Thermodynamics of ion exchange equilibrium for some uni-univalent and divalent reaction systems using strongly basic anion exchange resin Indion FF-IP

The study on thermodynamics of ion exchange equilibrium for uni-univalent Cl-/I-, Cl-/Br-, and uni-divalent Cl-/SO42-, Cl-/C2O42- reaction systems was carried out using ion exchange resin Indion FF-IP. The equilibrium constant K was calculated by taking into account the activity coefficient of ions both in solution as well as in the resin phase. For uni-univalent ion exchange reaction systems, the equilibrium constant K’ were also calculated by considering mole fraction of ions in the resin phase. The K values calculated for uni-univalent and uni-divalent anion exchange reaction systems were observed to increase with rise in temperature, indicating the endothermic exchange reactions having enthalpy values of 22.45, 28.57, 17.84, 15.97 kJ/mol, respectively. KEY WORDS: Ion exchange equilibrium, Equilibrium constant in standard state, Apparent equilibrium constant, Enthalpy, Endothermic reaction Bull. Chem. Soc. Ethiop. 2008, 22(3), 415-421.