scholarly journals Study on Halide Ions Selectivity of Industrial Grade Anion Exchange Resin Auchlite A-378

Author(s):  
P.U. Singare ◽  
A.N. Patange

The thermodynamic approach was applied to predict the trend selectivity of industrial grade anion exchange resin Auchlite A-378 in chloride form towards iodide and bromide ions in the solution. The study was conducted by performing the Clˉ/Iˉ and Clˉ/Brˉ uni-univalent ion exchange reactions under gradually increasing temperature conditions. The thermodynamic equilibrium constants K values were used to calculate the enthalpies of the two uni-univalent ion exchange reactions. It was observed that the K values for Clˉ/Iˉ ion exchange reaction were higher than Clˉ/Brˉ exchange reaction under identical experimental conditions. Also the enthalpy values for the two uni-univalent ion exchange reactions were calculated as -39.51 and -18.38 kJ/mol respectively. The high K and low enthalpy values obtained for Clˉ/Iˉ ion exchange reaction is responsible for higher selectivity of the resin towards iodide ions as compared to that towards bromide ions, when both the ions are present in the same solution.

Author(s):  
P.U. Singare ◽  
A.N. Patange

The selectivity behaviour of nuclear grade anion exchange resin Auchlite ARA-9366 in chloride form towards iodide and bromide ions in the solution was studied. The trend in selectivity of the resin was predicted on the basis of thermodynamics of Clˉ/Iˉ and Clˉ/Brˉ uni-univalent ion exchange reactions. It was observed that the equilibrium constants K values for Clˉ/Iˉ ion exchange reaction were higher than that calculated for Clˉ/Brˉ exchange under identical experimental conditions. Also the enthalpy values for the two uni-univalent ion exchange reactions were calculated as -47.87 and -36.14 kJ/mol respectively. The high K and low enthalpy values obtained for Clˉ/Iˉ ion exchange reaction as compared to that obtained during Clˉ/Brˉ exchange supports higher selectivity of the resin towards iodide ions as compared to that towards bromide ions, when both the ions are present in the same solution.


Author(s):  
Pravin U. Singare ◽  
Akmal L. Khan Mohammed ◽  
N.N. Dixit

The present paper deals with the thermodynamic of uni-univalent and uni-bivalent ion exchange reactions using nuclear grade anion exchange resin Indion-223. It was observed that with rise in temperature the equilibrium constants K values for H+/K+ uni-univalet ion exchange reaction increases from 0.01710 to 0.02374. Similarly for H+/Ca2+ uni-bivalet ion exchange reaction the equilibrium constants K values increases from 0.000397 to 0.000639. The increase in K values with rise in temperature for both the reactions indicates its endothermic nature having the enthalpy change values of 22.72 and 38.92 kJ/ mol respectively. The technique used here can be extended further to standardise the process parameters in order to bring about the efficient separation of the desired ionic species from the solution


Author(s):  
Pravin U. Singare ◽  
Akmal L. Khan Mohammed ◽  
N.N. Dixit

The present paper deals with the ion exchange equilibrium studies of uni-univalent and uni-bivalent ion exchange reactions using nuclear grade anion exchange resin Indion-223 in H+ form towards Na+ and Ca2+ ions in the solution. It was observed that with rise in temperature the equilibrium constants K values for H+/Na+ uni-univalet ion exchange reaction increases from 0.01389 to 0.01855. Similarly for H+/Ca2+ uni-bivalet ion exchange reaction the equilibrium constants K values increases from 0.000397 to 0.000639. The increase in equilibrium constant values with rise in temperature indicate endothermic ion exchange reactions having the enthalpy change values of 25.55 and 38.92 kJ/ mol respectively.


Author(s):  
P.U. Singare ◽  
A.N. Patange

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.


Author(s):  
P.U. Singare ◽  
A.N. Patange

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.


2020 ◽  
Vol 244 ◽  
pp. 474-481
Author(s):  
Olga Cheremisina ◽  
Elizaveta Cheremisina ◽  
Maria Ponomareva ◽  
Аleksander Fedorov

Rare earth elements (REEs) are valuable and strategically important in many high-technology areas, such as laser technology, pharmacy and metallurgy. The main methods of REE recovery are precipitation, extraction and sorption, in particular ion exchange using various sorbents, which allow to perform selective recovery and removal of associated components, as well as to separate rare earth metals with similar chemical properties. The paper examines recovery of ytterbium in the form of coordination compounds with Trilon B on weakly basic anion exchange resin D-403 from nitrate solutions. In order to estimate thermodynamic sorption parameters of ytterbium anionic complexes, ion exchange process was carried out from model solutions under constant ionic strength specified by NaNO3, optimal liquid to solid ratio, pH level, temperatures 298 and 343 K by variable concentrations method. Description of thermodynamic equilibrium was made using mass action law formulated for ion exchange equation and mathematically converted to linear form. Values of equilibrium constants, Gibbs free energy, enthalpy and entropy of the sorption process have been calculated. Basing on calculated values of Gibbs energy, a sorption series of complex REE ions with Trilon B was obtained over anion exchange resin D-403 from nitrate solutions at temperature 298 K. Sorption characteristics of anion exchange resin have been estimated: total capacity, limiting sorption of complex ions, total dynamic capacity and breakthrough dynamic capacity.


Author(s):  
Pravin U. Singare ◽  
Akmal L. Khan Mohammed ◽  
N.N. Dixit

In the present investigation the uni-univalent and uni-bivalent ion exchange reactions were studied using nuclear grade anion exchange resin Indion-223 in H+ form. It was observed that for H+/Na+ uni-univalet ion exchange reaction, with rise in temperature the equilibrium constants K values increases from 0.01389 to 0.01855. Similarly increase in K values was observed from 0.000177 to 0.000333 for H+/Mg2+ uni-bivalet ion exchange reaction. The increase in equilibrium constant values with rise in temperature indicate endothermic ion exchange reactions having the enthalpy change values of 25.55 and 51.46 kJ/ mol respectively. It is expected that the present study 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.


Author(s):  
György Pátzay ◽  
József Dobor ◽  
Emil Csonka ◽  
Gábor Lozsi ◽  
Ferenc Feil

Borate ion exchange capacity of Purolite NRW600 strong base anion resin in hydroxide form and mixed bed NRW600+NRW100 ion exchange was investigated with static experiments. Anion exchange resin was saturated with 0.1–45 g/dm3 concentration boric acid solution in a static mixer at 20, 30, 40 and 50 °C at 150 rpm for 24 hours. Remaining borate content of saturation solutions was deter-mined with ion chromatography and ICP-OES. The amount of fixed borate as borate anions increased with the saturation borate concentration as well as in case of simple anion exchange as in case of mixed bed.Column sorption-elution study was carried out by using strong base anion exchange resins (Purolite NRW600 and Amberlite IRN78). Resins in hydroxide and in chloride forms were saturated in column with 5–40 g/dm3 boric acid solution in excess. The resin was then eluted with 200 cm3 salt free water with 5 cm3/min at 25 °C and then eluted by 1 mol/dm3 sodium-sulfate solution with 5 cm3/min. The effluent was collected and analyzed for borate content by titrimetric method. In chloride form the resin adsorbed and released much less borate. Effective borate and polyborate sorption needs hydroxide ions in resin phase.


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