Mechanism of Selenite Removal by a Mixed Adsorbent Based on Fe–Mn Hydrous Oxides Studied Using X-ray Absorption Spectroscopy

Handle URI:
http://hdl.handle.net/10754/598791
Title:
Mechanism of Selenite Removal by a Mixed Adsorbent Based on Fe–Mn Hydrous Oxides Studied Using X-ray Absorption Spectroscopy
Authors:
Chubar, Natalia; Gerda, Vasyl; Szlachta, Małgorzata
Abstract:
© 2014 American Chemical Society. Selenium cycling in the environment is greatly controlled by various minerals, including Mn and Fe hydrous oxides. At the same time, such hydrous oxides are the main inorganic ion exchangers suitable (on the basis of their chemical nature) to sorb (toxic) anions, separating them from water solutions. The mechanism of selenite adsorption by the new mixed adsorbent composed of a few (amorphous and crystalline) phases [maghemite, MnCO3, and X-ray amorphous Fe(III) and Mn(III) hydrous oxides] was studied by extended X-ray absorption fine structure (EXAFS) spectroscopy [supported by Fourier transform infrared (FTIR) and X-ray diffraction (XRD) data]. The complexity of the porous adsorbent, especially the presence of the amorphous phases of Fe(III) and Mn(III) hydrous oxides, is the main reason for its high selenite removal performance demonstrated by batch and column adsorption studies shown in the previous work. Selenite was bound to the material via inner-sphere complexation (via oxygen) to the adsorption sites of the amorphous Fe(III) and Mn(III) oxides. This anion was attracted via bidentate binuclear corner-sharing coordination between SeO3 2- trigonal pyramids and both FeO6 and MnO6 octahedra; however, the adsorption sites of Fe(III) hydrous oxides played a leading role in selenite removal. The contribution of the adsorption sites of Mn(III) oxide increased as the pH decreased from 8 to 6. Because most minerals have a complex structure (they are seldom based on individual substances) of various crystallinity, this work is equally relevant to environmental science and environmental technology because it shows how various solid phases control cycling of chemical elements in the environment.
Citation:
Chubar N, Gerda V, Szlachta M (2014) Mechanism of Selenite Removal by a Mixed Adsorbent Based on Fe–Mn Hydrous Oxides Studied Using X-ray Absorption Spectroscopy. Environ Sci Technol 48: 13376–13383. Available: http://dx.doi.org/10.1021/es503606j.
Publisher:
American Chemical Society (ACS)
Journal:
Environmental Science & Technology
KAUST Grant Number:
KUK-C1-017-12
Issue Date:
18-Nov-2014
DOI:
10.1021/es503606j
PubMed ID:
25325790
Type:
Article
ISSN:
0013-936X; 1520-5851
Sponsors:
King Abdullah University of Science and Technology (KAUST) (Award KUK-C1-017-12) and Dutch Ministry for Scientific Research (NWO), which funded the EXAFS studies conducted in spring 2011, are gratefully acknowledged for the financial support of this work. The authors also thank the anonymous reviewers and the editor who helped to improve this work considerably.
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Full metadata record

DC FieldValue Language
dc.contributor.authorChubar, Nataliaen
dc.contributor.authorGerda, Vasylen
dc.contributor.authorSzlachta, Małgorzataen
dc.date.accessioned2016-02-25T13:41:18Zen
dc.date.available2016-02-25T13:41:18Zen
dc.date.issued2014-11-18en
dc.identifier.citationChubar N, Gerda V, Szlachta M (2014) Mechanism of Selenite Removal by a Mixed Adsorbent Based on Fe–Mn Hydrous Oxides Studied Using X-ray Absorption Spectroscopy. Environ Sci Technol 48: 13376–13383. Available: http://dx.doi.org/10.1021/es503606j.en
dc.identifier.issn0013-936Xen
dc.identifier.issn1520-5851en
dc.identifier.pmid25325790en
dc.identifier.doi10.1021/es503606jen
dc.identifier.urihttp://hdl.handle.net/10754/598791en
dc.description.abstract© 2014 American Chemical Society. Selenium cycling in the environment is greatly controlled by various minerals, including Mn and Fe hydrous oxides. At the same time, such hydrous oxides are the main inorganic ion exchangers suitable (on the basis of their chemical nature) to sorb (toxic) anions, separating them from water solutions. The mechanism of selenite adsorption by the new mixed adsorbent composed of a few (amorphous and crystalline) phases [maghemite, MnCO3, and X-ray amorphous Fe(III) and Mn(III) hydrous oxides] was studied by extended X-ray absorption fine structure (EXAFS) spectroscopy [supported by Fourier transform infrared (FTIR) and X-ray diffraction (XRD) data]. The complexity of the porous adsorbent, especially the presence of the amorphous phases of Fe(III) and Mn(III) hydrous oxides, is the main reason for its high selenite removal performance demonstrated by batch and column adsorption studies shown in the previous work. Selenite was bound to the material via inner-sphere complexation (via oxygen) to the adsorption sites of the amorphous Fe(III) and Mn(III) oxides. This anion was attracted via bidentate binuclear corner-sharing coordination between SeO3 2- trigonal pyramids and both FeO6 and MnO6 octahedra; however, the adsorption sites of Fe(III) hydrous oxides played a leading role in selenite removal. The contribution of the adsorption sites of Mn(III) oxide increased as the pH decreased from 8 to 6. Because most minerals have a complex structure (they are seldom based on individual substances) of various crystallinity, this work is equally relevant to environmental science and environmental technology because it shows how various solid phases control cycling of chemical elements in the environment.en
dc.description.sponsorshipKing Abdullah University of Science and Technology (KAUST) (Award KUK-C1-017-12) and Dutch Ministry for Scientific Research (NWO), which funded the EXAFS studies conducted in spring 2011, are gratefully acknowledged for the financial support of this work. The authors also thank the anonymous reviewers and the editor who helped to improve this work considerably.en
dc.publisherAmerican Chemical Society (ACS)en
dc.titleMechanism of Selenite Removal by a Mixed Adsorbent Based on Fe–Mn Hydrous Oxides Studied Using X-ray Absorption Spectroscopyen
dc.typeArticleen
dc.identifier.journalEnvironmental Science & Technologyen
dc.contributor.institutionGlasgow Caledonian University, Glasgow, United Kingdomen
dc.contributor.institutionUtrecht University, Utrecht, Netherlandsen
dc.contributor.institutionTaras Shevchenko National University of Kyiv, Kiev, Ukraineen
dc.contributor.institutionPolitechnika Wroclawska, Wroclaw, Polanden
kaust.grant.numberKUK-C1-017-12en
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