ION EXCHANGE AND DIALYSIS THE REMOVAL OF IONS

ION EXCHANGE AND DIALYSIS THE REMOVAL OF IONS FROM SOLUTION USING RESINS

RESIN PARTICLE AND BEADS

Ion exchange of monovalent cations: (assume y = 1) For most solutions A = B

Ion exchange of mixed-valent cations: (assume y = 1)

CROSSLINKING TO MAKE ION EXCHANGE RESINS

Selectivity of Ion Exchange Resins In Order of Decreasing Preference Strong acid cation Barium Lead Calcium Nickel Cadmium Copper Zinc Magnesium Potassium Ammonia Sodium Hydrogen Strong base anion Iodide Nitrate Bisulfite Chloride Cyanide Bicarbonate Hydroxide Fluoride Sulfate

Chelating Cation Resin Selectivities for Metal KM/Caa Hg+2. . . . 2, 800 Cu+2. . . . 2, 300 Pb+2. . . . 1, 200 Ni+2. . . 57 Zn+2. . . . 17 Cd+2. . . . 15 Co+2. . . . 6. 7 Fe+2. . . . 4. 7 Mn+2. . . . 1. 2 Ca+2. . . . 1 ® Selectivity coefficient for the metal over calcium ions at a p. H of 4

Cost of Commercially Available Resins ® Resin Cost($/ft 3) Strong acid cation. . 45 -130 Weak acid cation. . . 120 -160 Strong base anion. . . 210 -270 Weak base anion. . . 210 -260 Chelating cation. . . 350 -650

SMALL SCALE ION EXCHANGE COLUMNS

SKID-LOADED SMALL SCALE ION EXCHANGE P

LARGE-SCALE ION EXCHANGE COLUMNS

POSITIONING OF RESIN BEADS FOR A MIXED BED JUST AFTER BACKWASHING

Improved Nitrate Removal from Drinking Water by Ion Exchange: Testing a Hydraulic Device for Improved Regeneration

IXCalc. TM A powerful computer program

High Performance Liquid Chromatography (DEAE and CM)</

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ELECTRODIALYSIS