On the reactive occlusion of the (uranium trichloride plus lithium chloride plus potassium chloride) eutectic salt in zeolite 4A

摘要

The interaction between the (uranium trichloride + lithium chloride + potassium chloride) eutectic sail: and zeolite 4A has been studied by temperature-resolved synchrotron powder X-ray diffraction, evolved gas analysis and differential scanning calorimetry, between 300 and 900 K. The onset of salt occlusion by the zeolite has been detected at 450 K. Evidence of a reaction between zeolitic water and uranium trichloride, leading to the formation of uranium dioxide, has appeared at 600 K. The uranium dioxide particle size increases from 2 nm at 600 K to 25 nm at 900 K - an indication of their extra-zeolitic location. No appreciable degradation of the zeolite structure has been observed. (C) 2000 Elsevier Science B.V. All rights reserved. [References: 20]