Process for preparing dioxalates of rare earths and ammonium and their use for the preparation of rare earth oxides, dioxalates and the obtained oxides

摘要

A process for preparing an ammonium rare-earth oxalate. This process consists in adding to a solution containing oxalate and ammonium ions a second solution containing a rare-earth compound, for example an yttrium nitrate. The double oxalate recovered after drying is calcined to give an yttrium oxide of determined morphology and suitable for the use of this oxide in the manufacture of luminescent compounds.