PURIFICATION OF PHOSPHORIC ACID

摘要

The present invention relates to a method to remove metal ions in a phosphoric acid solution and, more particularly, to a method to reduce the concentration of metal ions with oxidation numbers from 2 to 7 inside of a phosphoric acid solution to below 100 ppb. The method comprises: a step of activating an ion exchange resin by passing an acid solution through the ion exchange resin; a step of filling a resin tower with the activated ion exchange resin and rinsing with deionized water; and a step of passing a phosphoric acid solution through the rinsed ion exchange resin.