Trace Tl Research Articles

Highly efficient removal of trace thallium from surface water by Co@Fe Prussian blue analogue coated membrane

Super trace thallium(I) (Tl+) is still highly toxic and its removal from surface water is challenging. Here, we developed a new adsorptive membrane by immobilizing bimetal (cobalt and iron) Prussian blue analogues (Co@Fe-PBAs) on a polytetrafluoroethylene microporous membrane (Co@Fe-PBAs-M). The prepared membrane displayed precise adsorption of trace Tl+ (50 μg/L) from complex water. A variety of interfering factors, such as water pH, competitive adsorption of positive ions (Na+ and K+) and negative ions (CO32– and PO43-), natural organic matters (e.g., fulvic acid and bovine serum albumin) were evaluated during Tl removal. The composite membrane showed high removal efficiency (over 80 %) during long-term dynamic membrane separation of surface water containing super trace Tl+ (<2.0 μg/L), breaking through the adsorption limitation in ultralow concentration of Tl+. The unique bimetal electron transfer of Co@Fe-PBAs-M reinforced the adsorptive performance to Tl+ through dual ion exchange and intercalation. In the treatment of real Pearl River water containing 0.5 μg/L of Tl+, our membrane effectively reduced the Tl+ concentration to 0.04 μg/L during 6-h continuous separation, which was far below the required level for drinking water (i.e., 0.1 μg/L). This work offers a promising solution for safe drinking water by remedying ultralow Tl+ contaminated surface water.

Enhanced removal of trace thallium by photo-promoted adsorption using Prussian blue@filter papers: Performance and mechanistic insights

Developing highly efficient adsorbents for the removal of trace thallium(I) (Tl+) is crucial for addressing environmental challenges. In this study, we successfully synthesized cubic Prussian blue (PB) loading on filter papers using an intermediate layer (dopamine/polyethyleneimine) via in-situ methods. The as-prepared PB-modified FP demonstrated outstanding anti-interference properties and light-enhanced adsorption performance for Tl+ (0.5 mg/L) under ultraviolet (UV) irradiation, exhibiting twice the effectiveness compared to dark conditions, even in acidic and coexisting ionic environments. This indicated its suitability for treating complex Tl+-contaminated water. Notably, the removal efficiency for trace Tl+ was almost 100%, with a maximum experimental adsorption capacity of 86.2 mg/g after 1-h photo-promoted adsorption under 365 nm UV. Characterization results supported a proposed photo-driven redox mechanism that elucidated the interaction between Tl+ and PB-modified FP. Specifically, the accelerated Fe(III) to Fe(II) redox reaction facilitated Tl+ accommodation on the surface and/or lattice of PB, enhancing Tl+ adsorption by compensating for missed positive charges. This study provides valuable insights into utilizing PB-based materials to enhance the photo-enhanced Tl+ adsorption capacity in a cost-effective, easy-to-synthesize, and environmentally friendly manner.

Electro-induced biochar-embedded-SIPN hydrogel as discrete bipolar electrodes for selective oxidation and enrichment of trace thallium(Ι)

