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The ecological restoration project of Xikuangshan (XKS) effectively reduces environmental pollution. However, the hydrogeochemical factors and mechanisms leading to the evolution of antimony (Sb) content in shallow groundwater after ecological restoration have not been studied. In order to investigate the geochemical evolution of Sb content in shallow groundwater, 64 samples were collected before and after the ecological restoration project. The results showed Sb concentrations in shallow groundwater before and after ecological restoration were 0.006-39.160 mg/L (mean 3.501 mg/L), and 0.003-17.326 mg/L (mean 2.931 mg/L), respectively. The high Sb content before ecological restoration was mainly caused by the oxidation of Sb2 S3, dissolution of carbonate and silicate minerals, evaporation/concentration effects, and cation exchange. The weaker oxidation of Sb2 S3 and effective cleaning of the arsenic alkali residue reduced the Sb content in shallow groundwater after ecological restoration. This study provides a basis for understanding the effects of ecological restoration projects on the evolution of Sb content in shallow groundwater, and provides a new idea for solving groundwater pollution and promoting groundwater resources management. [ABSTRACT FROM AUTHOR]

To explore the feasibility of reusing solid waste to stabilize high-content arsenic (As) and antimony (Sb) tailings, red mud, fly ash, dried sludge, ferrous sulfate (FeSO4), and rice husk ash (RHA) were used as the stabilizer to stabilize the Sb tailings in Qing Long and Du Shan. The combined treatment with 5% red mud, 10% fly ash, 5% dried sludge, 1% FeSO4, and 1% rice husk ash had the best stabilization effects on As and Sb, the leaching concentrations of As and Sb decreased considerably under neutral conditions, this indicates that the leaching behavior of As and Sb is controlled by the alkaline and acid-retarding capacity of the materials. In addition, the leaching of heavy metals decreases with the formation of (C-S-H) and calcite (CaCO3), indicating that heavy metals exist in the form of metal hydration or hydroxide and precipitate on the surface of calcium silicate hydrate (C-S-H) and calcite particles. Leaching of heavy metals in stabilized materials can be considered as a pH-dependent and control process of stabilization products. [ABSTRACT FROM AUTHOR]

To investigate the heavy metal enrichment mechanisms and release characteristics of typical deposits in karst areas, the Sb tailing pond of Dachang, Qinglong, Guizhou Province, China, one of the three largest Sb mines in the word, was selected as the study area. In this study, samples were collected from tailings (0~120 cm) and analyzed for changes in Sb and As content at different pH values by simulated acid rain static release experiments, and solid waste materials (fly ash, quicklime, and zeolite powder) were selected to design an orthogonal test to explore the optimal stabilization effect of Sb and As. The results showed that the average contents of Sb and As exceeded background values of Guizhou soil to different degrees. The content of As leaching revealed slight differences in the leachate. Sb was sensitive to more acidic conditions, and its release content can pose an ecological risk. Further, the best stabilization effect of Sb and As was observed after adding different ratios of fly ash, quicklime, and zeolite powder for a period of maintenance, which can be used as promising stabilizing materials for mine tailings remediation. This study provides comprehensive theoretical support for enhancing source control and risk management of heavy metals. [ABSTRACT FROM AUTHOR]

Total concentrations and different forms of antimony (Sb) in soils of Laokuang District (LKQ-1, LKQ-2, LKQ-3), Beikuang District (BKQ-4, BKQ-5, BKQ-6) and Nankuang District (NKQ-7, NKQ-8, NKQ-9, NKQ-10) of Xikuangshan, Hunan province, China were analyzed. The soil Sb concentrations in the whole-ore heap of LKQ-1 and the mining land of NKQ-7 were up to 4258 and 3174 mg/kg respectively, which were both 2000 times above the background soil Sb level in China. In terms of vertical distribution, the Sb concentrations gradually declined with the rise of soil depth. Tessier's 5-step sequential extraction method showed Sb mainly existed in stable forms (organic-matter-bound form, residual form), and the available form accounted for 18%. The proportions of different forms ranked as residual form >iron/manganese oxides >organic-matter-bound form >carbonate-bound form > water-soluble form. Vegetation affected the form distribution of Sb in a complex way and may increase the bioavailability of Sb, so ecological restoration of Sb can be realized through the absorption by vegetation. Analysis of the geoaccumulation index and the potential ecological risk index showed that Xikuangshan was under extremely severe Sb pollution and very serious potential ecological risk. The Sb mining and smelting activities of humans aggravated local Sb pollution. [ABSTRACT FROM AUTHOR]

