The extraction of selected M(III) metals by bis 2-ethylhexyl phosphoric acid in n-heptane

Mason, G.W.; Metta, D.N.; Peppard, D.F.

doi:10.1016/0022-1902(76)80472-1

Cited by 42 publications

(8 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Normalizing to the water solution, the relative free energies of n -dodecane and biphasic solvents were found to be favored with values of −9 ± 5 and −8.6 ± 0.6 kcal/mol, respectively. In addition, it was observed that the free energies between n -dodecane and biphasic solvent were similar (difference of 0.4 kcal/mol), which was expected as it is well known that HEHEHP is soluble in both n -dodecane and biphasic solvent. − ,− − ,− As the experimental observations of favorable and unfavorable interactions of HEHEHP with the organic and aqueous phases, respectively, are reflected, it is believed that the energies calculated through TI are quantitatively representative of the HEHEHP ligand.…”

Section: Resultsmentioning

confidence: 64%

“…To quantify ligand–ligand aggregation in the MD simulations, cluster analysis was performed on HEHEHP within different solvents. It is well known that HEHEHP, when coordinating with a metal cation, forms dimer clusters between the head groups in an organic phase. − Therefore, to investigate whether the MD simulations can reproduce the same behavior, cluster analysis was conducted in the absence of metal cations. A cluster was considered to be formed if phosphorous atoms of different ligand molecules came within a cutoff distance of 4.9 Å.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Solvation Dynamics of HEHEHP Ligand at the Liquid–Liquid Interface

Hegde

Etz

et al. 2018

J. Phys. Chem. B

View full text Add to dashboard Cite

Actinide-lanthanide separation (ALSEP) has been a topic of interest in recent years as it has been shown to selectively extract problematic metals from spent nuclear fuel. However, the process suffers from slow kinetics, prohibiting it from being applied to nuclear facilities. In an effort to improve the process, many fundamental studies have been performed, but the majority have only focused on the thermodynamics of separation. Therefore, to understand the mechanism behind the ALSEP process, molecular dynamics (MD) simulations were utilized to obtain the dynamics and solvation characteristics for an organic extractant, 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (HEHEHP). Simulations were conducted with both pure and biphasic solvent systems to evaluate the complex solvent interactions within the ALSEP extraction method. The MD simulations revealed solvation and dynamical behaviors that are consistent with the experimentally observed chemical properties of HEHEHP for the pure solvent systems (e.g., hydrophobic/hydrophilic behaviors of the polar head group and alkyl chains and dimer formation between the ligands within an organic solvent). When present in a biphasic solvent system, interfacial behaviors of the ligand revealed that, at low concentrations, the alkyl side chains of HEHEHP were parallel to the interfacial plane. Upon increasing the concentration to 0.75 M, tendency for the parallel orientation decreased and a more perpendicular-like orientation was observed. Analysis of ligand solvation energies in different solvents through the thermodynamic integration method demonstrated favorability toward n-dodecane and biphasic solvents, which is in agreement with the previous experimental findings.

show abstract

Section: Resultsmentioning

confidence: 64%

Section: Resultsmentioning

confidence: 99%

Solvation Dynamics of HEHEHP Ligand at the Liquid–Liquid Interface

Hegde

Etz

et al. 2018

J. Phys. Chem. B

View full text Add to dashboard Cite

show abstract

“…Up to now, there are many acidic organophosphorous extractants, − neutral organophosphorous extractants, − and amine extractants, which are used for RE separation in hydrochloric acid, nitrate acid, or sulfuric acid systems. The extraction property and separation sequence was influenced by the extractant and different medium.…”

Section: Introductionmentioning

confidence: 99%

Highly Selective Extraction and Separation of Rare Earths(III) Using Bifunctional Ionic Liquid Extractant

Guo

Chen

Shen

et al. 2014

ACS Sustainable Chem. Eng.

View full text Add to dashboard Cite

The extraction and separation of rare earths (REs) from nitrate medium or chloride medium using bifunctional ionic liquid extractants (Bif-ILEs) [trialkylmethylammonium][di(2-ethylhexyl)orthophosphinate] ([A336][P507]) and [trialkylmethylammonium][di-2-ethylhexylphosphate] ([A336][P204]) in n-heptane were investigated in this report. The separation factor (β) values indicated that [A336][P507] and [A336][P204] could be suitable for the separation of heavy REs(III) in nitrate medium and suitable for the separation of light REs(III) in chloride medium. Especially, in nitrate medium, the β values using [A336][P204] as the extractant were Tm/Er (3.36), Yb/Tm (7.92), and Lu/Yb (8.55), respectively, and in chloride medium, the β values using [A336][P507] as the extractant were Nd/Pr (9.52) and Sm/Nd (4.70), respectively. The β̅ z+1/z values of REs(III) extracted by [A336][P507] and [A336][P204] in nitrate medium were 3.61 and 3.67, respectively, and in chloride medium, they were 2.75 and 2.59, respectively.

show abstract

“…Zikovsky studied the effect of diluents on REEs extraction with D2EHPA and reported that the recovery was enhanced according to the following order of diluents: heptane, cyclohexane, butyl ether, carbon tetrachloride, toluene, xylene, nitrobenzene, bromoform, chlorobenzene, benzene, hexane, dichloromethane, and chloroform . REEs extraction by D2EHPA was investigated in the presence of various mineral acids in such organic diluents as n -heptane, − kerosene, − benzene, − n -dodecane, − Amsco, − hexane, and toluene. ,− …”

Section: Introductionmentioning

confidence: 99%

“…With the thermodynamic characteristics of REE complexation and/or extraction, authors usually determined concentration equilibrium constants instead of thermodynamic constants. In this case equilibrium is studied in the presence of a buffer for used to retain a constant pH value or ionic strength. ,, The aforementioned data can be used to validate existing models of the extraction processes. However, this is not enough for calculating the interaction parameters of the components and developing new thermodynamic models, which are necessary for the optimization of the present methods and developing the alternative techniques for the recovery and separation of REEs.…”

Section: Introductionmentioning

confidence: 99%

Liquid–Liquid Equilibria in Multicomponent Systems Containing o-Xylene, Di-(2-ethylhexyl)phosphoric Acid, Water, Nitric Acid, and Europium (Gadolinium, Dysprosium) Nitrate at 298.15 K

et al. 2017

View full text Add to dashboard Cite

The extraction of europium(III), dysprosium(III), and gadolinium(III) nitrates with di-(2-ethylhexyl) phosphoric acid (D2EHPA) in o-xylene was investigated at 298.15 K. Spectrophotometry and ICP-AES techniques were used for rare earth elements (REE) content determination. The content of nitric acid was measured by acid–base titration. The density of the equilibrium phases was determined. In the case of high content of rare earth element nitrates in the initial aqueous solutions, the third solid phase formation was observed during extraction experiments.

show abstract

The extraction of selected M(III) metals by bis 2-ethylhexyl phosphoric acid in n-heptane

Cited by 42 publications

References 6 publications

Solvation Dynamics of HEHEHP Ligand at the Liquid–Liquid Interface

Solvation Dynamics of HEHEHP Ligand at the Liquid–Liquid Interface

Highly Selective Extraction and Separation of Rare Earths(III) Using Bifunctional Ionic Liquid Extractant

Liquid–Liquid Equilibria in Multicomponent Systems Containing o-Xylene, Di-(2-ethylhexyl)phosphoric Acid, Water, Nitric Acid, and Europium (Gadolinium, Dysprosium) Nitrate at 298.15 K

Contact Info

Product

Resources

About