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Saiki, Seiichi; Puspitasari, T.*; Seko, Noriaki
Proceedings of 12th International Conference on Radiation Curing in Asia (RadTech Asia 2011) (Internet), p.124 - 125, 2011/06
Sawada, Shinichi; Iwai, Yasunori; Yamanishi, Toshihiko; Maekawa, Yasunari
Proceedings of 12th International Conference on Radiation Curing in Asia (RadTech Asia 2011) (Internet), p.242 - 243, 2011/06
In the polymer-electrolyte-membrane (PEM) water electrolysis system in the international thermonuclear experimental reactor (ITER), the PEM material with high radiation resistivity is required. In this study, we investigated the radiation degradation behavior of the PEMs synthesized by radiation grafting method based on poly(ethylene-co-tetrafluoroethylene) (ETFE) and poly(etheretherketone) (PEEK) films. The PEMs were irradiated by 500-kGy 
-ray at 300 K, and then characterized in terms of their remaining weight, ion exchange capacity (IEC), proton conductivity, and breaking tensile strength (BTS). The ETFE-based PEM was significantly degraded in all the properties. Contrary to the ETFE PEMs, the PEEK PEM after irradiation did not lose their properties, probably because its aromatic hydrocarbon backbones were very resistant against irradiation. This result makes us expect that the PEEK PEM can be employed in the practical electrolyzer in ITER.
Hirota, Koichi; Hakoda, Teruyuki; Shimada, Akihiko; Taguchi, Mitsumasa; Kimura, Atsushi; Kojima, Takuji
Proceedings of 12th International Conference on Radiation Curing in Asia (RadTech Asia 2011) (Internet), p.108 - 109, 2011/06
We have focused on using MnO
for the oxidation of intermediates produced from electron beam irradiation of VOC. Manganese dioxide can decompose ozone, produced by the irradiation of air containing VOCs, into activated oxygen, which can ultimately oxide the intermediates. Hybrid system equipped with electron accelerator and MnO has demonstrated the complete oxidation of the intermediates produced during the irradiation of xylene and toluene. The electron-beam treatment of dioxin from municipal solid waste incinerator was carried out at Takahama Clean Center in Japan. An incinerator gas of 1000 m
N/h was diverted downstream of a dry electric precipitator and was irradiated with electron beams using an electron accelerator that supplied 300 kV with a maximum energy of 12 kW. The results showed electron-beam is a promising technology for destroying dioxin in exhaust gases.
Hirota, Koichi; Parajuli, D.; Seko, Noriaki
Proceedings of 12th International Conference on Radiation Curing in Asia (RadTech Asia 2011) (Internet), p.136 - 137, 2011/06
Conventional methods for the recovery of precious metals are solvent extraction, chemical precipitation, and use of ion exchange resins. However these methods are facing to significant disadvantages like high capital costs, large chemical and energy requirements, and generation of toxic sludge or other waste products creating additional burden. Development of biomass based sorbents is a better, probably the best, option with lower capital cost and higher efficiency. Although the biomass-sorbents are better than the existing methods, the methods of preparing sorbents from them usually use several kinds of chemicals. In the present work, biomass has been modified with functional groups after electron beam irradiation and its performance for the recovery of precious metals has been studied. The obtained results are compared with that of chemically modified derivative.
