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1

Investigations of sequential extraction of chromium from soil

100%
Kalembkiewicz J., Soco E.
Polish Journal of Environmental Studies
|
2002
|
tom 11
|
nr 3
The sequential extraction of Cr from soil to soil eluates was studied. The influence of conditions of soil sample preparation and conditions of eluates obtained in the final result of Cr extraction from soil and its determination were found. Conditions protecting the total extraction of Cr from soil to solutions were established.
2

Sequential extraction of chromium from galvanic wastewater sludge

100%
Bielicka A., Bojanowska I., Wisniewski A.
Polish Journal of Environmental Studies
|
2005
|
tom 14
|
nr 2
The sequential extraction of chromium from galvanic wastewater sludge was studied. A five-step sequential fractionation scheme was used to partition the chromium into exchangeable (F I), acid-soluble (F II), reducible (F III), organic matter (F IV) and residual (F V) fractions. The results of investigations indicate that 59.5% of chromium occurred in residual fraction, which is permanently immobilized, whereas 40.5% of chromium in galvanic wastewater sludge can be released to ecosystems under changing natural conditions.
3

A comparative study of sequential extraction procedures for manganese speciation in soils

100%
Kalembkiewicz J., Sitarz-Palczak E.
Polish Journal of Soil Science
|
2002
|
tom 35
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nr 2
4

Research on aluminium speciation in poor forest soils using the sequential extraction method

88%
Walna B., Siepak J., Drzymala S., Sobczynski T.
Polish Journal of Environmental Studies
|
2005
|
tom 14
|
nr 2
Research on aluminium speciation was performed using a slightly modified version of Tessier’s procedure. The soils under study displayed strongly acidic character (pH KCl of 3.3 - 4.4). The content of aluminium in the exchangeable (11 mg/kg), acid extractable (67 mg/kg), oxidizable (2650 mg/kg), reducible (658 mg/kg) and residual fraction (24,680 mg/kg) varied widely. The percentage of labile phase (sum minus residual) obtained for mean values in the profile amounted to 12.1%, which may indicate its considerable bioavailability. The soil profile under study displayed a lithogenically dichotomous structure, which was also reflected in the aluminium content in the particular fractions.
5

Heavy metal speciation in sewage sludge

88%
Jakubus M., Czekala J.
Polish Journal of Environmental Studies
|
2001
|
tom 10
|
nr 4
Sewage sludge is a rich source of organic matter and nutrients, so there is a possibility of their broader agricultural utilization. However, agricultural utilization of this material is limited by excessive quantities of heavy metals. In accordance with this, the current paper presents the results of investigations referring to the speciation of heavy metals in selected sewage sludge. It was found that there were differences among metals in the preferential formation of bonds, but also such phenomena occurred in the individual sludge samples for the same element. This was mainly observed for cadmium and nickel. Especially important are the amounts of metals associated with water soluble plus exchangeable fraction (1 mol.L-1 NH4NO3) as well as fraction of metals extracted by 1 mol.L-1 NH4OAc (pH = 6.0), corresponding to weakly adsorbed and bound with carbonates and labile organic compounds. With reference to this, it was stated that the percentage share of such combinations decreased in the order: Cu < Cr < Zn < Cd < Ni, reaching values of 2.9, 7.2, 8.8, 19.5 and 21.6% respectively. It shows those copper forms the lowest number of fast released combinations, whereas Ni and Cd - the highest.
6

Speciation of heavy metals in bottom sediments of lakes

88%
Zerbe J., Sobczynski T., Elbanowska H., Siepak J.
Polish Journal of Environmental Studies
|
1999
|
tom 08
|
nr 5
The work reported in this paper deals with the content of trace metals (Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) in bottom sediments of Goreckie Lake, situated in Wielkopolski National Park, Western Poland. Apart from total concentration, the distribution of the above metals into five fractions: exchangeable, bound to carbonates, bound to Fe-Mn oxides, bound to organic matter, and residual was studied by means of an analytical procedure involving sequential chemical extractions.
7
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Distribution of nickel fractions in forest Luvisols in the south Podlasie Lowland

