Related Experiment Video
Updated: Aug 27, 2025
10:14
Synthesis and Purification of Iodoaziridines Involving Quantitative Selection of the Optimal Stationary Phase for Chromatography
Published on: May 16, 2014
12.6K
Iodine speciation in deep eutectic solvents
Jennifer M Hartley1, Sean Scott1, Zarfishan Dilruba1
1School of Chemistry, University of Leicester, Leicester, LE1 7RH, UK. jmh84@le.ac.uk.
Physical Chemistry Chemical Physics : PCCP
|September 30, 2022
Summary
Iodine speciation in deep eutectic solvents (DESs) was investigated, revealing distinct iodine species (I2Cl-, I3-, and I2) dependent on the hydrogen bond donor. Metal oxidation correlated with these species and solvent properties.
Area of Science:
- Analytical Chemistry
- Electrochemistry
- Materials Science
Background:
- Iodine acts as an electrocatalyst for metal digestion in deep eutectic solvents (DESs).
- Limited understanding exists regarding iodine speciation and reactivity in high-chloride DES media.
Purpose of the Study:
- To investigate iodine speciation in various DESs with different hydrogen bond donors (HBDs).
- To examine the effect of iodine concentration on speciation.
- To correlate metal oxidation with iodine speciation and HBD properties.
Main Methods:
- Extended X-ray absorption fine structure (EXAFS) spectroscopy at the iodine K-edge.
- UV-vis spectroscopy for speciation confirmation.
- Electrochemical measurements.
- Metal leaching experiments.
Main Results:
- Three distinct iodine speciation groups were identified: mixed I2Cl-/I3- (glycol, lactic acid), mixed I3-/I2 (oxalic acid, urea), and singular I3- (levulinic acid).
- Iodine concentration (0.01–0.5 mol dm-3) influenced speciation.
- Iodine redox behavior remained consistent across different speciation states.
- Metal oxidation was influenced by iodine speciation, HBD reactivity, and coordination ability.
Conclusions:
- Iodine speciation in DESs is highly dependent on the choice of hydrogen bond donor.
- Metal digestion efficiency is a complex interplay between iodine speciation and the solvent's chemical environment.
- EXAFS and UV-vis spectroscopy are effective tools for characterizing iodine speciation in DESs.
More Related Videos
Related Concept Videos
03:11Precipitation of Ions
28.1K
Predicting Precipitation
The equation that describes the equilibrium between solid calcium carbonate and its solvated ions is:
The equation that describes the equilibrium between solid calcium carbonate and its solvated ions is:
28.1K
01:09Ion-Exchange Chromatography
671
Ion-exchange chromatography, or IEC, is a technique for separating ions based on their affinity for the stationary phase. The stationary phase is a cross-linked polymer resin with covalently attached ionic functional groups. The functional groups can be either positively charged (cation exchangers) or negatively charged (anion exchangers). A cation exchanger consists of a polymeric anion and active cations, while an anion exchanger is a polymeric cation with active anions. The choice of...
671
02:16Solution Formation
32.4K
There is no one solvent that can dissolve every type of solute. Some substances that readily dissolve in a certain solvent might be insoluble in a different solvent. A simple way to predict which substances dissolve in which solvent is the phrase "like dissolves like". This means that polar substances, such as salt and sugar, dissolve in a polar substance like water. In contrast, non-polar substances are more soluble in non-polar solvents such as carbon tetrachloride.
This selective...
This selective...
32.4K
00:56Extraction: Advanced Methods
510
Metal ions can be separated from one another by complexation with organic ligands–the chelating agent– to form uncharged chelates. Here, the chelating agent must contain hydrophobic groups and behave as a weak acid, losing a proton to bind with the metal. Since most organic ligands used in this process are insoluble or undergo oxidation in the aqueous phase, the chelating agent is initially added to the organic phase and extracted into the aqueous phase. The metal-ligand complex is...
510
01:23Redox Titration: Iodimetry and Iodometry
2.4K
Iodometry and iodimetry are analytical methods used to determine the concentration of oxidizing or reducing agents using iodine. In iodometric titrations, the oxidizing analyte solution is usually acidified and treated with an excess of iodide ions, which generates an equivalent amount of iodine in equilibrium with triiodide. The released iodine is subsequently titrated directly against a standardized reducing agent. As the dilute iodine color becomes pale yellow, a few drops of freshly...
2.4K
02:55Solubility of Ionic Compounds
63.8K
Solubility is the measure of the maximum amount of solute that can be dissolved in a given quantity of solvent at a given temperature and pressure. Solubility is usually measured in molarity (M) or moles per liter (mol/L). A compound is termed soluble if it dissolves in water.
63.8K