Chemical and structural characterization of copper adsorbed on mosses (Bryophyta) A. G. González, F. Jiménez-Villacorta, A. K. Beike [et.al.]
Material type: ArticleSubject(s): химические характеристики | структурные характеристики | медь | адсорбция меди | мхиGenre/Form: статьи в журналах Online resources: Click here to access online In: Journal of hazardous materials Vol. 308. P. 343-354Abstract: The adsorption of copper on passive biomonitors (devitalized mosses Hypnum sp., Sphagnum denticulatum, Pseudoscleropodium purum and Brachythecium rutabulum) was studied under different experimental conditions such as a function of pH and Cu concentration in solution. Cu assimilation by living Physcomitrella patents was also investigated. Molecular structure of surface adsorbed and incorporated Cu was studied by X-ray Absorption Spectroscopy (XAS). Devitalized mosses exhibited the universal adsorption pattern of Cu as a function of pH, with a total binding sites number 0.05–0.06 mmolgdry−1 and a maximal adsorption capacity of 0.93–1.25 mmolgdry−1 for these devitalized species. The Extended X-ray Absorption Fine Structure (EXAFS) fit of the first neighbor demonstrated that for all studied mosses there are ∼4.5 O/N atoms around Cu at ∼1.95 Å likely in a pseudo-square geometry. The X-ray Absorption Near Edge Structure (XANES) analysis demonstrated that Cu(II)-cellulose (representing carboxylate groups) and Cu(II)-phosphate are the main moss surface binding moieties, and the percentage of these sites varies as a function of solution pH. P. patens exposed during one month to Cu2+ yielded ∼20% of Cu(I) in the form of Cu–S(CN) complexes, suggesting metabolically-controlled reduction of adsorbed and assimilated Cu2+.Библиогр.: 60 назв.
The adsorption of copper on passive biomonitors (devitalized mosses Hypnum sp., Sphagnum denticulatum, Pseudoscleropodium purum and Brachythecium rutabulum) was studied under different experimental conditions such as a function of pH and Cu concentration in solution. Cu assimilation by living Physcomitrella patents was also investigated. Molecular structure of surface adsorbed and incorporated Cu was studied by X-ray Absorption Spectroscopy (XAS). Devitalized mosses exhibited the universal adsorption pattern of Cu as a function of pH, with a total binding sites number 0.05–0.06 mmolgdry−1 and a maximal adsorption capacity of 0.93–1.25 mmolgdry−1 for these devitalized species. The Extended X-ray Absorption Fine Structure (EXAFS) fit of the first neighbor demonstrated that for all studied mosses there are ∼4.5 O/N atoms around Cu at ∼1.95 Å likely in a pseudo-square geometry. The X-ray Absorption Near Edge Structure (XANES) analysis demonstrated that Cu(II)-cellulose (representing carboxylate groups) and Cu(II)-phosphate are the main moss surface binding moieties, and the percentage of these sites varies as a function of solution pH. P. patens exposed during one month to Cu2+ yielded ∼20% of Cu(I) in the form of Cu–S(CN) complexes, suggesting metabolically-controlled reduction of adsorbed and assimilated Cu2+.
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