Preparation, characterization and thermal behavior of K2U4O13-Rb2U4O13 solid solutions

Abstract

Abstract The preparation and characterization of (K1−x Rb x )2U4O13 solid solutions has been studied for the x values in the range of 0 − 1. The solid solutions were prepared by heating K2U4O13 and Rb2U4O13 in required stoichiometry at about 600–700 ℃ for about 50 h in air atmosphere. The XRD patterns of the products suggest formation of the solid solutions in full composition range of Rb2U4O13 and K2U4O13. The cell volume of the crystal unit cell of solid solutions changes linearly with Rb atom % in (Rb + K) present in the solid solutions and follows Vegard's law. The solid solutions when heated in Ar/He atmospheres at 900 ℃ produce corresponding low valent uranate solid solutions (K1−x Rb x )2U4O12 or their mixtures.