75%
Pakula K., Kalembasa D.
Journal of Elementology
|
2009
|
tom 14
|
nr 3
517-525
Sequential extraction methods enable identification of chemical fractions of heavy metals in soil environment as well as evaluation of their availability and potential toxicity to biotic elements of a trophic chain. The study aimed at separating nickel fractions from particular genetic horizons of forest Luvisols by means of three sequential extraction methods (modified Tessier’s, Zeien and Brümmer’s as well as Hedley’s with Tiessen and Moir’s modifications methods), and to compare the metal content in four fractions: easily soluble, exchangeable, organic, and residual, along with their distribution within studied soils’ profiles. Nickel concentrations in the examined fractions varied: the largest amounts of the heavy metal (regardless of the analytical procedure applied) were found in residual fraction Fresid (mineral horizons) and organic fraction Forg (forest litter horizons – Ol), while the smallest ones occurred in easily soluble fraction F1 (all genetic horizons). Statistical processing revealed significant dependences between the four nickel fractions as well as between the fractions and selected properties of analyzed soils (except soil pH and total nickel content Nit).
8

Mercury fractionation in sediments of the Lower Vistula River [Poland]

75%
Boszke L., Kowalski A.
Oceanological and Hydrobiological Studies
|
2007
|
tom 36
|
nr 3
9

Speciation of heavy metals in bottom sediments of lakes in the area of Wielkopolski National Park

75%
Sobczynski T., Siepak J.
Polish Journal of Environmental Studies
|
2001
|
tom 10
|
nr 6
This paper reports results of speciation analysis of selected heavy metals (Fe, Mn, Zn, Ni, Cu, Pb, Cd) in bottom sediment samples collected from 11 lakes in the area of Wielkopolski National Park, which is a protected area subjected to limited anthropogenic factors, The main aim of the study was determination of the distribution of the metals among five speciaiton forms defined by Tessier: exchangeable, bound to carbonates, bound to hydrated oxides of iron and manganese, bound to organic matter and others. The particular forms were isolated by sequential extraction..
10

Extraction removal of lead from soil

75%
Korolewicz T., Turek M., Ciba J.
Archiwum Ochrony Środowiska
|
2000
|
tom 26
|
nr 1
11
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Heavy metals in municipal sewage sludge – a brief characteristic of potential threats and methods used to assess the ecological risk

63%
Tytla M., Widziewicz-Rzonca K.
Environment, Earth and Ecology
|
2021
|
tom 5
|
nr 1
12

Environmental constraints of phosphorus management in agriculture

63%
Leinweber P.
Nawozy i Nawożenie
|
2002
|
tom 04
|
nr 4[13]
13

Determination of heavy metal contamination in roadside surface soil by sequential extraction

63%
Isen H., Altundag H., Keskin C. S.
Polish Journal of Environmental Studies
|
2013
|
tom 22
|
nr 5
This paper investigated concentrations of heavy metals in roadside surface soil samples collected from the D-100 highway in Sakarya, Turkey. The sequential extraction procedure has been applied to 24 soil surface samples and heavy metals concentrations (Ba, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Sr, V, and Zn) determined by ICP-OES. The three-step BCR sequential extraction procedure was used in order to evaluate mobility, availability, and persistence of trace elements in roadside surface soil samples. Validation of the analytical results was checked by analysis of the BCR-701 certified reference material. The results showed good agreement between the obtained and the certified values for the heavy metals analyzed. The results show that Zn (229 µg/g), Pb (227 µg/g), Mn (129 µg/g), Fe (113 µg/g), and Cr (101 µg/g) are the most contaminated heavy metals in roadside surface soil samples.
14

Speciation analysis of lead, zinc and cadmium in river bottom deposits in Swietokrzyskie Region

63%
Rabajczyk A.
Polish Journal of Environmental Studies
|
2008
|
tom 17
|
nr 5
781-789
Bottom deposits of selected rivers in the Świętokrzyskie Region of Poland flowing through areas of various geological characteristics and land development were analyzed for the presence of cadmium, zinc and lead. Microwave-assisted 3-stage sequential extraction recommended by the European Union (EU) was applied for that purpose as well as a 5-stage extraction proposed by Tessier et al. Residues after sequential extraction were mineralized in concentrated nitric acid in order to check if applied sequential extraction procedures allowed extraction of total amounts of metals from bottom deposits. Metal contents were determined with F-AAS technique in particular extracts.
15

Comparison of sequential extraction methods with reference to zinc fractions in contaminated soils

