hydroxide

Hydroxide ions are released by the resin as anions are adsorbed from the liquid phase. The effect is elimination of acidity in the liquid and conversion of the resin to a salt form. Typically, the resin is restored to the OH form with a 4% solution of NaOH.
The hydroxide form is also used in salt splitting applications.
resin N(CH3)3OH^-+Na+ + Cl^-
resin N(CH3)3Cl^- + Na⁺ + OH^-
Salt forms of a strong base anion exchangerare used to remove other anions for which the resin has greater selectivity.
2 resin N(CH3)3Cl^- +2Na+SO4^2-
(resin N(CH3)3)2SO4^2- +2 Na+ +2Cl^-

ChEBI: Hydroxide is an oxygen hydride. It has a role as a mouse metabolite. It is a conjugate base of a water.