Competitive sorption of protons and metal cations onto kaolinite: experiments and modeling

Heidmann, Ilona; Christl, Iso; Leu, Christian; Kretzschmar, Ruben

doi:10.1016/j.jcis.2004.08.019

Cited by 98 publications

(110 citation statements)

References 37 publications

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“…5,7,14,16,17 The strong adsorption by goethite at pH > 4.0 is consistent with many observations in the literature, where iron (oxy)hydroxides such as amorphous iron hydroxide, ferrihydrite and goethite in aquifer sediments have been identified as major sinks for U(VI). 6,13,15,18−20 Compared to the fine fractions (Figure 2c,d), kaolinite exhibits stronger U(VI) adsorption at pH < 4.0 and a similar adsorption extent at pH > 4.0 (up to 7.0), and goethite shows a similar adsorption extent at pH < 4.0 and stronger adsorption at pH > 4.0 (up to 8.0).…”

Section: +supporting

confidence: 79%

“…Our modeling approach is summarized by the following points: (i) U(VI) is adsorbed via formation of bidentate surface complexes; (ii) in addition to the UO 2 2+ surface species ternary uranyl-carbonato surface complexes are formed. In agreement with our goethite system, we assumed that similar surface complexes ( Table 2, i.e., (>SOH) 2 UO 2 + , (>SOH) 2 UO 2 CO 3 − ) are formed on the kaolinite amphoteric edge sites; (iii) for kaolinite, cation exchange sites (>X − ) and amphoteric edge sites (>SOH) with a 1-pK model were chosen based on the data of Heidmann et al 14,35 The >SOH sites simply represent both silanol (>SiOH) and aluminol (>AlOH) sites on kaolinite surfaces. The treatment of amphoteric edge sites as a single surface site is generally recognized as a convenient modeling framework rather than a precise representation of actual functional groups existing at clay edge sites.…”

Section: +mentioning

confidence: 97%

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Uranium(VI) Adsorption and Surface Complexation Modeling onto Background Sediments from the F-Area Savannah River Site

Dong

Tokunaga

Davis

et al. 2012

Environ. Sci. Technol.

119

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TitleUranium(VI) adsorption and surface complexation modeling onto background sediments from the F-Area Savannah River site ABSTRACT: The mobility of an acidic uranium waste plume in the F-Area of Savannah River Site is of great concern. In order to understand and predict uranium mobility, U(VI) adsorption experiments were performed as a function of pH using background F-Area aquifer sediments and reference goethite and kaolinite (major reactive phases of F-Area sediments), and a component-additivity (CA) based surface complexation model (SCM) was developed. Our experimental results indicate that the fine fractions (≤45 μm) in sediments control U(VI) adsorption due to their large surface area, although the quartz sands show a stronger adsorption ability per unit surface area than the fine fractions at pH < 5.0. Kaolinite is a more important sorbent for U(VI) at pH < 4.0, while goethite plays a major role at pH > 4.0. Our CA model combines an existing U(VI) SCM for goethite and a modified U(VI) SCM for kaolinite along with estimated relative surface area abundances of these component minerals. The modeling approach successfully predicts U(VI) adsorption behavior by the background F-Area sediments. The model suggests that exchange sites on kaolinite dominate U(VI) adsorption at pH < 4.0, goethite and kaolinite edge sites cocontribute to U(VI) adsorption at pH 4.0−6.0, and goethite dominates U(VI) adsorption at pH > 6.0.

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Section: +supporting

confidence: 79%

Section: +mentioning

confidence: 97%

Uranium(VI) Adsorption and Surface Complexation Modeling onto Background Sediments from the F-Area Savannah River Site

Dong

Tokunaga

Davis

et al. 2012

Environ. Sci. Technol.

119

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“…The sorption of trace elements on kaolin depends on several physico-chemical parameters (pH, ionic strength, ion competition, and surface modification) (Heidmann et al 2005;Sarkar et al 2000;Srivastava et al 2005). Concerning OTC, it was previously shown that tin compounds are sorbed on suspended clay and sand particles following two processes: (a) by electrostatic interaction and/or (b) by hydrophobic binding (Bueno et al 1998;Weidenhaupt et al 1997).…”

mentioning

confidence: 99%

Tributyltin Solubilization and Degradation from Spiked Kaolin Using Different Reagents

Yvon

Hécho

Donard

2010

Water Air Soil Pollut

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Conditions for tributyltin (TBT) solubilization and degradation were investigated. These conditions were optimized to remove or degrade organotin compounds (OTC) in spiked kaolin. TBT-spiked kaolin and reagents with specific chemical properties were tested in a batch reactor using a solid matrix model. The final concentrations of butyltin compounds in kaolin were determined by gas chromatography coupled with a pulsed flame photometric detector. Best results were obtained under acidic conditions (2

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“…The sorption capacity of kaolin clay is pH dependent because its surface charge is more negative for pH values higher than its point of zero charge PZC [90]. Studies of Heidmann et al [31,32], Alkan et al [2] and Jiang et al [34,35] confirmed that the adsorption of lead, copper, nickel and cadmium on kaolinite increases with increasing pH. Hence, the adsorption decrease noticed here at higher concentrations, which was most distinct for the adsorption of copper on the untreated kaolinite (Fig.…”

Section: Batch Sorption Tests Resultsmentioning

confidence: 99%

Modified clays for barriers: a review

Emidio

Verástegui-Flores

Mazzieri

et al. 2017

Innov. Infrastruct. Solut.

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The aim of this Specialized Lecture is to present the recent advances and issues, as well as original research, on Modified Clays for Barriers. Topics of interest include:(1) long-term hydraulic performance of modified clays for GCLs, (2) chemico-osmotic and diffusion efficiency of modified clays, (3) modeling coupled chemical-hydraulicmechanical behavior of modified clays, (4) wet and dry ageing of modified clays, (5) use of novel bentonites for vertical barrier applications, and (6) organoclays for various barrier applications. In addition, the possible reuse of dredged sediments after polymer treatment will also be discussed. Environmental management and handling of dredged sediments are important worldwide because enormous amounts of dredged material emerge from maintenance, construction and remedial works within water systems. Usually these materials after temporary upland disposal in lagoons are disposed in landfills. The aim of this study is to analyse the possible reuse of these sediments as a low-cost alternative material for landfill covers. The mechanisms through which polymers can improve the efficiency of dredged sediments for waste containment low permeable barriers are discussed.

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Competitive sorption of protons and metal cations onto kaolinite: experiments and modeling

Cited by 98 publications

References 37 publications

Uranium(VI) Adsorption and Surface Complexation Modeling onto Background Sediments from the F-Area Savannah River Site

Uranium(VI) Adsorption and Surface Complexation Modeling onto Background Sediments from the F-Area Savannah River Site

Tributyltin Solubilization and Degradation from Spiked Kaolin Using Different Reagents

Modified clays for barriers: a review

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