Seko, Noriaki; Ueki, Yuji; Thi Yen Ninh, N.*; Bang, L. T.*; Tamada, Masao
Proceedings of 12th International Conference on Radiation Curing in Asia (RadTech Asia 2011) (Internet), p.140 - 141, 2011/06
Ma, H.; Hoshina, Hiroyuki; Seko, Noriaki
Proceedings of 12th International Conference on Radiation Curing in Asia (RadTech Asia 2011) (Internet), p.132 - 135, 2011/06
Hasegawa, Shin; Chen, J.; Koshikawa, Hiroshi; Iwase, Hiroki*; Koizumi, Satoshi; Onuma, Masato*; Maekawa, Yasunari; Iwase, Hiroki*
Proceedings of 12th International Conference on Radiation Curing in Asia (RadTech Asia 2011) (Internet), p.238 - 239, 2011/06
Radiation-induced graft polymerization of sulfo-containing styrene derivatives into crystalline poly(ether ether ketone) (PEEK) substrates was carried out to prepare thermally and mechanically stable polymer electrolyte membranes based on an aromatic hydrocarbon polymer, so-called "super-engineering plastics". Graft polymerization of the sulfo-containing styrene, ethyl 4-styrenesulfonate (E4S) into PEEK substrates with degrees of crystallinity (DC) of 11 - 26% gradually progressed, achieving a grafting degree of more than 50% after 72 hours, whereas graft polymerization of the substrates with DC above 26% did not proceed. When morphological change in these films were measured by SAXS, PEEK films with DC larger than 26% showed a new peak at d=14 nm, corresponding to lamella structure. Thus, the suppression of graft polymerization of PEEK films with DC above 26% was due to obstruct of monomer diffusion by the formation of the oriented lamella structure.
Shimada, Akihiko; Kudo, Hisaaki*; Idesaki, Akira; Sugimoto, Masaki; Yoshikawa, Masahito; Tamura, Kiyotoshi; Seguchi, Tadao*
Proceedings of 12th International Conference on Radiation Curing in Asia (RadTech Asia 2011) (Internet), p.244 - 247, 2011/06
Maekawa, Yasunari; Hasegawa, Shin; Koshikawa, Hiroshi; Chen, J.
Proceedings of 12th International Conference on Radiation Curing in Asia (RadTech Asia 2011) (Internet), p.104 - 105, 2011/06
We applied the radiation-induced grafting to poly(ether ether ketone) film, which was mechanically and thermally stable aromatic hydrocarbon polymers, so-called "super engineering plastics". The developed PEEK-based polymer electrolyte membrane (PEM) with 96 
m thickness exhibited 1.5 times higher conductivity and 2.3 times higher mechanical strength, compared with conventional fluorinated PEM. The single fuel cell device maintained stable operation over 1000 hours under the operation at 95
C. According to the high mechanical strength of PEEK substrates, we could reduce the film thickness of PEEK-based PEM down to 10 m. The PEEK-based PEM with film thickness of 10 and 19 m showed higher cell voltages than that of Nafion at the current density in the range from 0.2 to 1.0 A/cm
.
Ueki, Yuji; Seko, Noriaki; Tamada, Masao
Proceedings of 12th International Conference on Radiation Curing in Asia (RadTech Asia 2011) (Internet), p.144 - 145, 2011/06
-ray pre-irradiation graftingKoshikawa, Hiroshi; Yamaki, Tetsuya; Asano, Masaharu; Maekawa, Yasunari; Yamaguchi, Susumu*; Yamamoto, Kazuya*; Asazawa, Koichiro*; Yamada, Koji*; Tanaka, Hirohisa*
Proceedings of 12th International Conference on Radiation Curing in Asia (RadTech Asia 2011) (Internet), p.240 - 241, 2011/06
The anion-exchange membranes (AEM) for fuel cells were prepared by the radiation-induced graft polymerization of chloromethylstyrene into poly(ethylene-co-tetrafluoroethylene) (ETFE) films and subsequent quaternization of the grafts with trimethylamine. When the AEM were treated in 1M-KOH and washed with N
-saturated water, the membranes with chloride form can be converted quantitatively to hydroxide form. However, the hydroxide form was easily converted to the bicarbonate form by the treatment in non-bubbled (CO dissolved) water. When we introduced the crosslinkers in polymer grafts, which is proved to be very effective in the proton conducting PEM having a poly(styrenesulfonic acid) grafts, the grafted AEM with both chloride and hydroxide forms showed only slight decrease of water uptake. It should be noted that AEM with hydroxide form showed very high tendency to absorb water.