental release, but this meant that the exact concentration of the element could not be quantified. In conclusion, corium was synthesised and leached, but further work is needed to accurately quantify the leaching behaviour and elemental release. In addition, a leaching apparatus was developed to facilitate low-cost, accessible leaching experiments. This design, which is stackable and allows for simultaneous parallel testing, was made using CAD and can be 3D-printed, which removes reliance on specialised or expensive laboratory equipment.