Electrochemical techniques for thallium (Tl) treatment face a substantial challenge linked to the concentration of Tl(I), hindering the efficient removal and recovery of trace Tl(I) (μg L−1). In response, we synthesized hydrogel particles incorporating biochar (BC) within semi-interpenetrating polymer networks (SIPN), showcasing robust selectivity for Tl(I). These biochar-embedded-SIPN hydrogel particles (BC-SIPN particles), employed as dispersed electrodes, facilitated the targeted oxidation and enrichment of Tl(I) through electro-induction. Research outcomes elucidate the adept mitigation of the “efficiency-dependent concentration” behavior by electro-induced BC-SIPN particles during the reaction process. Under optimized conditions (pH 12, 2 V cm−1, 30 min), Tl(I) removal efficiency surpassed 98 % at an initial concentration of 100 μg L−1. The SIPN structure enhanced particle stability, and after seven cycles of enrichment in a 100 μg L−1 Tl(I) environment, BC-SIPN particles achieved a Tl content of 0.073 %, meeting Tl mineral content standards and promoting the recovery of scarce Tl resources. First-principles calculations underscore the pivotal role of hydrogen bond-electrostatic interactions between TlOH(aq) and particles in driving selective Tl(I) adsorption. Insights from quenching and capture reactions reveal a predominant direct oxidation pathway of Tl(I) to Tl(Ⅲ), complemented by indirect oxidation driven by reactive oxygen species, including OH, O- 2 and 1O2. This study presents an innovative approach for trace Tl(I) wastewater treatment, simultaneously mitigating the “efficiency-dependent concentration” phenomenon, and underscores the transformative potential of electro-induced BC-SIPN hydrogel particles in offering sustainable solutions for Tl(I) removal and resource recovery in environmental stewardship.

Magnetic Prussian Blue nanosorbent loading on sepiolite for specific removal of Tl(I)

Thallium, a highly toxic trace element, being released into the environment by industrial mining has caused serious environmental pollution. Here, a magnetic Prussian Blue (PB) nanosorbent loading on sepiolite (PB/Fe3O4/SEP) was successfully synthesized for the deep treatment of Tl(I) based on its high adsorption capacity. The high adsorption capacity of up to 558 mg/g helps the nanosorbents efficient adsorption of trace Tl(I) in wastewater. Then the strong magnetic help convenient removal from wastewater. Moreover, its excellent anti-disturbance properties in a wide range of pH indicated that it is suitable for complex wastewater treatments. Overall, the magnetic nanocomposite with excellent adsorption properties and high interference resistance can be applied for emergency treatment in actual Tl(I) contaminated water.

High-efficiently capturing trace thallium (Ι) from wastewater via the prussian blue@polytetrafluoroethylene hybrid membranes

The exploitation of advanced material technology with high selectivity, efficiency, and separability for thallium (Tl) removal remains challenging. In this work, a hybrid polytetrafluroethylene membrane with polydopamine (PDA)/polyethyleneimine (PEI) co-supported Prussian blue nanoparticles (PB NPs) was successfully fabricated and denoted as PB@PDA/PEI-M−1. The PB@PDA/PEI-M−1 displayed a high-efficient capture for Tl(I) during a continuous flowing operation. Based on the pseudo-second-order model, its dynamic Tl(I)-adsorption constant (k) and maximum capacity (qe) are 1.8 min−1 and 460.4 mg/m2 respectively, which are both much higher than the static adsorption and many previous studies. Tl(I)-adsorption capacity of PB@PDA/PEI-M−1 was slightly decreased by the disturbances of many accompanying impurity ions (H+, Ca2+ or Mg2+), but it still reached a high level. The density functional theory (DFT) revealed the most prominent binding ability of membrane surface-loaded PB with Tl(I) via ion exchanges, contributing to the high selectivity of PB@PDA/PEI-M−1 in capturing trace Tl(I). As for the macromolecular organic matter, humic acid (HA) facilitated the Tl(I)-capture ability of PB@PDA/PEI-M−1 due to the formation of Tl-HA complexes and their high adsorption on membrane surface. By virtue of those advantages, our as-prepared membranes exhibit excellent ability in remedying the actual Tl(I)-polluted pearl river water, and in the meantime, membrane structure robustness was well maintained. All results verified that PB@PDA/PEI-M−1 provided a feasible technology for Tl(I) removal in a complicated environment.

Enhanced Trace Tl Removal with Ferrate through the Addition of Mn(II): Effect and Mechanism

Thallium (Tl) is highly toxic and mobile compared with the other priority pollutant metals, and trace Tl pollution is difficult to control. Some mineral deposits in South China contain high levels ...

