Structure and stability analysis of basaltic glasses for immobilizing simulated actinides Nd, Ce and La

Abstract

Taking a power reactor in China as the object, the simulated actinides basaltic glasses were prepared by the solid-state melt method using Nd, Ce and La to simulate the actinides Am, Np and U. The XRD, SEM-EDX, XPS, Raman and DSC results show that the loading of the simulated actinides in basaltic glass can be up to 36 wt.%, and excess simulated actinides lead to oxyapatite crystals precipitation in the glasses; about half of Ce4+ in basaltic glasses is reduced to Ce3+; the simulated actinides may break Si-O bonds in glass networks, but overall there were no serious effects; the thermal stability of the basaltic glasses with the simulated actinides content increased first, and reduce when the content of more than 25 wt.%. All the samples have good leaching resistance and the leaching rates of Nd, Ce and La are 4 orders of magnitude lower than Si and Na.