Study on variation of equilibrium constant in some uni-bivalent ion exchange systems

Ion exchange resins in chloride and iodide form were equilibriated with sulphate and oxalate ion solution of seven different concentrations varying from 0.010 M to 0.050 M respectively. The equilibrium study was carried in the temperature range of 30 to 45 degreesC. For both Cl-/SO42- and I-/C2O42- uni-bivalent exchanges the value of equilibrium constant (K) increases with rise in temperature, indicating the endothermic ion exchange reaction. Also K value for Cl-/SO42- ion exchange reaction was observed to be seater than I-/C2O42- ion exchange reaction i.e., at 30 degreesC the K value of CI-/SO42- ion exchange was calculated to be 20 while for I-/C2O42- ion exchange it was calculated to be 0.260 which was due to the difference in relative selectivity of ion exchange resin towards I- and Cl- ions.