Cu-Based MOF for Simultaneous Determination of Trace Tl (I) and Hg (II) by Stripping Voltammetry

In this study, blue octahedral crystal of Cu-based metal-organic framework (Cu-MOF) was synthesized through a simple solvothermal method. The Cu-MOF was used as a modifier on GCE for the simultaneous determination of Tl (I) and Hg (II) at the trace level by square wave anodic stripping voltammetry (SWASV). The synthesized Cu-MOF was characterized by scanning electron microscope (SEM), transition electron microscope (TEM), X-ray diffraction (XRD), and electrochemical impedance spectroscopy (EIS). The parameters affecting the electrochemical process, such as the kind of electrolyte solution, KCl concentration, the potential, and the time for accumulation were investigated in detail. Under the optimal conditions, the present sensor showed excellent electrochemical performance for Tl (I) and Hg (II) in the leaner ranges from 0.5–700 ppb and 1–400 ppb, respectively. Low detection limits of 0.11 ppb for Tl (I) and 0.17 ppb for Hg (II) were achieved. The method is successfully applied to the determination of Tl (I) and Hg (II) in real samples and good recoveries are obtained from different spiked samples.

Determination of Trace Tl(I) by Differential Pulse Anodic Stripping Voltammetry Using a Novel Modified Carbon Paste Electrode

In this study, novel modifiers composed of multi walled carbon nanotubes (MWCNTs) and a series of noncyclic crown-type polyethers were prepared. The ligand loaded MWCNTs along with a room temperature ionic liquid (RTIL) 1-butyl-3-methylimidazolium hexafluoro phosphate ([bmim][PF6]) were used for modification of a simple and low-cost carbon paste electrode (CPE). The modified CPE was employed for the determination of thallium(I) in aqueous medium using differential pulse anodic stripping voltammetry (DPASV) method. The effect of different experimental conditions such as supporting electrolyte, solution pH, accumulation potential, accumulation time, and modifier dosage were investigated and optimized. By DPASV, a linear dynamic range of 0.3–70 μg l−1 was achieved. The detection limit (3Sb) was found to be 0.08 μg l−1, below the maximum allowable limit (2 μg l−1) of the U.S. Environmental Protection Agency (USEPA). The present assay was also showed acceptable reproducibility with a relative standard deviation (RSD) value of 3.8% at 25.0 μg l−1 level (n = 7). The applicability of this electrode was successfully explored by measuring of thallium(I) in some natural waters without interference from sample matrix.

Relationship Between Major And Trace Elements In Ulaanbaatar Soils: A Study Based On Multivariate Statistical Analysis

This article focuses on the relationships between major (Si, Al, Mg, Fe, Ca, Na, K, S, P and Ti) and potentially toxic trace (Ag, As, B, Ba, Bi, Co, Cd, Cr, Cu, F, Ge, Mo, Mn, Li, Ni, Pb, Sb, Sn, Sr, Tl, V and Zn) elements in Ulaanbaatar surface soils and also sources of the trace elements in the soils distinguished by the methods of multivariate statistical analysis. Results of exploratory data analysis of 325 Ulaanbaatar soil samples show the accumulation of Ca, S, B, Bi, Cu, Mo, Pb, Sb, Sn, Sr and Zn in urban soils. The major elements were grouped by cluster analysis in tree associations characterizing main soil fractions: sandy P-(K-Na-Si), clayey (Mg-Ti-Fe-Al) and silty (S-Ca). The factor analysis shows that silty fraction is enriched in major elements of both natural and anthropogenic origin. The principal component analysis from 32 variables extracted nine principal components with 82.49% of the cumulative explained variance. The results of cluster and factor analyses well agree and reaffirm the enrichment causes of potentially toxic elements are a coal combustion at thermal power stations (B, Bi, Ca, Mo, S and Sr) and traffic emissions (Cu, Pb, Sn and Zn). Spatial distributions of trace elements in the districts of Ulaanbaatar city were obtained by ordinary kriging. It is illustrated that the different principal components define the various origins and patterns of accumulation of trace elements in soils. The supplementation of data set by the concentration of organic carbon and the species of elements could help to identify the sources of such elements as P, Ni, Al, Fe, Ca, Ba, Bi, Cr, Zn, Sr and Sb in urban soils more completely.

