Sorption of lanthanides on smectite and kaolinite

Coppin, Frédéric; Berger, G.; Bauer, Andreas; Castet, Sylvie; Loubet, M.

doi:10.1016/s0009-2541(01)00283-2

Cited by 417 publications

(256 citation statements)

References 41 publications

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“…The structure of these Ln-bentonites is studied by XRD, XRF, SEM-EDX, complexometric titration, ICP-OES and Mössbauer-spectroscopy. The results can prove the suggestion by Coppin et al [16], Wu et al [19], and Tertre et al [17] on the intercalation of Ln ions in the interlayer of smectite. In addition, information will be shown on the structural parameters of trivalent lanthanide cation exchanged bentonites.…”

Section: Introductionsupporting

confidence: 89%

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Preparation and structure’s analyses of lanthanide (Ln) -exchanged bentonites

Kovács

Baradács

Kónya

et al. 2017

Colloids and Surfaces A: Physicochemical and Engineering Aspect

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Please cite this article as: Eszter Mária Kovács, Eszter Erdélyiné Baradács, Péter Kónya, Péter Kovács-Pálffy, Sándor Harangi, József Kónya, Noémi M.Nagy, Preparation and structure's analyses of lanthanide (Ln) -exchanged bentonites, Colloids and Surfaces A: Physicochemical and Engineering Aspects http://dx.doi.org/10. 1016/j.colsurfa.2017.02.085 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. HIGHLIGHTS REE-exchanged bentonites were prepared from Ca-bentonite by ion exchange.  The La 3+ -, Ce 3+ -, and Gd 3+ -bentonite, the sorbed ion amount was higher than the CEC.  In case of lanthanum-bentonite, the rare earth quantity is as high as 136% of CEC.  The iron(III) content of lanthanum bentonite is less than that of the original Cabentonite. 4Abstract The interaction between Lanthanides (Ln)-ions and Ca-bentonite and the structural changes accompanying were studied. Ln-exchanged bentonites were prepared from Cabentonite (Istenmezeje, Hungary) by ion exchange in three consecutive washings with lanthanide solutions. Scanning Eletronmicroscopy Energy Dispersive X-ray spectroscopy (SEM-EDX) studies showed even distribution of Lns and other components of bentonite. The natural bentonite and the lanthnide exchanged bentonites were characterized by X-ray diffraction (XRD), which revealed the same mineral composition, and the increase of the basal spacing of montmorillonite from 1.465 (Ca 2+ ) to 1.577 nm (REE 3+ ). The d001 basal spacing of lanthanide montmorillonite increases as the ion radius of the lanthanide cation increases. The Fe 3+ , and Lns 3+ amount on the bentonite were determined by X-rayfluorescence spectrometry (XRF) elemental analysis. The amount of exchanged Lns were determined by washing the Ln-bentonite with 1M ammonium-acetate, and measuring the amount of Ln released, using inductively coupled plasma optical emission spectrometry (ICP-OES). In most Ln-bentonites, the quantity of the exchanged Ln ions was about 80-90% of the cation exchange capacity (CEC) of the bentonite. In case of some lanthanides bentonite (La 3+ , Ce 3+ , and Gd 3+ ), however, the sorbed quantity of lanthanum ions was higher than the cation exchange capacity. In case of lanthanum-bentonite, the lanthanide quantity is as high as 136% of CEC. Moreover, the iron(III) content of lanthanum bentonite is less than that of the original Ca-bentonite. Mössbauer spectra of the La-, Ce-, and Gd-exchanged samples at 78 K revealed an unexpected magnetically split component that was absent from the Ca-bentonite. This component may belong to interlayer Fe. This iron can be released from the octahedral positions crystal lattice.5

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Section: Introductionsupporting

confidence: 89%

“…Coppin et al [16] studied the complete lanthanide series sorption on kaolinite and Na-montmorillonite. They mentioned that the Ln sorption is controlled by the nature of the clay minerals, the pH and the ionic strength.…”

Section: Introductionmentioning

confidence: 99%

Preparation and structure’s analyses of lanthanide (Ln) -exchanged bentonites

Kovács

Baradács

Kónya

et al. 2017

Colloids and Surfaces A: Physicochemical and Engineering Aspect

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“…It is reported that this mineral can even withstand acidic attack up to a pH around 1 [8]. As was discussed earlier, the sorption sites of kaolinite are located mainly on the surface and edge parts [3]; thus the basal (interlayer) space is expected to retain its dimensions upon sorption. Nevertheless, it is reported that incorporation of foreign ions within the kaolinite structure would bring about a stress on the kaolinite molecule, the thing that might influence properties such as swelling capacity, compaction capability, and the double-layer behavior of the clay [25].…”

