Formation of Rare Earth Phosphates in NaCl-KCl Based Melts.

Reaction of chlorides of 15 rare earth elements (yttrium, lanthanum and all lanthanides except promethium) with sodium orthophosphate was studied in the melts based on the NaCl-KCl equimolar mixture at 750 °C in an inert atmosphere. The experiments were conducted at various phosphate-to-REE molar ratios. Chemical and phase composition of the reaction products was determined as well as the particle size distribution of the REE phosphates formed at the phosphate-to-REE molar ratios corresponding to various degrees of REE precipitation. [ABSTRACT FROM AUTHOR]