Phosphor purification process

摘要

A process for removing suspected heavy metal contaminants from a manganese-arsenic activated, zinc orthosilicate phosphor comprises contacting the phosphor, in an aqueous slurry, with an organic chelating agent such as an alkali metal salt of ethylenediamine tetraacetate and subsequently rinsing, filtering, drying and sieving the phosphor and baking the sieved phosphor.