Organization of malonamides from the interface to the organic bulk phase

Micheau, C.; Ueda, Yuki; Motokawa, Ryuhei; Akutsu, Kazuhiro*; Yamada, Norifumi*; Yamada, Masako*; Moussaoui, S. A.*; Makombe, E.*; Meyer, D.*; Berthon, L.*; et al.

Journal of Molecular Liquids, 401, p.124372_1 - 124372_12, 2024/05

https://doi.org/10.1016/j.molliq.2024.124372

Supramolecular organization of extractant molecules impacts metal ions separation behavior. Probing bulk and interfacial structures of the relevant systems is expected to provide key insights into the metal ion selectivity and kinetic aspects. The supramolecular features of two solvent extraction systems based on malonamide extractants THMA in toluene and DBMA in n-heptane were studied using small-angle X-ray scattering for the organic bulk phases, as well as interfacial tension and neutron reflectivity measurements for the interfaces. In the bulk solution, THMA forms dimeric/trimeric associates but no aggregates in toluene, while DBMA forms large aggregates in n-heptane. On the other hand, THMA accumulates in a diffuse layer at the interface at high THMA concentration, whereas DBMA forms a compact but thinner layer. After Pd(II) extraction, the thickness of interfacial layers decreases in the case of THMA, and totally vanishes in the case of DBMA. Based on these new structural information, two mechanisms are proposed for Pd(II) and Nd(III) extraction with malonamides. In toluene, THMA associates slightly accumulate in the vicinity of the interface, then coordinate Pd(II) and diffuse into the organic bulk phase. In n-heptane, DBMA aggregates adsorb at the interface then pick up Nd(III) cations in their polar cores and finally diffuse into the bulk.

Foam flotation of clay particles using a bifunctional amine surfactant

Micheau, C.; Ueda, Yuki; Motokawa, Ryuhei; Bauduin, P.*; Girard, L.*; Diat, O.*

Langmuir, 39(31), p.10965 - 10977, 2023/07

https://doi.org/10.1021/acs.langmuir.3c01213

Deuterated malonamide synthesis for fundamental research on solvent extraction systems

Micheau, C.; Ueda, Yuki; Akutsu, Kazuhiro*; Bourgeois, D.*; Motokawa, Ryuhei

Solvent Extraction and Ion Exchange, 41(2), p.221 - 240, 2023/02

https://doi.org/10.1080/07366299.2023.2166351

Urea-introduced ionic liquid for the effective extraction of Pt(IV) and Pd(II) ions

Ueda, Yuki; Eguchi, Ayano; Tokunaga, Kohei; Kikuchi, Kei*; Sugita, Tsuyoshi; Okamura, Hiroyuki; Naganawa, Hirochika

Industrial & Engineering Chemistry Research, 61(19), p.6640 - 6649, 2022/05

https://doi.org/10.1021/acs.iecr.2c00304

no abstracts in English

Effective extraction of Pt(IV) as [PtCl] from hydrochloric acid using a simple urea extractant

Ueda, Yuki; Morisada, Shintaro*; Kawakita, Hidetaka*; Wenzel, M.*; Weigand, J. J.*; Oto, Keisuke*

Separation and Purification Technology, 277, p.119456_1 - 119456_8, 2021/12

https://doi.org/10.1016/j.seppur.2021.119456

no abstracts in English

Polarization analysis for small-angle neutron scattering with a He spin filter at a pulsed neutron source

Okudaira, Takuya; Ueda, Yuki; Hiroi, Kosuke; Motokawa, Ryuhei; Inamura, Yasuhiro; Takata, Shinichi; Oku, Takayuki; Suzuki, Junichi*; Takahashi, Shingo*; Endo, Hitoshi*; et al.