Section: Xrpd Analysis Of the Cs-loaded Mineralsmentioning

confidence: 78%

“…The sorption properties of this clay are solely determined by the nature of its surface and edges. Kaolinite possesses a variable charge that can be related to the reactions between ionizable surface groups located at the edges or at the gibbsite basal plane and the ions present in aqueous solution [3]. The same study showed that the silanol groups (Si-OH) at the crystal edges of kaolinite contribute exclusively to the negative charge, through formation of SiO − surface complexes at moderate and high pH values.…”

Section: Introductionmentioning

confidence: 94%

Physicochemical characterization of the retardation of aqueous Cs+ ions by natural kaolinite and clinoptilolite minerals

Shahwan

Akar

Eroğlu

2005

Journal of Colloid and Interface Science

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The aim of this study was to carry out kinetic, thermodynamic, and surface characterization of the sorption of Cs + ions on natural minerals of kaolinite and clinoptilolite. The results showed that sorption followed pseudo-second-order kinetics. The activation energies were 9.5 and 13.9 kJ/mol for Cs + sorption on kaolinite and clinoptilolite, respectively. Experiments performed at four different initial concentrations of the ion revealed that the percentage sorption of Cs + on clinoptilolite ranged from 90 to 95, compared to 28 to 40 for the kaolinite case. At the end of a 1 week period, the percentage of Cs + desorption from clinoptilolite did not exceed 7%, while it amounted to more than 30% in kaolinite, indicating more stable fixation by clinoptilolite. The sorption data were best described using Freundlich and D-R isotherm models. Sorption showed spontaneous and exothermic behavior on both minerals, with H 0 being −6.3 and −11.4 kJ/mol for Cs + uptake by kaolinite and clinoptilolite, respectively. Expanding the kaolinite interlayer space from 0.71 to 1.12 nm using DMSO intercalation, did not yield a significant enhancement in the sorption capacity of kaolinite, indicating that the surface and edge sites of the clay are more energetically favored. EDS mapping and elemental analysis of the surface of kaolinite and clinoptilolite revealed more intense signals on the surface of the latter with an even distribution of sorbed Cs + onto the surfaces of both minerals.

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“…The behaviour of the dissolved YREEs in the presence of montmorillonite was investigated by Takahashi et al (2004), and Coppin et al (2002), although the latter authors excluded Yttrium from their investigation.…”

Section: Introductionmentioning

confidence: 99%

Alteration effects of volcanic ash in seawater: Anomalous Y/Ho ratios in coastal waters of the Central Mediterranean sea

Censi

Sprovieri

Larocca

et al. 2007

Geochimica et Cosmochimica Acta

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This paper presents the results of a study based on data collected during the oceanographic cruise ANSIC 2001 carried out in the Ionian Sea during the explosive activity of Mount Etna in the summer of 2001. Anomalous low values of Y/Ho ratios in seawater suggest extensive scavenging processes on the surfaces of smectitic alteration products, with Y and Ho fractionation controlled by the differences in their electronic configurations and behaviour during solution/surface complexation equilibria. These processes can also be traced through the presence of significant tetrad effects recorded in the chondrite-normalised Rare Earth Elements and Yttrium (YREEs) patterns of suspended particulate matter. This suggests that the preferential Y scavenging from seawater is due to the formation of inner-sphere complexes with OH À groups on montmorillonite crystal surfaces. The preliminary results of kinetic experiments of YREE released from volcanic ash to coexisting seawater, and the related effects on Y/Ho ratios and Ce anomalies, are consistent with the fractionation of Light Rare Earth Elements (LREEs) with respect to Heavy Rare Earth Elements (HREEs) observed in dissolved phase. They suggest a behaviour of Y similar to that reported for LREEs, particularly for Ce and Pr.

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Sorption of lanthanides on smectite and kaolinite

Cited by 417 publications

References 41 publications

Preparation and structure’s analyses of lanthanide (Ln) -exchanged bentonites

Preparation and structure’s analyses of lanthanide (Ln) -exchanged bentonites

Physicochemical characterization of the retardation of aqueous Cs+ ions by natural kaolinite and clinoptilolite minerals

Alteration effects of volcanic ash in seawater: Anomalous Y/Ho ratios in coastal waters of the Central Mediterranean sea

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