Treatment of trace thallium in contaminated source waters by ferrate pre-oxidation and poly aluminium chloride coagulation

Thallium (Tl) was released into the environment through growing human activities, and removing trace Tl from polluted source water is a severe challenge. This work demonstrated that by combining K2FeO4 pre-oxidation with poly aluminum chloride (PAC) coagulation, removal efficiency of trace Tl [including Tl(I) and Tl (III)] in source waters could be substantially elevated. Compared with KMnO4 pre-oxidation, K2FeO4 pre-oxidation is more effective on Tl removal. Over 87% of total-Tl (initial concentration: 0.76 μg/L) was removed by 3 mg/L K2FeO4, and the residual Tl was below 0.1 μg/L. Compared with Tl(I), Tl(III) was easier to be removed by K2FeO4. Efficiency of K2FeO4 pre-oxidation combined with activated carbon adsorption on Tl removal is limited, while PAC coagulation could enhance the removal of Tl with K2FeO4 pre-oxidation. K2FeO4 + PAC treatment could effectively attenuate the leakage of Tl from settled floc as well. Effects of background constituents and operation procedures on Tl removal were investigated, and optimized operation procedures were explored. Our findings suggest that K2FeO4 pre-oxidation combined with PAC coagulation could be an effective method for the control of trace Tl in contaminated source water.

Statistical Evaluation of Soil Geochemical Data from Dagbala-Atte District in Igarra Schist Belt, Southwestern Nigeria

The results of 27 trace elements, namely, Ag, As, Au, Ba, Bi, Cd, Co, Cr, Cu, Fe, Ga, Hg, La, Mn, Mo, Ni, Pb, Sb, Sc, Se, Sr, Te, Th, Tl, U, V and Zn in 49 soil samples collected on a uniform 3 km × 2 km grid pattern over Dagbala-Atte District were subjected to some univariate and multivariate statistical evaluation. The univariate methods used include frequency distribution and dispersion boxm plots while the multivariate methods employed are correlation and factor analyses. Frequency distribution and dispersion box plots revealed that most elements showed mixtures of populations and are log-normally distributed in varying degrees at 95% confidence level. Eventually, the univariate statistics was applied to compute the threshold values for all the elements in the District, whichm allowed the determination of anomalous concentration for each element. Pearson correlation coefficients indicate fair to very good correlation between pairs of elements. Four factors, similar to the subjective groupings obtained from the correlation matrix, were derived from R-mode factor analysis. This four-factor model has been interpreted as reflecting underlying lithology, potential mineralization and physico-chemical conditions in the environment. Results of a study of the correlation matrix and factor analysis of the soil geochemical data from Dagbala-Atte District indicate that most of the anomalous values of the elements could be attributed to mineralization such as U-Th in rare-metal pegmatite in the northeastern part of the district underlain by granitic-gneiss, Cu-Ni mineralization associated with minor Au at the boundary between the granitic gneiss and the metasediments, and base metal (Pb- Zn) and Ag mineralization, possibly in form of minor veins, in the southwestern part of the district underlain by metaconglomerate.

Thallium Adsorption onto Illite.

