Synthesis and characterization of iodovanadinite using PdI, an iodine source for the immobilisation of radioiodine

Johnstone, E. V.*; Bailey, D. J.*; Lawson, S.*; Stennett, M. C.*; Corkhill, C. L.*; Kim, M.*; Heo, J.*; Matsumura, Daiju; Hyatt, N. C.*

RSC Advances (Internet), 10(42), p.25116 - 25124, 2020/07

https://doi.org/10.1039/D0RA04114A

Development of separation technique for platinum group metals from radioactive liquid waste utilizing laser-induced particulate formation

Saeki, Morihisa*; Asai, Shiho; Oba, Hironori*

Bunseki, 2018(4), p.138 - 143, 2018/04

Platinum group metal (PGM) has attracted much attention in light of increasing demands in the industrial sector. A wide variety of techniques specialized for PGM separation, such as, solvent extraction, solid phase extraction, and molten salt electrolysis have been developed so far. Among such techniques, a newly developed separation technique based on laser-induced particulate formation can be a promising alternative to conventional ones. It enables non-contact and highly-selective separation with a simple operation. In this review, the research history and the basic mechanism of laser-induced particulate formation were outlined. Several applications were also mentioned, focusing on our latest research progress which achieved a world first quantitation of radioactive palladium in a spent nuclear fuel sample.

Study on laser-induced particle formation of palladium ion by time-resolved X-ray spectroscopy

Saeki, Morihisa*; Taguchi, Tomitsugu*; Oba, Hironori*; Matsumura, Daiju; Tsuji, Takuya; Yomogida, Takumi

Denki Gakkai Kenkyukai Shiryo, Denshi Zairyo Kenkyukai (EFM-17-010021), p.15 - 18, 2017/09

Irradiation of nanosecond pulsed UV laser into a solution of palladium ion leads to formation of palladium particles with sub-micron size particles by time-resolved X-ray absorption spectroscopy.

X-ray absorption spectroscopy study on water formation reaction of palladium metal nanoparticle catalysts

Matsumura, Daiju; Taniguchi, Masashi*; Tanaka, Hirohisa*; Nishihata, Yasuo

International Journal of Hydrogen Energy, 42(11), p.7749 - 7754, 2017/03

https://doi.org/10.1016/j.ijhydene.2016.08.189

Effects of surface modification by ion irradiation on the electrochemical hydrogen absorption rate of Pd

Abe, Hiroshi; Morimoto, Ryo*; Sato, Fumiatsu*; Azuma, Yorito*; Uchida, Hirohisa*

Journal of Alloys and Compounds, 404-406, p.288 - 292, 2005/12

https://doi.org/10.1016/j.jallcom.2004.12.157

The effect of ion irradiation on the rate of electrochemical hydriding rate of palladium (Pd) was investigated. In this study, ion irradiation onto the Pd surface was made with H, He, Ar and N in the acceleration energy range from 30 to 350 keV, and in the ion dose up to 1 10 cm. As the ion dose was increased, the initial rate of hydriding of Pd was increased. The ion irradiatiion treatment of the surface of a metal induces high concentrations of vacancy. The increased hydriding rate may be caused by the induction of high concentration of vacancy whichi traps hydrogen atoms, and this seems to accelerate the rates of hydride nucleation and growth in the surface. The ion irradiation was found as an effective way to enhance the rate of the initial activation of Pd in the electrochemical hydriding process.

Solvent effect in supercritical carbon dioxide extraction of metal ions

Meguro, Yoshihiro; Ogiyanagi, Jin*; Tomioka, Osamu; Imura, Hisanori*; Ohashi, Kozaburo*; Yoshida, Zenko; Nakashima, Mikio

Proceedings of 2nd International Symposium on Supercritical Fluid Technology for Energy and Environment Applications (Super Green 2003), p.175 - 179, 2004/00

One of the most attractive properties of SFE is that changing solvent properties by tuning pressure can control distribution behavior of a metal ion. Distribution ratio (D) of uranium(VI) and plutonium(IV) with tributyl phosphate (TBP) from a nitric acid solution and palladium(II) with 2-methyl-8-qunolinol (HMQ) from a hydrochloric solution were determined in SFE at various pressures. In the extraction system using TBP, a linear relationship between the logarithmic distribution ratio (log D) and the solubility parameter of CO was observed. The solubility parameter is difined based on the regular solution theory and is one of the parameters depending on the pressure. On the other hand, a linear relationship with a positive slope between log D and the solubility parameter was observed in the extraction system using HMQ. Most of the extractant was dissolved in the aqueous phase as HMQ under the extraction condition examined.

