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Thermodynamics of Ion-exchange reaction in predicting the ionic selectivity of Auchlite ARA-9366 and Auchlite A-378 anion exchange resins

Singare P. U., Patange A. N.

International Letters of Chemistry, Physics and Astronomy

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2014

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Vol. 6

1--7

EN

The paper deals with predicting the iodide ion selectivity of nuclear and non-nuclear grade anion exchange resins. The ionic selectivity prediction was made on the basis of thermodynamic data of Clˉ/I ˉ ion exchange reaction. It was observed that with rise in temperature from 30.0 °C to 45.0 °C, the equilibrium constant (K) values were observed to decreases from 59.77x10-2 to 23.77x10-2 for Auchlite ARA-9366 resins and from 9.01x10-2 to 4.05x10-2 for Auchlite A-378 resins. The decrease in K values with rise in temperature, indicate exothermic ion exchange reactions having enthalpy values of -47.87 and -39.51 kJ/mol respectively. The high K and low enthalpy values obtained for Auchlite ARA-9366 resins indicate their greater selectivity for the iodide ions in the solution as compared to Auchlite A-378 resins, when both the resins are present in chloride form.

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Thermodynamic study to evaluate the selectivity behaviour of nuclear grade resin Indion-223 towards some univalent ions

Singare P. U., Mohammed A. L. K., Dixit N. N.

International Letters of Chemistry, Physics and Astronomy

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2014

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Vol. 15

22--29

EN

The present paper deals with the application of thermodynamic concept in understanding the preferential selectivity of nuclear grade anion exchange resin Indion-223 in H+ form towards Na+ and K+ ions in the solution. In the study it was observed that the equilibrium constants K values for H+/Na+ and H+/K+ uni-univalet ion exchange reactions increases from 0.01389 to 0.01855 and from 0.01710 to 0.02374 respectively as the temperature increases from 35.0 °C to 45.0 °C. The increase in K values with rise in temperature suggests endothermic ion exchange reactions having the enthalpy change values of 25.55 and 22.72 kJ/ mol respectively. Based on difference in K values and enthalpy values for the two uni-univalent ion exchange reactions, the preferential selectivity of the resin for the univalent ions in the solution was predicted. From the results of present study, it appears that the experimental technique used here can be applied further to understand the ionic selectivity of different industrial grade ion exchange resins. It is expected that such studies will provide valuable information in order to decide about the selection of those resins for efficient separation of various ionic species present in the industrial waste water effluents.

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Study on preferential selectivity of nuclear grade resin Indion-223 towards some bivalent ions

Singare P. U., Mohammed A. L. K., Dixit N. N.

International Letters of Chemistry, Physics and Astronomy

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2014

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Vol. 15

11--21

EN

In the present paper attempts are made to understand the selectivity of nuclear grade cation exchange resin Indion-223 in H+ form towards Ca2+ and Mg2+ bivalent ions in the solution based on thermodynamic concept. It was observed that with rise in temperature the equilibrium constant K values for H+/Ca2+ uni-bivalet ion exchange reactions increases from 0.000397 to 0.000639. Similarly for H+/Mg2+ uni-bivalet ion exchange reactions the equilibrium constant K values increases from 0.000177 to 0.000333. The increase in equilibrium constant values with rise in temperature indicate endothermic ion exchange reactions having the enthalpy change values of 38.92 and 51.46 kJ/ mol respectively. The difference in K values and enthalpy values were used to predict the selectivity behaviour of the resin towards the Ca2+ and Mg2+ bivalent ions in the solution. The thermodynamic concept of the present study can be applied to understand the selectivity behaviour of different nuclear as well as non-nuclear grade resins towards wide range of ionic species present in the exchanging liquid medium.

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Ion-exchange reaction thermodynamics to study the selectivity behaviour of nuclear and non-nuclear grade anion exchange resins

Singare P. U., Patange A. N.

International Letters of Chemistry, Physics and Astronomy

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2014

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Vol. 6

8--15

EN

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 ion exchange reactions performed by using the two resins. During Clˉ/Brˉ exchange reactions, with rise in temperature from 30.0 °C to 45.0 °C, the equilibrium constant (K) values were observed to decreases from 8.15x10-2 to 6.06x10-2 for Auchlite ARA-9366 resins and from 2.16x10-2 to 1.10x10-2 for Auchlite A-378 resins. The decrease in K values with rise in temperature, indicate exothermic ion exchange reactions having enthalpy values of -36.14 and -18.38 kJ/mol respectively. The high K 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.