Journal of Applied Crystallography, 54(2), p.548 - 556, 2021/04

https://doi.org/10.1107/S1600576721001643

Neutron polarization analysis (NPA) for small-angle neutron scattering (SANS) experiments using a pulsed neutron source was successfully achieved by applying a He spin filter as a spin analyzer for the scattered neutrons. The He spin filter covers a sufficient solid angle for performing SANS experiments, and the relaxation time of the He polarization is sufficient for continuous use over a few days, thus reaching the typical duration required for a complete set of SANS experiments. Although accurate evaluation of the incoherent neutron scattering, which is predominantly attributable to hydrogen atoms in samples, is practically difficult using calculations based on the sample elemental composition, the developed NPA approach with consideration of the influence of multiple neutron scattering enabled reliable decomposition of the SANS intensity distribution into the coherent and incoherent scattering components. To date, NPA has not been well established as a standard technique for SANS experiments at pulsed neutron sources. This work is anticipated to greatly contribute to the accurate determination of the coherent neutron scattering component for scatterers in various types of organic sample systems in SANS experiments at J-PARC.

Extraction performance of a fluorous phosphate for Zr(IV) from HNO solution; Comparison with tri--butyl phosphate

Ueda, Yuki; Kikuchi, Kei; Sugita, Tsuyoshi; Motokawa, Ryuhei

Solvent Extraction and Ion Exchange, 37(5), p.347 - 359, 2019/07

https://doi.org/10.1080/07366299.2019.1638015

We have newly-designed fluorous phosphate(TFP) for the effective Zr(IV) ion extractant as an alternative extractant against the conventional organic phosphate, tri--butyl phosphate(TBP). Zr(IV) ion extraction system using the TBP has many problems such as the formation of the third phase during liquid-liquid extraction. Here, we develop the fluorous extraction system based on the TFP-perfluorohexane for the Zr(IV) ion extraction to improve the Zr(IV) ion extraction system with an effective extractability and without the third phase formation. Our main findings were that the significant high extraction performance of the TFP for Zr(IV) ion as compared with TBP, and the origins of the high extraction performance of the TFP are related to the water and HNO contents in the fluorous phase and the stability of the complex, Zr(No)(TFP).

Spectroscopic analysis for extraction of Pt(IV) with amide and urea type extractants

Ueda, Yuki; Sugita, Tsuyoshi; Okamura, Hiroyuki; Shimojo, Kojiro; Naganawa, Hirochika; Morisada, Shintaro*; Kawakita, Hidetaka*; Oto, Keisuke*

no journal, , 

Platinum group metals (PGMs) are indispensable metals in modern industries and are used for example as active components in automobile gas catalysts, jewellery goods, electronic devices and dental materials. In order to meet the growing demand, high efficient receptors for liquid-liquid extraction of the respective anionic chloro-complexes are required in order to enhance capable winning from either pour geological deposits or complex secondary sources within the Urban Mining. The ligand containing urea or amide groups can form the hydrogen bond with anionic species. The novel urea or amide containing extractants were synthesized and its extraction behavior and mechanism were investigated in this work.

Development of organophosphate amide type extractant and application to ionic liquid system

Sugita, Tsuyoshi; Okamura, Hiroyuki; Ueda, Yuki; Naganawa, Hirochika; Shimojo, Kojiro

no journal, , 

Ionic liquid extraction system has unique extraction property. In this study, novel organophosphate type neutral extractant with tridentate structure was synthesized and it's extraction ability and extraction mechanisms were revealed in ionic liquid system.

Extraction of trivalent lanthanoids into various ionic liquids having different anions

Eguchi, Ayano; Okamura, Hiroyuki; Sugita, Tsuyoshi; Ueda, Yuki; Morita, Kotaro*; Shimojo, Kojiro; Naganawa, Hirochika; Hirayama, Naoki*

no journal, , 

In this study, the effect of the hydrophobicity and structure of an ionic liquid (IL) anion on the extraction of trivalent lanthanoid ions (Ln(III) = La, Nd, Eu, Dy, Lu) using 2-thenoyltrifluoroacetone (Htta) was investigated. Four 1-butyl-3-methylimidazolium bis(perfluoroalkanesulfonyl)imides with different perfluoroalkyl (Rf) chain length (n=0, 1, 2, 4) were synthesized and used as the extraction solvent. The extraction selectivity of Ln(III) was in the order of Lu Dy Eu Nd La for all ILs. In addition, there was no significant difference in the extractability among ILs. The extracted species of each Ln(III) in these IL systems were investigated based on the slope of the plots of the logarithmic distribution ratio of Ln(III) as a function of aqueous phase pH. The results implied that the extracted species can be adjusted by Rf chain length of IL anions.