Synergistic extraction of heavy rare earths by mixture of α-aminophosphonic acid HEHAMP and HEHEHP

Zhao, Qi; Li, Yanling; Kuang, Shengting; Zhang, Zhifeng; Bian, Xue; Liao, Wuping

doi:10.1016/j.jre.2018.07.013

Cited by 25 publications

(21 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Figure 3(a,b) depicts R in a secondary axis for two different scenarios. Figure 3(a) shows the extraction of Yb 3+ with HEHAMP and HEHEHP mixtures 39 . D mix in some molar ratios suppresses the distribution factor of HEHEHP in its pure form.…”

Section: Methodsmentioning

confidence: 99%

“…Synergistic factor for two different extractants, Yb 3+ (a) and Sm 3+ (b), when (a) both reagents extract the metal to some extent (organic phase: [HEHAMP] + [HEHEP] = 0.10 mol L –1 in heptane; aqueous phase: [Yb 3+ ] = 0.02 mol L –1 in hydrochloric media) 39 and (b) when one of the extractants has low extraction of the metal (organic phase: [Cyanex 301] + [D2EHPA] = 0.06 mol L –1 in kerosene; aqueous phase: [Sm 3+ ] = 0.005 mol L –1 in nitric media) 33 …”

Section: Methodsmentioning

confidence: 99%

“…Some report a sole value for a given extractant combination and metal such as R = 3.63 for La 3+ extraction with D2EHPA + CA12, 36 or R = 5.12 for Ho 3+ , 5.34 for Y 3+ , 7.04 for Er 3+ , 7.50 for Tm 3+ , 13.12 for Yb 3+ , and 17.58 for Lu 3+ with Cyanex 272 + CA12 37 . On many other occasions, extensive tables or figures with R values are reported depending on the concentration of the first extractant, implying extensive experimental procedures 20,33,38,39 . The heterogeneity found in the reported R value makes the task of comparison between extractants rather difficult.…”

Section: Introductionmentioning

confidence: 99%

“…37 On many other occasions, extensive tables or figures with R values are reported depending on the concentration of the first extractant, implying extensive experimental procedures. 20,33,38,39 The heterogeneity found in the reported R value makes the task of comparison between extractants rather difficult. Consequently, comparing the synergistic extractions is not possible with the current factor, indicating the need for the design of a new factor to compare future works properly.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Relative distribution enhancement: a new factor for the evaluation of synergistic solvent extraction

Gómez-Sánchez

Koga

Kim

et al. 2021

J of Chemical Tech & Biotech

View full text Add to dashboard Cite

BACKGROUND Solvent extraction is one of the most used processes worldwide for metal extraction at an industrial and laboratory scale. As a process that requires an external component, the selection of extractants is one of the most studied topics to find the most suitable ones for a particular case. The use of combined reagents, or so‐called synergistic extractants, is a branch of extraction studies that have proven better results than the use of solvents on their own. However, a comparison between synergistic extractants cannot be made with the currently reported factors. This paper provides a guide on clarifying the implications of the conventional synergistic factor, R, for the evaluation of the best extractant combinations. Moreover, a new indicator is proposed, named relative distribution enhancement factor, H, that will quantitatively measure the efficiency of the extraction and compare extraction enhancement among different experimental research. RESULTS Four references were selected to illustrate the use of the H factor in contrast with the R factor. The usefulness of the new enhancement factor H was demonstrated by evaluating the synergistic solvent extraction of rare earth elements. It was found that the use of R factors can mislead the selection of extractants ratio, and although synergism exists this does not imply an enhanced extraction. CONCLUSION The main finding of this work is that the newly developed H factor can easily detect extraction enhancement or diminishment and is not limited to the evaluation of two extractants. © 2021 Society of Chemical Industry (SCI).

show abstract

Section: Methodsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Relative distribution enhancement: a new factor for the evaluation of synergistic solvent extraction

