タグ「Sorption」
Title: Pu and Am sorption to the Baltic Sea bottom sediments
Author: G. Lujanienė, P. Beneš, K. Štamberg, K. Jokšas, I. Kulakauskaitė
Reference: Journal of Radioanalytical and Nuclear Chemistry , March 2013, Volume 295, Issue 3, pp 1957-1967
DOI: 10.1007/s10967-012-2281-1
Keywords: Pu(IV), Pu(V), Bottom sediments, Seawater, Sorption
Abstract: Sorption of Am and Pu isotopes to bottom sediments of the Baltic Sea has been studied under natural and laboratory conditions. Data obtained from sequential extraction, sorption of Am(III), Pu(IV) and Pu(V) as well as oxidation state distribution experiments have shown that Pu(V) sorption mechanism includes a very fast Pu(V) reduction (reaction rate ≤ 2.33 × 10−3 s−1) to Pu(IV) by humic substances and/or by Fe(II) to Pu(IV) and partly to Pu(III). Following reduction Pu isotopes were bound to various components of bottom sediments via ion exchange and surface complexation reactions and a slow incorporation into the crystalline structure of Fe minerals. Kinetics experiments showed that the sorption of Pu(V), Pu(IV) and Am(III) to bottom sediments from natural seawater was controlled by the inert layer diffusion process.
ＵＲＬ：http://link.springer.com/article/10.1007/s10967-012-2281-1
Author: S.Yu. Bratskaya, V.A. Avramenko, V.I. Sergienko, Yu.P. Korchagin, A.M. Egorin
Reference: Patent, Vladivostok, 27.12.2009, patent holder: Institution of the Russian Academy of Sciences, Institute of Chemistry, Far Eastern Branch of Russian Academy of Sciences
Keywords: colloidally-stable nanosorbent, decontamination, soil
Abstract: The invention relates to environmental protection, namely, to the decontamination of soil, ground, sand, ion-exchange resins, slag and other solid granular wastes. It can be applied in nuclear power plants, radio-chemical industries, and territories affected by anthropogenic catastrophe and accidental spills of liquid radioactive waste. The colloid-resistant nano sorbent for decontamination of solid granular materials comprises reaction product, combined with an equivalent amount of cations from the group of transition metals and hexacyanoferrate anion, which are precursors of sorbent formed among stable carboxyl polymer colloid.
URL: http://www.findpatent.ru/patent/240/2401469.html
Author: E.V. Nogovytsina
Reference: Dissertation, 2002 (published in Ekaterinburg, 2011)
Keywords: radiation liquid waste, decontamination, cesium, sorption
URL: http://library.gpntb.ru/cgi-bin/irbis64r_simplesite/cgiirbis_64.exe
Author: Gerasimova L. G., Maslova M. V., Nikolaev A. I.
Reference: Gazette “ЦВЕТНЫЕ МЕТАЛЛЫ“, 2011
ISSN: 0372-2929
DOI:
Keywords: Sorption, desorption, composite sorbents, flow sheet, wastewater, non-ferrous metal cations, radioactive isotopes
Abstract: A method for the production of a new, composite inorganic adsorbent based on titanium phosphate derived from current wastes of apatite-nepheline ore processing is described. The new variant of waste recovery makes it possible to implement advanced and environmentally friendly patterns. In this work, a scientific justification for parameters of titanium phosphate precursor synthesis and treatment is proposed. The technology is highly effective; the adsorbent can be used in cleaning of weak-salt aqueous effluents. The chemical stability of the composite adsorbent in various solutions has been studied to determine the optimal operating conditions for it. It has been found that after five sorption desorption cycles the material’s ion-exchanges capacity remains practically unchanged. The possibility of recovering the sorbent saturated with transition metals has been examined by using different mineral acids. Methods for the spent material utilization in the production of building fillers are discussed. The paper provides the data on purification of real wastewater of multimineral ore processing. It was noted that the cations of water hardness are first absorbed by the material, later becoming displaced by elements forming stronger bonds with phosphate groups. By the example of artificial radioactive solutions containing 137Cs, 152Eu, 234Th, 238U, 60Со, we determined the material’s ion-exchange capacity and its dependence on the adsorbent’s initial bulk density and number of sorption stages. The material has demonstrated superior ion-exchange properties in wastewater purification from non-ferrous metals and radionuclides.
URL: http://www.rudmet.ru/journal/656/article/8383/
Title: 90Sr migration to the geo-sphere from a waste burial in the Chernobyl exclusion zone
Author: L Dewiere, D Bugai, C Grenier, V Kashparov, N Ahamdach
Reference: Journal of Environmental Radioactivity, Volume 74, Issues 1–3, 2004, Pages 139-150
DOI: http://dx.doi.org/10.1016/j.jenvrad.2004.01.019
Keywords: Chernobyl; Strontium-90; Fuel particles; Groundwater; Retardation; Sorption; Hydro-dispersion
Abstract: Results are presented from an ongoing field-scale experimental study (namely the Chernobyl Pilot Site project) aimed at characterization of processes controlling 90Sr releases from a shallow trench containing nuclear fuel particles, and subsequent radionuclide transport in the underlying sandy aquifer at the Chernobyl nuclear power plant site. Microscopic analyses of waste material and leaching experiments have shown that 10–30% of the radioactive inventory is associated with chemically extra-stable Zr–U–O particles. The largest fraction of 90Sr activity in the trench (≈30–60%) is currently associated with relatively slowly dissolving non-oxidized UO2 matrix fuel particles. The 90Sr migration velocity in the eolian sand aquifer is retarded by sorption to ≈9% of groundwater flow velocity (Kd ≈ 2 ml/g). The dispersivity values for non-reactive solute transport in the aquifer predicted by geostatistics (i.e. 0.8 6 cm) were confirmed by a natural gradient tracer test using 36Cl. The observed negative correlation between hydraulic conductivity and Kd of aquifer sediments suggests that 90Sr could be subjected to larger dispersion in the subsurface compared with 36Cl.
URL: http://www.sciencedirect.com/science/article/pii/S0265931X04000244
