PRODUCTION OF ULTRAPURE WATER

摘要

PURPOSE: To provide a production method for ultrapure water in which impurity cations are substantially not contained except hydrogen ions. CONSTITUTION: The production method of ultrapure water incorporates a process for passing water through a single bed of a hydrogen ion type strongly acidic cation-exchange resin in which the cations of impurities except a hydrogen ion are at most 0.1 percentage by equivalent of the whole exchange equivalent of ion-exchange resin, or through a mixed bed of the hydrogen ion type strongly acidic cation-exchange resin and regeneration type strongly basic anion-exchange resin.