63%
Gworek B., Mocek A.
Polish Journal of Environmental Studies
|
2003
|
tom 12
|
nr 1
The total amount of zinc extracted from soils in the Legnicko–Głogowski Copper Mining Region using either the McLaren and Crawford or Tessier et al. method differed within the limits of 2–35%, while the application of the latter method yielded higher results for 86% of analyzed samples. Amongst zinc fractions analyzed using the McLaren and Crawford method the fraction of zinc specifically bound and less easily exchangeable dominates in horizons where there is an accumulation of organic matter while in the remaining horizons a residual fraction. Whereas when the Tessier et al. method was used the residual fraction dominated in all the genetic horizons of soils under study. The smallest amounts of zinc, regardless of the method applied, were found in the fraction embracing ions found in the soil solution and those easily exchangeable. The quantity of mobile zinc (accessible for plants) calculated on the basis of sequential extraction according to McLaren and Crawford procedure amounts to up to 14–54% while the quantity obtained by the Tessier et al. method amounts to up to 6–28% of total zinc value. A significant difference was found in accumulation horizons and amounted to 40-54% and 8-28% respectively. The share of organic substance in zinc binding was smallest when assessed on the basis of sequential analysis according to McLaren and Crawford. While in the case of applying the method by Tessier et al. the smallest amounts of zinc were bound to carbonates, sulphates and phosphates.
16

Validation and optimization of conditions for the sequential extraction of manganese from ash

63%
Kalembkiewicz J., Sitarz-Palczak E.
Polish Journal of Environmental Studies
|
2005
|
tom 14
|
nr 1
Methods of sequential extraction are used to determine various chemical forms of metals in environmental samples. With the variety of different sequential extraction procedures used in environmental exploration studies, it is difficult to compare results between studies. The attempt of validation of methods of analysis of chemical fraction of Mn in ashes by FAAS method for two procedures of sequential extraction (BCR and Tessier et al.) was perfomed. It was found that both tested procedures give comparable and reproducible results. The optimal conditions of BCR methods were established, which are: parameters of ash sample (grain diameter – 0.06 mm, drying temperature – 110°C for 24 hrs, mass sample – 1.00 g) and parameters of sequential extraction process (time – 6 hrs, relation of mass of sample to the volume of extraction solution – 1:4). The optimum conditions of sequential extraction of Mn from coal fly ash can be applied in the study of chemical fraction of Mn in fly ash in different research laboratories.
17

Investigations of chemical fraction of Cr in soil

63%
Kalembkiewicz J., Soco E.
Polish Journal of Environmental Studies
|
2005
|
tom 14
|
nr 5
The influence of Cr (III) and Cr (VI) on biochemical reactions in the environment depends in part on the possibility of its getting from soil to soil solutions. The various methods of sequential extraction of Cr from soil were studied (Tessier et al. [1, 2], Rudd [3], BCR [4-7], Gatehouse [8], Kersten and Förstner [9], Psenner [10], Sposito [11]) in order to characterize chemical fractions. It was found that chromium determination depends on the method used and varies from 18.2% (BCR) to 96.5% (Tessier) of chromium detection in soil (34.1 mg·kg⁻¹). Quantitative evaluation of chemical fraction of Cr in soil by methods of sequential extraction was carried out by Tessier [1-2], Kersten and Förstner method [9] and indicated that Cr desorption increases according to the following order: exchangeable fraction
18

Changes in zinc combinations in sewage sludge composted with and without an addition of lime

63%
Jakubus M.
Electronic Journal of Polish Agricultural Universities. Series Environmental Development
|
2003
|
tom 06
|
nr 2
The share of zinc in fractions is not constant and changes under the influence of different factors. Taking it into consideration relevant studies were conducted. Their aim was to explain the influence of time factor and addition of calcium oxide into the sewage sludge on the quantitative changes of zinc in particular chemical fractions of sludge. The experiment was carried out in incubation conditions in time of six months.
19

Changes in copper forms while composting municipal solid waste

63%
Ciba J., Zolotajkin M.
Archiwum Ochrony Środowiska
|
1999
|
tom 25
|
nr 2
20
Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik
Content available

Profile differentiation of lead and chromium fractions found in soils localized on a moraine slope

51%
Kalembasa D., Majchrowska-Safaryan A., Pakula K.
Journal of Elementology
|
2009
|
tom 14
|
nr 4
In order to evaluate a potential threat to soil environment by heavy metals, it is important to separate and determine their fractions by means of sequential extraction. The research aimed at evaluating the total content of lead and chromium as well as their fractions in soils localized on a moraine slope in the Siedlce Heights (transects A and B). Sequential fractionation of these elements was carried out according to Zeien and Brümmer’s method. Chemical analyses revealed varied contents of seven lead and chromium fractions in the soils. The largest amounts of both heavy metals were mostly recorded in the residual fraction (F7), and those of lead also in the organic fraction (F4). The least lead was found in the exchangeable fraction (F2) (it was not detected in easily soluble fraction F1), while the least chromium appeared in the easily soluble (F1) and organic fractions (F4). Statistical processing revealed that the examined lead and chromium fractions generally depended on separated fractions, total contents of these metals, and some properties of analyzed soils.
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