Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Kozai, Naofumi; Onuki, Toshihiko; Komarneni, S.*
Journal of Materials Chemistry, 17(12), p.2993 - 2996, 2002/12
Here we report the extremely high and selective uptake of selenium oxyanions by a novel exchanger, NiZn
(OH)
(OCOCH
)
・nH
O that has brucite-type hydroxide layers with OCOCH
anions in the interlayers. This Ni-Zn basic salt exhibited very high selectivity for Se(IV) (Kd = 9.0x10
ml/g with an initial Se(IV) concentration of 1x10
M) in the presence of 0.1M Cl
solution while the well known anionic clay, Mg
Al(OH)
NO
・nH
O showed a Kd of 6.0x10
ml/g under the same conditions. The uptake of Se(IV) on the Ni-Zn basic salt was found to be irreversible when treated with solutions containing 1N Cl
, 1N NO
, or 1N PO
, while the Se(IV) sorbed on anionic clay was easily desorbed in a 1M Cl
solution. This novel exchanger also showed high Kd (2.6
10
ml/g at an initial Se concentration of 1
10
M) for Se(VI) and therefore it is expected to be useful for decontamination and removal of selenium oxyanions from contaminated water.
; ; ; ; ;
JAERI-M 85-039, 26 Pages, 1985/03
no abstracts in English
Kumagai, Yuta; Kimura, Atsushi; Taguchi, Mitsumasa
no journal, ,
Zeolite minerals are suitable adsorbents for removal of radioactive cesium in water, because of their high radiation resistances. However, irradiation of zeolites results in decomposition of water adsorbed on the zeolites. Water decomposition produces hydrogen (H) and hydrogen peroxide (H
O
). H
production has a risk of making an explosive gas mixture. H
O
causes corrosion of metals and alloys. Therefore, the radiation effects are required to be assessed and controlled. In this study, H
and H
O
production by irradiation of zeolites in aqueous solution are comparatively studied among different types of zeolites, A-, X-, Y- and mordenite-types. The mixtures of the zeolites and aqueous solution were irradiated by
Co
-rays. The A-type and the X-type zeolites produced more H
than the Y-type and the mordenite-type. In contrast, the H
O
production was inhibited by the addition of zeolites. The A-type and the X-type zeolites showed remarkable inhibition. The A-type and the X-type contains more aluminum in their frameworks than the others do. Therefore, the results suggest that aluminum sites have an important role in the reactions induced by irradiation.