Kinetic analysis of mass transfer of Eu(III) in extractant-impregnated polymer-layered silica particle in multiple-ion distribution system

Miyagawa, Akihisa*; Hayashi, Naoki*; Iwamoto, Hibiki*; Arai, Tsuyoshi*; Nagatomo, Shigenori*; Miyazaki, Yasunori; Hasegawa, Kenta; Sano, Yuichi; Nakatani, Kiyoharu*

Analytical Sciences, 40(2), p.347 - 352, 2024/02

https://doi.org/10.1007/s44211-023-00462-x

The Eu(III) distribution mechanism in single extractant-impregnated polymer-layered silica particle in a complex solution containing multiple lanthanide ions was investigated using fluorescence microspectroscopy. The rate-determining step was the reaction of Eu(III) with the two extractant molecules. The obtained mechanism and rate constants agreed with those of the single-ion distribution system, in which Eu(III) was distributed to the particles in the Eu(III) solution.

Competitive distribution of europium and samarium based on reaction rate-limiting process in nitrilotriacetamide extractant-impregnated polymer-coated silica particles

Miyagawa, Akihisa*; Hayashi, Naoki*; Iwamoto, Hibiki*; Arai, Tsuyoshi*; Nagatomo, Shigenori*; Miyazaki, Yasunori; Hasegawa, Kenta; Sano, Yuichi; Nakatani, Kiyoharu*

Bulletin of the Chemical Society of Japan, 96(9), p.1019 - 1025, 2023/09

https://doi.org/10.1246/bcsj.20230142

In the present study, we have elucidated the mass transfer mechanism of Eu(III) and Sm(III) in the solution with these ions in single nitrilotriacetamide (NTA) extractant-impregnated polymer-coated silica particle. The rate-limiting process of mass transfer was the reaction process of ions with NTA molecules, in which the NO ions were not involved, which was consistent with that obtained in single ion distribution system.

Combining a lipophilic phenanthroline carboxamide and a hydrophilic diglycolamide to increase the separation factors of adjacent light lanthanides

Simonnet, M.; Sasaki, Yuji; Yaita, Tsuyoshi

Solvent Extraction and Ion Exchange, 41(7), p.857 - 867, 2023/00

https://doi.org/10.1080/07366299.2023.2248189

Separation of light and middle lanthanides using multistage extraction with diglycolamide extractant

Matsutani, Takafumi; Sasaki, Yuji; Katsuta, Shoichi*

Analytical Sciences, 37(11), p.1603 - 1609, 2021/11

https://doi.org/10.2116/analsci.21P120

We investigated the chemical behavior of lanthanides (Ln) using diglycolamide extractant with multistage extraction. We obtained the breakthrough curves for light and middle Ln. Our study reveals that the metal extraction limit depends on their values and metal concentrations used in the experiments. From the multistage extractions of 15 aqueous phases and 15 organic phases, three curves (extraction curves, back-extraction curves, and separation curves) were obtained by changing the nitric acid concentration. As an example, under a condition of the separation curve experiment (aqueous phase: 0.5 M HNO, organic phase: 0.1 M TDDGA (-tetradecyl-diglycolamide) in -dodecane), a recovery of more than 99% of Sm in the organic phase with less than 1% Nd can be obtained.

Lanthanide intra-series separation by a 1,10-phenanthroline derivative; Counterion effect

Simonnet, M.; Suzuki, Shinichi; Miyazaki, Yuji*; Kobayashi, Toru; Yokoyama, Keiichi; Yaita, Tsuyoshi

Solvent Extraction and Ion Exchange, 38(4), p.430 - 440, 2020/00

https://doi.org/10.1080/07366299.2020.1744806

Stability of lanthanide oxides in LiCl-KCl eutectic melt

Hayashi, Hirokazu; Minato, Kazuo

Journal of Physics and Chemistry of Solids, 66(2-4), p.422 - 426, 2005/02

https://doi.org/10.1016/j.jpcs.2004.06.054

Stability of lanthanide sesquioxides (LnO; Ln=La, Nd, Gd) in LiCl-KCl eutectic melt is studied. Some lanthanide oxides have been pointed out to form oxide chlorides (LnOCl) in the chloride melts, according to the reaction, LnO + 2Cl = 2LnOCl +O. Equilibrium of the reaction for Ln = La, Nd, Gd in LiCl-KCl eutectic melt were studied. Entire LaO and a part of NdO converted to LaOCl and NdOCl respectively, though GdO remained with a trace amount of GdOCl for 2wt % of LnO in LiCl-KCl eutectic melt. The equilibrium depends on the free energies of formation of the solid compounds, LnO and LnOCl, and that of oxide ion (O) in the melt. We derive the chemical potential of the oxide ion from the equilibrium using the reported thermochemical data of LnO and LnOCl.

Rare earth element distribution in the acetic acid soluble fraction of combusted coals; Its implication as a proxy for the original coal-forming plants

Fu, F.; Akagi, Tasuku*; Suzuki, Yuichiro*; Watanabe, Kazuo; Yabuki, Sadayo*

Geochemical Journal, 38(4), p.333 - 343, 2004/08

https://doi.org/10.2343/geochemj.38.333

no abstracts in English

Extraction studies of lanthanide(III) ions with -dimethyl--diphenylpyridine-2,6-dicarboxyamide(DMDPhPDA) from nitric acid solutions

Shimada, Asako; Yaita, Tsuyoshi; Narita, Hirokazu; Tachimori, Shoichi; Okuno, Kenji*

Solvent Extraction and Ion Exchange, 22(2), p.147 - 161, 2004/03

https://doi.org/10.1081/SEI-120030392

The distribution ratios of lanthanides with -dimethyl--diphenylpyridine-2,6-dicarboxyamide(DMDPhPDA) from 1-5M nitric acid solutions were determined and the extraction mechanism was discussed on the basis of the slope analyses of acid and ligand concentration dependencies and lanthanide patterns (variation of the distribution ratio as a function of ionic radius). The lanthanide extractions were explained through two mechanisms from the standpoint of the formation of the extracted complex as follows: (1) the formation of inner-sphere complex with two DMDPhPDA molecules for light lanthanides in the extraction from HNO less than 3M, and (2) the formation of outer-sphere complex with the third DMDPhPDA molecules in addition to the inner-sphere complex in the extraction of light lanthanides from HNO more than 3M, and those of heavy lanthanides from 1-5M HNO solutions. Nitric acid concentration is more influential than the ligand concentration in the formation of outer-sphere complex.

Structural study on lanthanide complexes with tridentate ligands in solution

Narita, Hirokazu; Yaita, Tsuyoshi; Okamoto, Yoshihiro; Takai, Konomi; Shiwaku, Hideaki; Shimada, Asako*; Yamamoto, Takeshi*; Tanida, Hajime*

Spring-8 Experiment Report, Vol.6, P. 9, 2001/00

no abstracts in English

Application of centrifugal partition chromatography to separation of actinides and lanthanides in TBP extraction system

Usuda, Shigekazu; Abe, Hitoshi; Tachimori, Shoichi; Takeishi, Hideyo;

Solvent Extraction 1990, p.717 - 722, 1992/00

no abstracts in English