Selective adsorption of Pd(II) over Ag(I) in nitric acid solutions using nitrogen-donor-type adsorbents

Suzuki, Tomoya*; Otsubo, Ukyo*; Ogata, Takeshi*; Shiwaku, Hideaki; Kobayashi, Toru; Yaita, Tsuyoshi; Matsuoka, Mitsuaki*; Murayama, Norihiro*; Narita, Hirokazu*

Separation and Purification Technology, 308, p.122943_1 - 122943_7, 2023/03

https://doi.org/10.1016/j.seppur.2022.122943

HNO leaching is used in recycling Pd metal from spent products that primarily contain Ag, and most Pd residues are separated from solutions containing Ag(I). However, a small amount of Pd(II) often remains in these Ag(I) solutions. Therefore, the separation of Pd(II) and Ag(I) in HNO solutions is essential to promote efficient Pd recycling. In this study, the separation of Pd(II) and Ag(I) in HNO solutions was investigated using four N-donor-type adsorbents functionalized with amine (R-Amine), iminodiacetic acid (R-IDA), pyridine (R-Py), or bis-picolylamine (R-BPA). R-Amine, R-IDA, and R-Py selectively adsorbed Pd(II) over Ag(I), Cu(II), Ni(II), and Fe(III) from HNO solutions (0.3-7 M), but R-Amine exhibited a lower Pd adsorption efficiency. In contrast, 90% of Pd(II), Ag(I), and Cu(II) were adsorbed by R-BPA over the entire range of HNO concentrations. Structural analyses of the adsorbed metal ions using Fourier transform infrared spectroscopy and extended X-ray absorption fine structure spectroscopy revealed the separation mechanisms of the N-donor-type adsorbents. Pd(II) adsorption on R-IDA, R-Py, and R-BPA occurred via Pd(II) coordination of the functional groups (iminodiacetic acid, pyridine, and bis-picolylamine, respectively), whereas that on R-Amine occurred via anion exchange of NO with [Pd(NO)]. The coordinative adsorption mechanisms resulted in the higher Pd(II) adsorption behaviors of R-IDA, R-Py, and R-BPA. HCl (5.0 M) and thiourea (0.1 M) eluents desorbed 83% of Pd(II) from R-IDA and 95% from R-Py, respectively. R-Py was the most effective Pd(II) adsorbent based on adsorption selectivity and desorption efficiency.

New precise measurements of muonium hyperfine structure at J-PARC MUSE

Strasser, P.*; Abe, Mitsushi*; Aoki, Masaharu*; Choi, S.*; Fukao, Yoshinori*; Higashi, Yoshitaka*; Higuchi, Takashi*; Iinuma, Hiromi*; Ikedo, Yutaka*; Ishida, Katsuhiko*; et al.

EPJ Web of Conferences, 198, p.00003_1 - 00003_8, 2019/01

https://doi.org/10.1051/epjconf/201919800003

Mechanism of state-specific enhancement in photon-stimulated desorption as studied using a polarization-dependent technique

Sekiguchi, Tetsuhiro; Baba, Yuji; Shimoyama, Iwao; Wu, G.*; Kitajima, Yoshinori*

Surface Science, 593(1-3), p.310 - 317, 2005/11

https://doi.org/10.1016/j.susc.2005.06.076

Using a newly developed rotatable time-of-flight mass spectrometer(R-TOF-MS) and polarized synchrotron radiation, orientation effect on fragmentation and desorption pathways occurring at the top-most layers of molecular solids have been investigated. Reported will be polarization-angle dependencies of TOF mass spectra, high-resolution electron- and ion-NEXAFS in condensed chlorobenzene.

Substitution effect on orientation of organosilicon compounds (CH)SiX (X = F, Cl, Br, I, NCO) as studied using NEXAFS spectroscopy

Sekiguchi, Tetsuhiro; Baba, Yuji; Shimoyama, Iwao; Nath, K. G.*; Uddin, M. N.*

Journal of Physics; Condensed Matter, 17(36), p.5453 - 5466, 2005/09

https://doi.org/10.1088/0953-8984/17/36/002

The orientation nature of multilayer organosilicon compounds has been investigated by measuring the dependence of the Si K-shell near-edge X-ray absorption fine structures (NEXAFS) on the polarization angle. Two approaches helped to elucidate the orientation mechanism: the substitution effect and the deposition-rate dependence. The orientation angles of Si-X bond axes were obtained for trimethylsilyl halides, (CH)SiX (X =F Cl Br I NCO, condensed on Cu(111) at a low (82 K) temperature: the angles are 60, 73, 61, 55, and 55 degrees with respect to the surface normal, for X =F, Cl, Br, I, and NCO, respectively. Chloride (X =Cl) produces the most parallel tilt angle. The specific orientation nature of chloride is attributed to its strong dipole moment as well as the regular tetrahedron shape of the molecule. The molecular volumes calculated verify this view. Furthermore, deposition rates are found to greatly influence the growth manner: namely, high deposition rates led to a slightly perpendicular orientation of Si-X bond axis.

Fragment-ion desorption from sulfur-containing amino acids by localized core-level excitation

Baba, Yuji; Sekiguchi, Tetsuhiro; Shimoyama, Iwao

Surface Review and Letters, 9(1), p.77 - 83, 2002/02

https://doi.org/10.1142/S0218625X02002130

no abstracts in English

Symmetries of compound systems revealed in the superfine structure of neutron resonance levels

Ideno, K.

Proc. of Int. Conf. on Neutrons in Research and Industry, 2867, p.398 - 403, 1996/06

no abstracts in English

High-resolution neutron powder diffraction study of DyFeAl at 65K

S.Ridwan*; H.Mujamilah*; M.Gunawan*; P.Marsongkohadi*; Q.W.Yan*; P.L.Zhang*; X.D.Sun*; Z.H.Cheng*; Minakawa, Nobuaki; *

Journal of the Physical Society of Japan, 65(2), p.348 - 350, 1996/02

https://doi.org/10.1143/JPSJ.65.348

no abstracts in English

Effect of hyperfine structure on multiple photo-ionization of atom

Akaoka, Katsuaki; Oba, Masaki; Wakaida, Ikuo; Miyabe, Masabumi; Arisawa, Takashi

Laser Advanced Materials Processing,Vol. 2, p.1233 - 1237, 1992/06

no abstracts in English

Measurement of hyperfine structure of the 4f5d G-4f6pH in PrII by collinear laser-ion-beam spectroscopy

; Nakahara, Yoshinori; ; *; *; *

Journal of the Physical Society of Japan, 59(12), p.4208 - 4210, 1990/12

https://doi.org/10.1143/JPSJ.59.4208

no abstracts in English

The Fine structure of graft polyethylene

Sasuga, Tsuneo; Araki, Kunio; ; Kuriyama, Isamu

Reports on Progress in Polymer Physics in Japan, 15, p.515 - 518, 1972/00

no abstracts in English