METHOD OF REMOVING STRONTIUM AND CALCIUM IONS FROM AQUEOUS SOLUTIONS (OPTIONS) Russian patent published in 2004 - IPC

FIELD: water treatment. SUBSTANCE: cleansing of mineralized aqueous solution from strontium and calcium resides in their isolation onto bulk electrode with developed surface under cathode polarization conditions from 0.05-1 N NaCl solution containing strontium in presence of calcium salt. Process is conducted at continuous aeration of electrolyte until constant value of potential is attained, which deviates from stationary immersion potential by -0.1 to -1.6 V against silver chloride electrode. Bulk electrode with developed surface may be carbon fiber or oxidized carbon fiber, or granulated sorbent based on Mn(III,IV) oxides, or inorganic sorbent: carbon-supported Mn(III, IV) oxides. EFFECT: increased completeness of cathodic precipitation of jointly present strontium and calcium in the form of lower-soluble carbonates. 8 cl, 10 ex