WERKWIJZE VOOR HET TERUGWINNEN VAN EEN LUMINESCEREND OXISULFIDE, VANADAAT OF OXIDE VAN TEN MINSTE YTTRIUM EN/OF EEN ELEMENT UIT DE LANTHAANREEKS.

摘要

A method of recovering a rare earth phosphor from a mixture which contains this phosphor and at least one sulphide and/or selenide of zinc and/or cadmium. The mixture is treated in an aqueous alkaline solution which contains a hypohalogenite and whose pH is larger than 12. The rare earth phosphor is subsequently separated from the liquid and washed with water, optionally after rinsing with a diluted acid.