Microbially formed Mn(IV) oxide as a novel adsorbent for removal of Radium

Tanaka, Kazuya; Yamaji, Keiko*; Masuya, Hayato*; Tomita, Jumpei; Ozawa, Mayumi*; Yamasaki, Shinya*; Tokunaga, Kohei; Fukuyama, Kenjin*; Ohara, Yoshiyuki*; Maamoun, I.*; et al.

Chemosphere, 355, p.141837_1 - 141837_11, 2024/05

https://doi.org/10.1016/j.chemosphere.2024.141837

In this study, biogenic Mn(IV) oxide was applied to remove Ra from mine water collected from a U mill tailings pond in the Ningyo-toge center. Just 7.6 mg of biogenic Mn(IV) oxide removed more than 98% of the Ra from 3 L of mine water, corresponding to a distribution coefficient of 10 mL/g for Ra at pH 7. The obtained value was convincingly high for practical application of biogenic Mn(IV) oxide in water treatment.

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.

An Analytical method of low-level radium isotopes in freshwater sample by -ray spectrometry; Application of pre-concentration from large volume of water sample using Powdex resin and barium sulfate coprecipitation of radium isotopes

Tomita, Jumpei; Abe, Takuya

JAEA-Research 2016-026, 12 Pages, 2017/03

JAEA-Research-2016-026.pdf:1.15MB

An analytical method of low-level Ra isotopes in freshwater samples with combination of pre-concentration from large volume of water sample (170 L) using Powdex resin and -ray spectrometry followed by simple coprecipitation of Ra was developed. pre-concentration of Ra by batch method using Powder resin was examined, and it was shown that the amount of the resin required collecting Ra in the water sample could be determined by measuring the electric conductivity (EC) of water sample. It was found that coprecipitation of Ra with barium sulfate could remove more than 96% of potassium that increases the background. The validation of this method was confirmed by the analyses of 170 L of water sample containing the known amount of Ra isotopes with different EC. Among the analyses, the recovery of Ra was 98% in average and detection limits of Ra and Ra were achieved to be approximately 0.3 and 0.5 mBq L, respectively.

CO adsorption and decomposition on Pd/AlO studied by time-resolved XAFS using dispersive optics

Matsumura, Daiju; Okajima, Yuka*; Nishihata, Yasuo

Journal of Physics; Conference Series, 712(1), p.012042_1 - 012042_4, 2016/06

https://doi.org/10.1088/1742-6596/712/1/012042

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.