Sulfur Speciation in Soil by S <i>K</i>-Edge XANES Spectroscopy: Comparison of Spectral Deconvolution and Linear Combination Fitting

Prietzel, Jörg; Botzaki, Anna; Tyufekchieva, Nora; Brettholle, Mareike; Thieme, Jürgen; Klysubun, Wantana

doi:10.1021/es102180a

Cited by 133 publications

(127 citation statements)

References 24 publications

Supporting

Mentioning

122

Contrasting

Order By: Relevance

“…6B). The pre-edge peaks are usually ascribed to the presence of low oxidation state of S [ [36][37][38]. However, the observed pre-edge peaks in this study were not induced by other lower valence S-compounds, as evidenced by the failure in matching their peak positions with reference compounds (Fig.…”

Section: Nexafs Analysismentioning

confidence: 56%

Mechanistic study of PFOS adsorption on kaolinite and montmorillonite

Zhang

Yan

Jing

2014

Colloids and Surfaces A: Physicochemical and Engineering Aspect

View full text Add to dashboard Cite

h i g h l i g h t s• The mechanisms of PFOS adsorption on clay minerals are examined at molecular level.• XANEFS analysis provides direct evidence for chemical adsorption.• FTIR spectra in situ monitors the interaction process of PFOS with clay minerals.• PFOS could insert into the interlayers of montmorillonite.• The HA coating decreased PFOS adsorption on kaolinite and montmorillonite. Adsorption of perfluorooctane sulfonate (PFOS) on clay minerals is pivotal in the fate and transport of PFOS in the environment. Understanding the PFOS adsorption mechanisms, however, presents challenges, especially in the presence of natural organic substances. In this study, the adsorption mechanism of PFOS on kaolinite and montmorillonite, with and without humic acids (HA), were investigated using batch experiments, ATR-FTIR spectroscopy, zeta potential, NEXAFS, and XRD. The results showed that PFOS had a higher adsorption capacity on kaolinite than on montmorillonite, both with a rapid formation of an outer-sphere complex followed by a slow ligand exchange reaction with the elimination of adsorbed H 2 O molecules. In addition to nonspecific hydrophobic and electrostatic interactions, specific chemisorption also exists between sulfonate group of PFOS and hydroxyl group on surfaces of clay minerals. The HA coating on clay materials inhibited PFOS adsorption due to its occupation of adsorption sites and increased electrostatic repulsion. The insights gained from this study improve our understanding on the mechanism of multilateral forces on PFOS adsorption at the molecular level.

show abstract

Section: Nexafs Analysismentioning

confidence: 56%

Mechanistic study of PFOS adsorption on kaolinite and montmorillonite

Zhang

Yan

Jing

2014

Colloids and Surfaces A: Physicochemical and Engineering Aspect

View full text Add to dashboard Cite

show abstract

“…[46] In contrast, in this study with freshwater lake sediments, thiols form on time scales of days to weeks, most likely as a result of a combination of factors, such as the high rates of sulfate reduction and the nature of the labile OM deposited from the water column. One hypothesis worth further investigation is that soilderived OM in lake sediments may be promoting fast thiol formation because of its high content of oxidised S (up to 98 % total S org [48] ), mainly in the form of easily hydrolysable ester-SO 4 [25,49] or sulfonate. [50] Controls on As mobility XAS results show that As sorbed onto Fe oxyhydroxides is present at the end of the experiment (Table 2), suggesting incomplete sulfidisation of the Fe oxyhydroxides.…”

Section: Discussionmentioning

confidence: 99%

Arsenic binding to organic and inorganic sulfur species during microbial sulfate reduction: a sediment flow-through reactor experiment