Gómez-Sánchez

Koga

Kim

et al. 2021

J of Chemical Tech & Biotech

View full text Add to dashboard Cite

show abstract

“…EIPAs represent a large and diverse class of organophosphorus compounds, which are widely used as REE extractants due to their ability to form metal complexes. Di-(2-ethylhexyl) phosphoric acid (D2EHPA) and 2-ethylhexyl phosphoric acid mono-2-ethylhexyl ester (EHEHPA) are the most thoroughly studied among them [26][27][28][29]. Since REE are poorly stripped from D2EHPA complexes, EHEHPA is considered to be a perspective alternative with greater selectivity to REE and the possibility of stripping at lower acidities.…”

Section: Introductionmentioning

confidence: 99%

Linear 2-Ethylhexyl Imidophosphoric Esters as Effective Rare-Earth Element Extractants

Bredov¹,

Gorlov²,

Esin³

et al. 2020

Applied Sciences

View full text Add to dashboard Cite

Imidophosphoric organic esters containing phosphoryl groups are potential polydentate ligands and promising extractants of rare-earth elements. For their preparation, a monophosphazene salt [PCl3=N−PCl3]+[PCl6]− and short phosphazene oligomers of the general formula [Cl–(PCl2=N)n–PCl3]+[PCl6]−, where n = 4–7, were synthesized via living cationic polymerization of Cl3P=NSiMe3 and used as starting compounds. All phosphazenes were reacted with 2-ethylhexanol to obtain the corresponding esters of imidophosphoric acids (EIPAs). The formation of imidophosphoric acids occurs due to the phosphazene-phosphazane rearrangement of –P(OR)2=N– or –P(OH)(OR)=N– units, where R = 2-ethylhexyl. The prepared EIPAs were characterized by 1H, 31P NMR, and MALDI-TOF analyses and their extractive capacity towards lanthanide ions in aqueous solutions of nitric acid was examined. The EIPAs are mixtures of mono-, di-, and trifunctional compounds of the type HxA, where x = 1–3, which can form chelate complexes of lanthanide ions [Ln(A)z], where z = 3–6, depending on the chain length. The longer chain EIPAs are more suitable for collective rare-earth elements extraction. A comparison of the extraction properties of the EIPAs with the industrially used polyalkylphosphonitrilic acid (PAPNA) was drawn.

show abstract

Enhancing separation of Y(III) from Sr(II) using tributyl phosphate in a novel deep eutectic solvent media

Zhao,

Wu,

Shih

et al. 2024

AIChE Journal

View full text Add to dashboard Cite

A novel solvent extraction system was developed to separate Y3+ from Sr2+, where tributyl phosphate was chosen as an extractant and an organic solvent was a hydrophobic deep eutectic solvent (DES) consisting of oleic acid (OA) and 1‐butyl‐3‐methylimidazolium chloride ([BMIM]Cl). The extraction experiment demonstrated that the extraction system using OA‐[BMIM]Cl DES as an organic solvent exhibited great advantages of fast extraction and excellent selectivity for Y3+ (Y/Sr separation factor >500), which are hardly achieved in the extraction systems using conventional molecular solvent, for example, n‐heptane. Density functional theory calculations also confirmed that the Y/Sr separation is more thermodynamically favorable in OA‐[BMIM]Cl DES as an organic solvent compared to n‐heptane. An extraction process comprising two‐stage extraction, one‐stage scrubbing, and one‐stage stripping was proposed, achieving 95.06% of Y3+ selectively separated from a simulated solution and Y purity of 98.55% in the final product.

show abstract

Synergistic extraction of heavy rare earths by mixture of α-aminophosphonic acid HEHAMP and HEHEHP

Cited by 25 publications

References 19 publications

Relative distribution enhancement: a new factor for the evaluation of synergistic solvent extraction

Relative distribution enhancement: a new factor for the evaluation of synergistic solvent extraction

Linear 2-Ethylhexyl Imidophosphoric Esters as Effective Rare-Earth Element Extractants

Enhancing separation of Y(III) from Sr(II) using tributyl phosphate in a novel deep eutectic solvent media

Contact Info

Product

Resources

About