Lanthanon (Rare-Earth) Sodium Sulphate Precipitations

Abstract

IN addition to using sodium sulphate in the classical manner to effect a separation of the light (cerium group) lanthanons, leaving the heavy group and yttrium in solution, I have found it advantageous to precipitate the whole of the 'soluble' double sulphates. This is achieved (except for the equivalent of 0·2 gm. per 1. of oxide) simply by salting out. In hot brine, solubilities of the yttrium group are reduced to less than 1 per cent of the minimum obtainable in practice with excess of sodium sulphate in hot aqueous solution.