Immortal catalytic activity for cleaning up automotive emissions; Intelligent catalyst

Nishihata, Yasuo; Tanaka, Hirohisa*

SPring-8 Riyosha Joho, 7(6), p.359 - 363, 2002/11

Catalytic converters are widely applied to control automotive emissions, such as nitrogen oxides, carbon monoxide and unburned hydrocarbons. In actual catalysts, however, the catalytic activity deteriorates due to the particle growth of precious metals during vehicle use. An ageless catalyst is a kind of philosopher's stone in automotive engineering. Referring to the wisdom of ancient Indian philosophy and medical science, Ayur Veda, we have developed a new self-regenerating perovskite-based catalyst. The perovskite catalyst, LaFeCoPdO, regenerates itself without any auxiliary treatment, in direct reaction to the natural fluctuation between reductive and oxidative atmospheres in the exhaust gas from state-of-the-art gasoline engines. As palladium reversibly moves back and forth between inside and outside of the perovskite crystal, the particle growth of palladium can be suppressed. Such a self-regeneration provides new insight into the development of future automotive catalyst, as an intelligent catalyst.

Radiation induced graft polymerization and its application to removal of toxic metals

Tamada, Masao

Hoshasen To Sangyo, (93), p.17 - 21, 2002/03

http://ci.nii.ac.jp/naid/40004433245

Radiation induced graft polymerization is useful technique for introducing aiming function into conventional polymers. Especially, preirradiation method can easily control the graft yield by irradiation dose and polymerization time. In this method, storing the irradiated polymer at low temperature is capable of grafting at discrete facility, which is merit for industrialization. Removal of toxic metals with grafted polymer needs the functions of ion exchange and chelating reaction. Graft polymerization is superior method to introduce such functions into the polymer. The fibrous adsorbent for lead ion, prepared by grafting, shows the high performance to the particle adsorbent.

Pseudomorphic growth of Pd monolayer on Au(111) electrode surface

Takahashi, Masamitsu; Hayashi, Yukio; Mizuki, Junichiro; Tamura, Kazuhisa*; Kondo, Toshihiro*; Naohara, Hideo*; Uosaki, Kohei*

Surface Science, 461(1-3), p.213 - 218, 2000/08

https://doi.org/10.1016/S0039-6028(00)00583-5

no abstracts in English

Sorption and Diffusion Behavior of Palladium in Bentonite, Granodiorite and Tuff

; ; Sato, Haruo; Shibata, Masahiro

JNC TN8400 99-088, 58 Pages, 1999/06

JNC-TN8400-99-088.pdf:3.87MB

Sorption and diffusion behavior of palladium, which has been identified as one of the hazardous radionuclides in performance assessment of HLW disposal, in bentonite, granodiorite and tuff was studied in order to make reliable data set for the performance assessment. Sorption experiments of Pd on bentonite, granodiorite and tuff were conducted as functions of pH, ionic strength and liquid to solid ratio by batch method under aerobic conditions at room temperature. The distribution coefficients (K) of Pd on these solids were almost in the range of 10 to 10 m/kg and were in the order of bentonite granodiorite tuff. The sorption trends with change in PH, ionic strength and liquid to solid ratio are very similar between three solids. The K values were the highest at pH5 and decreased with increasing pH between 5 and 11. The effect of ionic strength on K was not found in a range of 10 to 10, but K values increased with increasing liquid to solid ratio. The width of variation in K was one order of magnitude in a liquid to solid ratio of 0.1 to 1 m/kg. Sorption behavior of Pd is different from that of divalent metal ions such as Ni and Co etc. and chemical analogy may be inappropriate. The dominant aqueous species of Pd in the expermental conditions studied is estimated to be neutral species, Pd(OH)(aq) by the thermodynamic calculations. The K values of Pd on three solids were relatively high and uncharged complexes may be more strongly sorbed. The pH dependency of K values suggests that Pd sorption is most likely to be occurring onto positively charged S-OH type site which are progressively removed (to from SOH and SO sites) at higher pH values. Diffusion behavior of Pd in bentonite was also studied by in-diffusion method as a function of dry density. The D values obtained based on the instantaneous planar source model were in the orders of ...