et al. 2013

View full text Add to dashboard Cite

Environmental context. The use of water contaminated with arsenic for drinking and irrigation is linked to water and food borne diseases throughout the world. Although reducing conditions in soils and sediments are generally viewed as enhancing arsenic mobility in subsurface environments, we show they can actually promote As sequestration in the presence of reduced sulfur species and labile organic matter. We propose that sulfurisation of organic matter and subsequent binding of As to thiol groups may offer an innovative pathway for As remediation.Abstract. Flow-through reactors (FTRs) were used to assess the mobility of arsenic under sulfate reducing conditions in natural, undisturbed lake sediments. The sediment slices in the FTRs were supplied continuously with inflow solutions containing sulfate and soluble As III or As V and, after 3 weeks, also lactate. The experiment ran for a total of 8 weeks. The dissolved iron concentration, pH, redox potential (E h ), as well as aqueous As and sulfur speciation were monitored in the outflow solutions. In FTRs containing surface sediment enriched in labile organic matter (OM), microbial sulfate reduction led to an accumulation of organically bound S, as evidenced by X-ray absorption spectroscopy. For these FTRs, the inflowing dissolved As concentration of 20 mM was lowered by two orders of magnitude, producing outflow concentrations of 0.2 mM monothioarsenate and 0.1 mM arsenite. In FTRs containing sediment collected at greater depth, sulfide and zero-valent S precipitated as pyrite and elemental S, while steady-state outflow arsenite concentrations remained near 5 mM. The observations thus suggest that As sequestration is enhanced when sediment OM buffers the free sulfide and zero-valent S concentrations. An updated conceptual model for the fate of As in the anoxic As-C-S-Fe system is presented based on the results of this study.

show abstract

“…All data were baseline-corrected and normalized to the edge jump, and the contribution of different S species to total S was deconvoluted over the 2466 to 2489 eV energy range by Gaussian curve fitting (Huffman et al, 1991;Prietzel et al, 2011;Manceau and Nagy, 2012), which was implemented using WinXAS 3.1 (Ressler, 1998). Briefly, six Gaussian functions (G1-G6), each reflecting one functionality, and two arctangent functions, one at low energy for all reduced S forms and another at higher energy for all oxidized forms, were applied for the fitting (Manceau and Nagy, 2012) (Supplemental Table S1).…”

Section: Sulfur K-edge X-ray Adsorption Near-edge Structure Spectroscopymentioning

confidence: 99%

Sulfur Speciation in an Arable Soil as Affected by Sample Pretreatments and Sewage Sludge Application

Luo

et al. 2014

Soil Science Soc of Amer J

View full text Add to dashboard Cite

Sulfur speciation under the influence of sample pretreatment and sewage sludge (SS) application in a continuously SS-amended soil was assessed by wetchemical fractionation and S K-edge XANES spectroscopy. Distinct differences in S speciation among the following pretreatments including fresh, air-drying, anoxic freeze-drying, oven-drying, and conditioning (incubation at room temperature and 75% of water holding capacity for 2 wk) were detected in both topsoils and subsoils. Air-drying significantly increased available S content but decreased C-bonded S content in the soils compared with anoxic freeze-drying. Oven-drying and conditioning pretreatments showed a similar effect on S fractions to air-drying in the soils but to a lesser extent. X-ray adsorption nearedge structure analysis showed that both reduced and intermediate organic S tended to decrease while oxidized S obviously increased in the air-dried samples. In contrast, the conditioning pretreatment facilitated the transformation of intermediate S into reduced organic S. Continuous application of SS significantly increased total soil S, C-bonded S, and residual S contents but decreased available S content in the topsoil. Meanwhile, XANES analysis indicated that reduced organic S was markedly increased (over 50% of total S) in the SS-amended topsoil. No obvious effect of the application of SS on S speciation in the subsoil was observed except for the facilitated transportation of S into lower depth. Overall, our results suggest that anoxic atmospheres during the entire pretreatment process from sampling to drying, grinding, and analysis is crucial for the accurate speciation analysis of S in soils, and the anoxic freezedrying is, therefore, highly recommended.

show abstract

Sulfur Speciation in Soil by S K-Edge XANES Spectroscopy: Comparison of Spectral Deconvolution and Linear Combination Fitting

Cited by 133 publications

References 24 publications

Mechanistic study of PFOS adsorption on kaolinite and montmorillonite

Mechanistic study of PFOS adsorption on kaolinite and montmorillonite

Arsenic binding to organic and inorganic sulfur species during microbial sulfate reduction: a sediment flow-through reactor experiment

Sulfur Speciation in an Arable Soil as Affected by Sample Pretreatments and Sewage Sludge Application

Contact Info

Product

Resources

About