Crystallization of lanthanide phosphates and fluorides from wet-process orthophosphoric acid

Crystallization of rare earth phosphates and fluorides on granular seedings of rare earth phosphates or fluorides is studied when passing a continuous flow of the wet-process phosphoric acid through a fixed bed of solid phase in a thermostatically controlled column. It is shown that the time of solution-seeding contact is the process controlling characteristic independent of column parameters and seeding mass