Anion exchange behavior of MIIAl layered double hydroxides: a molecular dynamics and DFT study

2020 ◽  
Vol 22 (35) ◽  
pp. 19758-19768 ◽  
Author(s):  
Xiao-Jie Zhao ◽  
Yu-Quan Zhu ◽  
Si-Min Xu ◽  
Hui-Min Liu ◽  
Pan Yin ◽  
...  
Keyword(s):  
Molecular Dynamics ◽  
Ion Exchange ◽  
Exchange Reaction ◽  
Anion Exchange ◽  
Layered Double Hydroxides ◽  
Dft Study ◽  
Sewage Disposal ◽  
Supramolecular Materials ◽  
Ion Exchange Reaction ◽  
Double Hydroxides

The ion exchange reaction has been extensively used in the field of synthesis of functionalized supramolecular materials such as layered double hydroxides (LDHs), ion-embedded batteries, sewage disposal and so on.

Intercalation of nucleotides into layered double hydroxides by ion-exchange reaction

2005 ◽  
Vol 28 (1-4) ◽  
pp. 137-145 ◽  
Author(s):  
Sumio Aisawa ◽  
Yuuki Ohnuma ◽  
Kimihiro Hirose ◽  
Satoshi Takahashi ◽  
Hidetoshi Hirahara ◽  
...  
Keyword(s):  
Ion Exchange ◽  
Exchange Reaction ◽  
Layered Double Hydroxides ◽  
Ion Exchange Reaction ◽  
Double Hydroxides

Structural and microstructural changes during anion exchange of CoAl layered double hydroxides: anin situX-ray powder diffraction study

2010 ◽  
Vol 43 (3) ◽  
pp. 434-447 ◽  
Author(s):  
Rune E. Johnsen ◽  
Frank Krumeich ◽  
Poul Norby
Keyword(s):  
Phase Transformation ◽  
Exchange Reaction ◽  
Anion Exchange ◽  
Powder Diffraction ◽  
Layered Double Hydroxides ◽  
Two Phase ◽  
X Ray ◽  
Double Hydroxides ◽  
Anion Exchange Reaction

Anion-exchange processes in cobalt–aluminium layered double hydroxides (LDHs) were studied byin situsynchrotron X-ray powder diffraction (XRPD). The processes investigated were CoAl–CO3→ CoAl–Cl → CoAl–CO3, CoAl–Cl → CoAl–NO3and CoAl–CO3→ CoAl–SO4. The XRPD data show that the CoAl–CO3→ CoAl–Cl process is a two-phase transformation, where the amount of the CoAl–CO3phase decreases exponentially while that of the CoAl–Cl phase increases exponentially. Energy-dispersive X-ray spectroscopy (EDXS) studies of a partially chloride-exchanged CoAl–CO3LDH sample along within situXRPD data suggested that the individual particles in the CoAl–CO3sample are generally anion-exchanged with chloride one at a time. In contrast with the CoAl–CO3→ CoAl–Cl transformation, the XRPD data show that the reverse CoAl–Cl → CoAl–CO3process is a one-phase transformation. Rietveld refinements indicate that the occupancy factors of the carbon and oxygen sites of the carbonate group increase, while that of the chloride site decreases. In the CoAl–Cl → CoAl–NO3anion-exchange reaction, the XRPD patterns reveal the existence of two intermediate phases in addition to the initial CoAl–Cl and final CoAl–NO3phases. Thein situdata indicate that one of these intermediates is a mixed nitrate- and chloride-based LDH phase, where the disorder decreases as the nitrate content increases. The XRPD data of the partial CoAl–CO3→ CoAl–SO4anion-exchange reaction show that the process is a two-phase transformation involving a sulfate-containing LDH with a 1H polytype structure.

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

2014 ◽  
Vol 30 ◽  
pp. 44-50 ◽  
Author(s):  
P.U. Singare ◽  
A.N. Patange
Keyword(s):  
Ion Exchange ◽  
Exchange Reaction ◽  
Anion Exchange ◽  
Exchange Resin ◽  
Anion Exchange Resin ◽  
Equilibrium Constants ◽  
Exchange Reactions ◽  
Ion Exchange Reaction ◽  
Industrial Grade ◽  
Bromide Ions

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.

scholarly journals Thermodynamics of Ion-Exchange Reaction in Predicting the Ionic Selectivity of Auchlite ARA-9366 and Auchlite A-378 Anion Exchange Resins

2014 ◽  
Vol 25 ◽  
pp. 1-7 ◽  
Author(s):  
P.U. Singare ◽  
A.N. Patange
Keyword(s):  
Ion Exchange ◽  
Exchange Reaction ◽  
Anion Exchange ◽  
Ion Selectivity ◽  
Exchange Reactions ◽  
Ionic Selectivity ◽  
Iodide Ions ◽  
Ion Exchange Reaction ◽  
Anion Exchange Resins ◽  
Exchange Resins

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.

DFT study on MgAl-layered double hydroxides with different interlayer anions: structure, anion exchange, host–guest interaction and basic sites

2020 ◽  
Vol 22 (4) ◽  
pp. 2521-2529 ◽  
Author(s):  
Hui-Min Liu ◽  
Xiao-Jie Zhao ◽  
Yu-Quan Zhu ◽  
Hong Yan
Keyword(s):  
Anion Exchange ◽  
Layered Double Hydroxide ◽  
Layered Double Hydroxides ◽  
Functional Materials ◽  
Dft Study ◽  
Basic Sites ◽  
Double Hydroxide ◽  
Double Hydroxides

The guest anions play a key role in the construction of layered double hydroxide (LDH)-based host–guest functional materials.

scholarly journals Study on Halide Ions Selectivity of Nuclear Grade Anion Exchange Resin Auchlite ARA-9366

2014 ◽  
Vol 30 ◽  
pp. 67-73
Author(s):  
P.U. Singare ◽  
A.N. Patange
Keyword(s):  
Ion Exchange ◽  
Exchange Reaction ◽  
Anion Exchange ◽  
Exchange Resin ◽  
Anion Exchange Resin ◽  
Equilibrium Constants ◽  
Nuclear Grade ◽  
Exchange Reactions ◽  
Ion Exchange Reaction ◽  
Bromide Ions

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.

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