We investigated the adsorption of Tl+ onto purified Illite du Puy (IdP). Distribution coefficients (Kd) for trace Tl adsorption indicated a moderate pH-dependence from pH 2.5 to 11. Adsorption isotherms measured at Tl+ concentrations from 10-9 to 10-2 M at near-neutral pH on illite saturated with Na+ (100 mM), K+ (1 and 10 mM), NH4+ (10 mM) or Ca2+ (5 mM) revealed a high adsorption affinity of Tl+ in Na+- and Ca2+-electrolytes and strong competition with K+ and NH4+. Cation exchange selectivity coefficients for Tl+ with respect to Na+, K+, NH4+, and Ca2+ were derived using a 3-site sorption model. They confirmed the strong adsorption of Tl+ at the frayed edges of illite, with Tl selectivity coefficients between those reported for Rb+ and Cs+. X-ray absorption spectra of Tl adsorbed onto Na-exchanged IdP indicated a shift from adsorption of (dehydrated) Tl+ at the frayed edges at low loadings to adsorption of (hydrated) Tl+ on planar sites at the highest loadings. Our results suggest that illite is an important adsorbent for Tl in soils and sediments, considering its often high abundance and its stability relative to other potential adsorbents and the selective nature of Tl+ uptake by illite.

Effective removal of trace thallium from surface water by nanosized manganese dioxide enhanced quartz sand filtration

Thallium (Tl) has drawn wide concern due to its high toxicity even at extremely low concentrations, as well as its tendency for significant accumulation in the human body and other organisms. The need to develop effective strategies for trace Tl removal from drinking water is urgent. In this study, the removal of trace Tl (0.5 μg L−1) by conventional quartz sand filtration enhanced by nanosized manganese dioxide (nMnO2) has been investigated using typical surface water obtained from northeast China. The results indicate that nMnO2 enhanced quartz sand filtration could remove trace Tl(I) and Tl(III) efficiently through the adsorption of Tl onto nMnO2 added to a water matrix and onto nMnO2 attached on quartz sand surfaces. Tl(III)-HA complexes might be responsible for higher residual Tl(III) in the effluent compared to residual Tl(I). Competitive Ca2+ cations inhibit Tl removal to a certain extent because the Ca2+ ions will occupy the Tl adsorption site on nMnO2. Moreover, high concentrations of HA (10 mgTOC L−1), which notably complexes with and dissolves nMnO2 (more than 78%), resulted in higher residual Tl(I) and Tl(III). Tl(III)-HA complexes might also enhance Tl(III) penetration to a certain extent. Additionally, a higher pH level could enhance the removal of trace Tl from surface water. Finally, a slight increase of residual Tl was observed after backwash, followed by the reduction of the Tl concentration in the effluent to a “steady” state again. The knowledge obtained here may provide a potential strategy for drinking water treatment plants threatened by trace Tl.

Highly efficient removal of trace thallium from contaminated source waters with ferrate: Role of in situ formed ferric nanoparticle

Thallium (Tl) is highly toxic to mammals and relevant pollution cases are increasing world-widely. Convenient and efficient method for the removal of trace Tl from contaminated source water is imperative. Here, the removal of trace Tl by K2FeO4 [Fe(VI)] was investigated for the first time, with the exploration of reaction mechanisms. Six different types of water treatment agents (powdered activated carbon, Al2(SO4)3, FeCl3, δ-MnO2, MnO2 nano-particles, and K2FeO4) were used for the removal of Tl in spiked river water, and K2FeO4 showed excellent removal performance. Over 92% of Tl (1 μg/L) was removed within 5 min by applying 2.5 mg/L of K2FeO4 (pH 7.0, 20 °C). XPS analysis revealed that in the reaction of Tl(I) with K2FeO4, Tl(I) was oxidized to Tl(III), and removed by the K2FeO4 reduced ferric particles. The removal of Tl by in situ formed and ex situ formed ferric particle was examined respectively, and the results revealed that the removal of trace Tl could be attributed to the combination of adsorption and coprecipitation processes. The hydrodynamic size of the reduced particle from K2FeO4 ranged from 10 nm to 100 nm, and its surface was negatively charged under neutral pH condition. These factors were conducive for the efficient removal of Tl by K2FeO4. The effects of solution pH, coexisting ions (Na+, Ca2+, and HCO3−), humic acid, solution temperature, and reductive environment on the removal and desorption of Tl were investigated, and the elimination of Tl in polluted river water and reservoir water was performed. These results suggest that K2FeO4 could be an efficient and convenient agent on trace Tl removal.

