Demineralization is the process of removing al dissolved minerals (Salt)/impurities present in water as Cations (positively charged) an Anions (negative charged). The Demineralization. The essentially consist of Cation exchanger (SAC). And Anion exchanger contains strong acid cation exchange resins in H+ form which can exchange stoichiometrically equivalent quantity of cations with which they come in contact these resins are regenerated wht HCL or H2SO4.