Preparation and Characterization of Hydrous Zirconium Oxide Formed by Homogeneous Precipitation

Abstract

This paper reports on the preparation, characterization and study of the ion exchange behavior of hydrous zirconium oxides formed by homogeneous precipitation from zirconium oxychloride. The precipitants used were obtained by thermal decomposition of urea, sodium nitrite or ammo-nium carbonate. Seven compounds were prepared and characterized by thermal analysis, X-ray diffractometry and by surface area measurements. Amorphous forms were obtained in each case, a result that agrees with those obtained by conventional gel precipitation methodology. All these materials present surface area values of >148 m 2 .g-1 , determined after heat treatment at 50 °C. The ion exchange behavior of each hydrous zirconium oxide prepared was studied using K + as the exchanged species and the results compared with those obtained for hydrous zirconium oxide originally precipitated by the sol gel method.