Constructed ILs coated porous magnetic nickel cobaltate hexagonal nanoplates sensing materials for the simultaneous detection of cumulative toxic metals

The different morphologies of magnetic nickel cobaltate (NiCo2O4) electrocatalysts, consisting of nanoparticles (NiCo2O4-N), nanoplates (NiCo2O4-P) and microspheres (NiCo2O4-S) were fabricated. It was found that the electrocatalytic properties of the sensing materials were strongly dependent on morphology and specific surface area. The porous NiCo2O4 hexagonal nanoplates coupled with ILs as modified materials (ILs@NiCo2O4-P) for the simultaneous determination of thallium (Tl+), lead (Pb2+) and copper (Cu2+), exhibited high sensitivity, long-time stability and good repeatability. The enhanced electrocatalytic activity was attributed to relatively large specific surface area, excellent electronic conductivity, and unique porous nanostructure. The analytical performance of the constructed electrode on detection of Tl+, Pb2+ and Cu2+ was examined using differential pulse anodic stripping voltammetry (DPASV). Under optimal conditions, the electrode showed a good linear response to Tl+, Pb2+and Cu2+ in the concentration range of 0.1–100.0, 0.1–100.0 and 0.05–100.0μg/L, respectively. The detection limits (S/N=3) were 0.046, 0.034 and 0.029μg/L for Tl+, Pb2+ and Cu2+, respectively. The fabricated sensor was successfully applied to detect trace Tl+, Pb2+ and Cu2+ in various water and soil samples with satisfactory results. Hence, this work provided a promising material for electrochemical determination of cumulative toxic metals individually and simultaneously.

Significantly improving trace thallium removal from surface waters during coagulation enhanced by nanosized manganese dioxide

Thallium (Tl) is an element of high toxicity and significant accumulation in human body. There is an urgent need for the development of appropriate strategies for trace Tl removal in drinking water treatment plants. In this study, the efficiency and mechanism of trace Tl (0.5 μg/L) removal by conventional coagulation enhanced by nanosized manganese dioxide (nMnO2) were explored in simulated water and two representative surface waters (a river water and a reservoir water obtained from Northeast China). Experimental results showed that nMnO2 significantly improve Tl(I) removal from selected waters. The removal efficiency was dramatically higher in the simulated water, demonstrating by less than 0.1 μg/L Tl residual. The enhancement of trace Tl removal in the surface waters decreased to a certain extent. Both adjusting water pH to alkaline condition and preoxidation of Tl(I) to Tl(III) benefit trace Tl removal from surface waters. Data also indicated that competitive cation of Ca2+ decreased the efficiency of trace Tl removal, resulting from the reduction of Tl adsorption on nMnO2. Humic acid could largely low Tl removal efficiency during nMnO2 enhanced coagulation processes. Trace elemental Tl firstly adsorbed on nMnO2 and then removed accompanying with nMnO2 settling. The information obtained in the present study may provide a potential strategy for drinking water treatment plants threatened by trace Tl.

Solid phase characterization and metal deportment in a mussel shell bioreactor for the treatment of AMD, Stockton Coal Mine, New Zealand

