Kinetics of Pu(IV) and Am(III) sorption from natural groundwater to three types of clays were studied at trace concentrations of the elements. Higher K(d) values were determined for sorption of Pu than of Am, and no clear dependence of the K(d) values and the kinetic coefficients on the composition of the clays can be deduced. Kinetic data evaluated by models for six different control processes indicated a sorption mechanism controlled by Pu or Am diffusion in the inert layer on the surface of the clays. Apart from the kinetics of the elements sorption, time-dependent changes in their bonding nature were also studied using a sequential extraction. It was found that Pu(IV) was predominantly associated with amorphous and crystalline Fe oxides as well as natural organic matter sites on the clays, whereas in the case of Am(III) the exchangeable and carbonate sites played the principal role.
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http://dx.doi.org/10.1016/j.jenvrad.2011.07.012 | DOI Listing |
Chemosphere
January 2025
Departamento de Química, Universidade Federal do Paraná, 81531-980, Curitiba-PR, Brasil.
Soil is regarded as a natural repository for strongly adsorbed pollutants since glyphosate (GLY) is preferentially adsorbed by the inorganic fraction of the soil, which may greatly limits its leaching. In this way, understanding how clay mineralogy influences the sorption and transport processes of glyphosate in soils with different mineralogical characteristics is highly relevant. In this work, two clay mineralogy contrasting soils were used to evaluate GLY retention: a Oxisol (OX) with high levels of iron oxides (amorphous and crystalline) and a Inceptisol (IN) with a predominance of kaolinite.
View Article and Find Full Text PDFEnviron Health Insights
January 2025
Department of Environment and Climate Change, Ethiopian Civil Service University, Addis Ababa, Ethiopia.
Background: The decline in wheat output in Ethiopia is widely attributed to pests, which has led to a rise in the usage of pesticides to boost productivity. The degree of pesticides sorption and degradation which influence the likelihood of environmental contamination from pesticides seeping into water bodies from soil has not yet been published for Ethiopian soils. The study aimed at to quantify the levels of pesticide residues, assess glyphosate's adsorption capabilities and degradation rate in the soils.
View Article and Find Full Text PDFWater Res
December 2024
Department of Global Smart City, Sungkyunkwan University (SKKU), 2066, Seobu-ro, Jangan-gu, Suwon, Gyeonggi-do, 16419, Republic of Korea. Electronic address:
J Am Chem Soc
January 2025
Key Laboratory of Polyoxometalate and Reticular Material Chemistry of the Ministry of Education, Faculty of Chemistry, Northeast Normal University, Changchun 130024, P. R. China.
Uranium (U), a high-performing, low-emission energy source, is driving sustainable economic growth. Herein, we synthesized two crystalline phases (HPOC-α and β) by an unreported amidoxime organic cage used for uranium capture. The revealed crystal structures and uranium adsorption test showed that accessible functional groups were essential to uranyl ions sorption.
View Article and Find Full Text PDFBiomacromolecules
January 2025
Department of Biosystems and Soft Matter, Institute of Fundamental Technological Research, Polish Academy of Sciences, Pawińskiego 5B, 02-106 Warsaw, Poland.
Cross-linking bonds adjacent polymer chains into a three-dimensional network. Cross-linked poly(vinyl alcohol) (PVA) turns into a hydrogel, insoluble structure exhibiting outstanding sorption properties. As an electrospinnable polymer, PVA enables the creation of nanofibrous hydrogels resembling biological tissues, thus ideal for nature-inspired platforms.
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