A new method for alkaline-earth monouranates preparation by solid state and chlorination reactions

Abstract

Alkaline-earth monouranates with the formula MUO4 (M = Ca, Sr, Ba) were synthesized using a novel method which consists of a combination of solid state reaction between U3O8 and alkaline-earth oxide or carbonate in air, and chlorination reaction of the product of the solid state reaction using Cl2(g) as chlorinating agent. The chlorination temperature was optimized to obtain the desired uranate. The products obtained after the chlorination reactions were washed with deionized water and thermally treated to crystallize the uranates. MgUO4 could not be synthesized and presents a different behavior due to the similarity in the starting temperatures of the magnesium and uranium oxide chlorination reactions. The monouranates were characterized by PXRD, SEM and chemical analysis to determinate their structures.