P.U. Singare, A.N. Patange, Ion-Exchange Reaction Thermodynamics to Study the Selectivity Behaviour of Nuclear and Non-Nuclear Grade Anion Exchange Resins, ILCPA Volume 25, International Letters of Chemistry, Physics and Astronomy (Volume 25)
    In the present investigation, attempts were made to understand the difference in bromide ion selectivity of the two closely related anion exchange resins Auchlite ARA-9366 and Auchlite A-378 in chloride form. The selectivity difference was predicted based on the thermodynamic equilibrium constants and enthalpy values of Clˉ/Brˉ<sup> </sup> ion exchange reactions performed by using the two resins. During Clˉ/Brˉ exchange reactions, with rise in temperature from 30.0<sup> </sup>°C to 45.0 °C, the equilibrium constant (<i>K</i>) values were observed to decreases from 8.15x10<sup>-2</sup> to 6.06x10<sup>-2</sup> for Auchlite ARA-9366 resins and from 2.16x10<sup>-2</sup> to 1.10x10<sup>-2</sup> for Auchlite A-378 resins. The decrease in <i>K</i> values with rise in temperature, indicate exothermic ion exchange reactions having enthalpy values of -36.14 and -18.38 kJ/mol respectively. The high <i>K</i> and low enthalpy values obtained for Auchlite ARA-9366 resins indicate their greater selectivity for the bromide ions in the solution as compared to Auchlite A-378 resins.
    Auchlite A-378, Auchlite ARA-9366, Enthalpy, Ionic Selectivity, Nuclear Grade Ion Exchange Resin, Thermodynamic Equilibrium Constant, Uni-Univalent Exchange