Studies on bacterial endophytes resistant to antimony (Sb), a pollutant deemed alarming, are virtually non-existent. An endophytic bacterial strain showing resistance to high antimony concentrations was isolated for the first time from the roots of Hedysarum pallidum Desf., a Sb accumulator Fabacea growing on mining spoils. With the combined use of morphological, biochemical and molecular methods, the isolated strain was identified as Serratia marcescens species. It showed a minimum inhibitory concentration (MIC) to its growth at 450 mM of Sb. In the presence of excessive concentrations of Sb, corresponding to 30 mM of Sb, i.e., 3652.8 mg/L of Sb, the strain maintained important growth compared to the control. The Sb toxicity caused a significant increase (p<0.05) in the hydrogen peroxide (H2O2) amount and malondialdehyde (MDA) content. The oxidative stress induced significant increases (p<0.05) in the strain antioxidant biomarkers such as proline, catalase (CAT), ascorbate peroxidase (APX), peroxidase (POD) and superoxide dismutase (SOD). Significant and positive correlations (p<0.05) were found between oxidative and antioxidant biomarkers and between antioxidant biomarkers, highlighting the interrelationships between them in oxidative stress fighting. Results show an important adaptation of the strain to high Sb levels that can be used in the Sb-contaminated soils bioremediation. [ABSTRACT FROM AUTHOR]

In this study, adsorption behaviors and mechanisms of Sb(III) ions onto Fe(III)-treated humus sludge adsorbent (FTHSA) from aqueous solutions was investigated using batch adsorption techniques, Fourier transform infrared (FT-IR) spectra and scanning electron microscopy were coupled to an energy-dispersive spectrometer (EDS). FTHSA was prepared via immersion with 1 mol/L FeCl3. The effects of dosage, contact time, Sb(III) initial concentration, and pH on the adsorption of Sb(III) onto FTHSA were investigated. Sb(III) adsorption was favored at pH with 2.0 and decreased dramatically with increasing pH. The description of equilibrium data of Sb(III) adsorption by Langmuir, Freundlich, and Dubbin-Radushkevich isotherm models showed that Langmuir model provided the best fit for Sb(III) adsorption with maximum adsorption amount of 9.433 mg/g. Pseudo first-order, pseudo second-order, Elovich, and intraparticle diffusion model were applied to describe the adsorption process of Sb(III) ions onto FTHSA. The results showed that the pseudo second-order model described well how Sb(III) adsorption and chemical adsorption played a dominant role in the adsorption process. The FT-IR spectra also indicated that the chemical interactions as ion exchange among the metal ions and N-H, O-H, C=O, COO, and C-O were mainly involved in the adsorption process. Therefore, FTHSA has a suitable potential removal for Sb(III) ions in the practical process. [ABSTRACT FROM AUTHOR]

The aim of the study was to compare accumulation capacity of selected biogenic and toxic metals (As, Cd, Cu, Pb, Sb, and Zn) in the leaves of 3 tree species (Alnus glutinosa, Salix sp., and Sambucus nigra) from 5 locations in the Malé Karpaty Mountains in the Slovak Republic near Trniansky, Stoličný, and Gidra streams. These observed locations (with accentuation to upper flows of mentioned streams) are characterized by mainly high occurrences of arsenic and antimony as a result of geological bedding and abandoned Sb mining deposits in the Pezinok area. Obtained results confirmed that each tree species in view varied in accumulation capacity for individual metals. While Salix sp. indicated in the leaves high levels of As, Cd, and Zn, Sambucus nigra accumulated from all spotted trees in the highest amounts mainly lead and antimony. The lowest cadmium accumulation was confirmed for Alnus glutinosa. Regression analysis confirmed significantly positive correlations between Pb--Cu (p<0.001), Cd--Cu (p<0.01), and Pb--Cd (p<0.01) concentrations in Alnus glutinosa leaves. However, for Sambucus nigra there was significantly positive correlation confirmed between As--Sb (p < 0.001). [ABSTRACT FROM AUTHOR]

This study takes the Southern antimony smelting slag depot in Xikuangshan (XKS) Sb mine in the city of Lengshuijiang, Hunan, China, as the research object and explores the release law of Sb, As, and Hg in smelting slag under different pH-value simulated acid rain by a semi-dynamic leaching experiment of simulating the local rain. The results show that the leachate pH value is positively correlated with the pH value of simulated acid rain, while the leachate conductivity is negatively correlated with it. The leaching rates of As and Hg are negatively correlated with the pH value of the simulated acid rain, while the leaching rate of Sb is positively correlated with it; in the leaching process, the leachate pH value goes downward slowly after shooting up, but the leachate conductivity is continuously reduced; the releasing process of Sb, As, and Hg consists of two stages, and their leaching rate forms such an order as Sb > Hg > As. The diffraction peak intensity of the main mineral composition of quartz and calcite decreases significantly after leaching; the smelting slag's surface becomes less rough than before leaching, with fewer pores and edges, and the contents of S, Si, Al, Fe, Ca, and Sb on the slag surface decrease while the content of O, As, and Hg increases. [ABSTRACT FROM AUTHOR]