The Stockton Coal Mine, located on the West Coast of New Zealand, is evaluating the use of a mussel shell bioreactor (MSB) to treat acidic metalliferous runoff from acid forming overburden. This novel approach is similar in concept to vertical flow wetlands (VFWs) and successive alkalinity producing systems (SAPS). The MSB system is a trapezoidal pit 2 m deep, 35 m long, 3–10 m wide with 60° angle sides. During operation it contained 160 tonnes (240 m3) of mussel shell material and was saturated with a 100–200 mm water cap. Influent flowed through the reactor at a mean rate of 0.3 L s−1 resulting in a hydraulic retention time (HRT) of ≈6 days. The prototype MSB was in operation for a total of 1027 days, from June 2009 through March 2012, and effectively sequestered 99.7% of Al, 99.3% of Fe, 98.8% of Ni, 98.4% Tl and 99.3% of Zn, as determined from a previous evaluation of MSB performance. The MSB also effectively neutralized acidity, which resulted in an increase in influent pH from 2.8 to 6.9 in the effluent. Based on an examination of several excavated pits, five distinct reaction zones developed within the MSB. The reaction zones consisted of an allochthonous sediment layer (0–330 mm), an oxidized iron-rich ocherous layer (at 330–350 mm depth), an aluminum layer (at 350–600 mm depth) with geochemical variations throughout (350–500 mm and 500–600 mm); and a chemically reduced bottom shell layer (at 600–1100 mm). Representative samples were collected from each layer and analyzed using a combination of geochemical and physical methods to assess the stability of the secondary minerals and trace metal deportment within the MSB. Major elements Fe, Al, Ni, Tl, and Zn where preferentially associated with particular layers within the MSB. Elevated concentrations of Fe (110,000 mg kg−1) were observed in the allochthonous sediment and ocherous precipitate layers, while Al (27,816 mg kg−1), Ni (55 mg kg−1), and Zn (655 mg kg−1) were elevated within the aluminum and lower reduced depths within the MSB. Trace Tl (21 mg kg−1) showed varying concentrations throughout the MSB, but was strongly correlated to lower layers of the system. Microbial biofilms were observed within the reduced portions of the shell layers often proximal to bacterial shaped sulfides. The geochemical assessment of the MSB presented in this study is the first of its kind for a MSB, and supports the argument that this system is another viable option for passive treatment of AMD.

Zróżnicowanie zawartości pierwiastków śladowych w osadach torfowisk Otalżyno, Huczwa i Stoczek

VARIABILITY OF TRACE ELEMENT CONCENTRATIONS IN THE DEPOSITS OF THE OTALŻYNO , HUCZWA AND STOCZEK PEAT BOGS Abstract. Studies of peat from three peat bogs (Otalzyno bog, Huczwa and Stoczek fens) were conducted. In peat samples, after the total acid digestion, the content of trace (Li, Be, As, Se, Rb, Ag, Sb, Cs, Tl, Th, U, Ba, Cd, Co, Cr, Cu, Hg, Mo, Ni, Pb, Sn, Sr, Ti, V and Zn) and major (Al, S, Ca, Fe, K, Mg, Mn, Na, P and TOC) elements were determined. The lowest contents of trace elements were found in the raised peat bog Otalzyno. The peat from the Stoczek fen shows the highest contents of trace elements. Differences in the content of elements in the peat are strictly dependent on the chemistry of the rocks occurring in the area surrounding the bog. Trace elements display a significant correlation with the content of Al, Fe and S, a weaker correlation with P, even slightly weaker with Ca, and the weakest with TOC.

An eco-friendly cellular phase microextraction technique based on the use of green microalgal cells for trace thallium species determination in natural water samples

The selective biosorption of Tl(iii) species on green microalgal cells as a fundamental strategy for developing an efficient microextraction procedure for trace Tl speciation analysis in water samples.

Tin film sensor with on-chip three-electrode configuration for voltammetric determination of trace Tl(I) in strong acidic media

The present work describes the trace analysis of Tl(I) in acidic medium (0.05molL−1 nitric acid) by square wave anodic stripping voltammetry (SWASV) at a tin film sensor with novel configuration. This “green” electroanalytical device features on-chip metal film electrodes (a Sn-film working electrode, a Ag-film reference electrode and a Pt-film counter electrode), fabricated by sputtering the respective metals on a silicon chip. The effect of preconcentration time, preconcentration potential and SW stripping parameters on the Tl(I) detection was studied in detail. The limit of detection for Tl(I) was 1.1μgL−1, while the % relative standard deviation at the same sensor was 5.2% at the 10μgL−1 level. Finally, the sensors were successfully applied to the direct determination of Tl(I) in an acidified certified lake water sample.