OH-anion exchange of water is performed in order to exchange removed anions for hydroxide ions. Due to the combination of OH-anion exchange and Н-cation exchange, anions as well as cations are removed and exchanged for (OH-) and (H+) ions, in other words, chemical (ion-exchange) water demineralization takes place.
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* The text is taken from:
A.S. Kopylov, V.M. Lavygin, V.F. Ochkov, "Water-treatment in power energetics"
(M. MEI Publishing House, 2003).

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