The objective of this work was to verify the sorption properties of granular filter materials (GEH, CFH12, Bayoxide E33) during the process of removing antimony from water, and to monitor the impact of magnetic and electromagnetic fields on the effectiveness of removing antimony from water. Pilot tests showed that the use of iron-based sorption materials could possibly decrease the antimony content in water to the values limited for drinking water (5 μg/L Sb). The most suitable adsorbent for removing antimony was GEH. At a concentration of antimony in raw water of 81.4 μg/L and a filtration rate of 3.4 m/h, a value of bed volume 2,030 and adsorption capacity of 144.7 μg/g was determined; at the filtration rate of 5.6 m/h, the bed volume was 1,342, and the adsorption capacity was 96.8 μg/g achieved at breakthrough concentration 5 μg Sb/L. The results presented from testing the effects of a permanent magnet and electromagnet in removing antimony are not well known, as only a few experiments have been conducted. [ABSTRACT FROM AUTHOR]

Antimony (Sb) pollution in Sb mining areas has been of growing environmental concern. However, limited information is available on environmental behavior and biogeochemical process of Sb. In the present study, complexation of Sb(III) with extracellular polymeric substances (EPS) from cyanobacterium Synechocystis sp. was investigated using excitation-emission matrix (EEM) fluorescence spectroscopy. Two protein-like fluorescence peaks were identified in the EEM spectra of EPS. Fluorescence of both peaks was clearly quenched by Sb(III). The quenching constants (logKa) and the binding constants (logKb) for peaks A and B were in the range of 3.21-4.13 and 3.22-4.14, respectively. The interaction between EPS and Sb(III) is spontaneous and endothermic. The binding of Sb(III) to EPS is dominated by the hydrogen bonding and Van der waals forces. FTIR analysis showed that polysaccharides in EPS also participated in complexation EPS with Sb(III). [ABSTRACT FROM AUTHOR]

Antimony (Sb) pollution has been of growing environmental concern. Little information is available on biosorption of Sb. In the present study, biosorption behavior and mechanisms of Sb(III) to the cyanobacterium Synechocystis sp. cells were investigated by batch experiments and FTIR analysis. Our study shows that Synechocystis sp. cells are a good adsorbent for Sb(III) with a sorption capacity of 4.68 mg⋅g-1 dry weight adsorbent. The isothermal sorption data can be described by the Langmuir Isotherm and the Freundlich Isotherm. Several mechanisms were involved with biosorption of Sb to Synechocystis sp. cells and sorption to binding sites might be dominant. The sorption kinetics followed the pseudo-second order model. The adsorbed Sb is mainly located in extracellular polysaccharides (EPS) and within the cell, and a small proportion was adsorbed onto the cell wall. The proteins and polysaccharides in EPS and the polysaccharides on the cell are the main functional groups that are responsible for adsorption of Sb to Synechocystis sp. cells. [ABSTRACT FROM AUTHOR]

Flow-through stripping chronopotentiometry was used for the determination of antimony in soil samples. antimony was deposited in potentiostatic mode on a glassy carbon porous electrode coated with nafion® and mercury and then stripped with constant current. The accuracy of the results was confirmed by graphite furnace atomic absorption spectrometry. The LOD and LOQ were found to be 0.6 µg dm-3and 1.7 µg dm-3, respectively. A linear response range was observed in the concentration range of 1 to 200 µg dm-3 for sample volumes of 4 ml. The repeatability and reproducibility were found to be 2.9% and 5.2%, respectively. [ABSTRACT FROM AUTHOR]

This EPA treatment technology project was designed to collect data on the performance of existing water treatment processes in order to remove arsenic on pilot-scale. Our paper contains verification testing of the reverse osmosis membrane module conducted over a 30-day period at the Spiro Tunnel Bulkhead water (Park City, Utah, USA), which is considered to be a ground water. The total arsenic concentration in the feedwater averaged 60 ppb during the test period and was reduced to an average of 1 ppb in the treated (permeate) water. The work reported here focused on obtaining accurate readings for arsenic valence states (III) and (V), using an anion exchange resin column. The dominant arsenic species in the abandoned silver mine tunnel feedwater was as(V). Results of analysis showed that 70% of the arsenic present in the feedwater was in dissolved form. Arsenic speciation for valence states (III) and (V) showed that arsenic (V) represented 76% of the dissolved arsenic in the source water. The method detection limit (MDL) for arsenic using ICP-Ms was determined to be 0.1 ppb. Our matrix spiked recovery, spiked blank samples and reference materials deviated only a few percentage points from the listed true values. [ABSTRACT FROM AUTHOR]

This paper presents results of the determination of the total concentration of arsenic, antimony and selenium and their inorganic speciation forms in water samples from grate ashes dumping grounds. Determined concentrations of elements were up to 128.8 ng/mL for arsenic,153.7 ng/mL for antimony and 52.9 ng/mL for selenium, at the detection limits of 0.16 ng/mL for As, 0.18 ng/mL for Sb and 0.15 ng/mL for Se. Water from some study sites was characterized by very high concentrations of determined elements, which were used to follow their migration. Leakage of dangerous micro-pollutants to ground water was stated. Based on results of speciation analysis the vertical migration of pollutants through unsaturated zone was found. [ABSTRACT FROM AUTHOR]

This study was aimed at recognizing the levels of arsenic, antimony and selenium concentrations in different zones of the lake ecosystem. Total content as well as inorganic species of the studied metalloids were considered. Shallow Lake Jaroslawieckie (Wielkopolski National Park) was chosen for the study reported. Water samples were collected in different macrophyte communities of the phytolittoral and in the middle of the lake in early spring and mid-summer 2002. Total concentrations of all studied metalloids in samples collected in summer were lower than in those collected in spring but not all studied mineral species of As, Sb and Se followed the same pattern of changes. Despite seasonal changeability the lack of significant spatial differentiation in the concentrations of the elements studied at the peak of the vegetation season, in particular no differences in their concentrations between the sites in the bulk water in the middle of the lake and the sites in the plant communities was stated. This finding might testify to the fact that the effect of vegetation on the concentration of the elements studied is limited. [ABSTRACT FROM AUTHOR]

This paper presents a comparative description of different methods of determination of arsenic, antimony and selenium: spectrophotometric, electro-analytical (voltamperometry), activation analysis, atomic fluorescence and the methods of inductive or microwave-induced plasma in combination with different detection methods (emission or mass spectrometry). The description is based on literature data illustrating the present state of the metalloid determinations in different matrices. The limits of determination ensured by different methods are also compared. Much attention has been paid to methods combining chromatographic separation with selective detection, especially with the application of plasma generation methods (usually ICP-MS). [ABSTRACT FROM AUTHOR]

This paper reports results of determination of arsenic, antimony and selenium inorganic species in samples of surface water from the lakes of the Pszczewski Landscape Park located in western Poland. Concentrations of total arsenic, antimony and selenium, determined by atomic absorption spectrometry with generation of hydrides, were up to 0.66 ng/ml, 0.62 ng/ml and 0.76 ng/ml, respectively, at respective detectability limits of 0.04 ng/ml, 0.04 ng/ml and 0.03 ng/ml. For arsenic and antimony the concentrations of the two species determined (As(III)/As(V) and Sb(III)/Sb(V) were similar, while for selenium the Se(IV)species was dominant. [ABSTRACT FROM AUTHOR]

This paper presents results of determination of the total content of arsenic, antimony and selenium in samples of surface water from selected lakes of Pszczewski Landscape Park. The concentrations of arsenic, antimony and selenium determined by the absorption atomic spectrometry method were up to 0.66 ng/ml, 0.62 ng/ml and 0.76 ng/ml, respectively, at the detection limits of 0.04 ng/ml for As, 0.04 ng/ml for Sb and 0.03 ng/ml for Se. The water samples studied revealed low concentrations of the elements of interest relative to the values obtained for the samples from other regions. The determined concentrations of arsenic, antimony and selenium can be interpreted as natural. [ABSTRACT FROM AUTHOR]

This paper reports determination of arsenic, antimony and selenium in different matrices using atomic absorption spectrometry, with atomisation in a graphite tube and with generation of hydrides. The actual state of atomic absorption spectrometry as the method of determining As, Sb and Se is described on the basis of literature data. The effects of interference in determinations by atomic absorption spectrometry, and the problems related to sample preparation to determinations (extraction, mineralisation, concentration) are discussed. The application of flow injection analysis in atomic absorption spectrometry with hydride generation is described. The effectiveness of atomic absorption spectrometry in speciation determinations of arsenic, antimony and selenium applied alone and in combination with chromatographic methods is shown. [ABSTRACT FROM AUTHOR]

This paper shows speciation analysis of arsenic, antimony and selenium using hydride generation atomic absorption spectrometry. Determining different forms of given elements (forms on different oxidation stages: As(III)/As(V), Sb(III)/Sb(V), Se(IV)/Se(VI) and forms bound with organic matter) is based on different kinetics of hydride generation for forms on different oxidation degrees. This paper shows steps for speciation analysis as described in literature, the main procedures and reagent used in different studies. [ABSTRACT FROM AUTHOR]

Presents a study which determined the total amounts of arsenic, antimony and selenium macrocomponents in water samples. Experimental procedures; Methodology; Results and discussion.

Deals with a study which presented statistical analysis of the total content of arsenic, antimony and microcomponents from a groundwater in Wielkopolska, Poland. Discussion on the arsenic content of water; Materials and methods used; Results and discussion.