scholarly journals Sequential extraction and thermal desorption of mercury from contaminated soil and tailings from Mongolia

2012 ◽  
Vol 10 (5) ◽  
pp. 1565-1573 ◽  
Author(s):  
Pavel Coufalík ◽  
Pavel Krásenský ◽  
Marek Dosbaba ◽  
Josef Komárek
Keyword(s):  
Sequential Extraction ◽  
Thermal Desorption ◽  
Solid Phase ◽  
Extraction Procedure ◽  
Speciation Analysis ◽  
Water Soluble ◽  
Mercury Species ◽  
Different Temperatures ◽  
Acidic Conditions ◽  
Desorption Method

AbstractMercury forms in contaminated environmental samples were studied by means of sequential extraction and thermal desorption from the solid phase. The sequential extraction procedure involved the following fractions: water soluble mercury, mercury extracted in acidic conditions, mercury bound to humic substances, elemental Hg and mercury bound to complexes, HgS, and residual mercury. In addition to sequential extraction, the distribution of mercury species as a function of soil particles size was studied. The thermal desorption method is based on the thermal decomposition or desorption of Hg compounds at different temperatures. The following four species were observed: Hg0, HgCl2, HgS and Hg(II) bound to humic acids. The Hg release curves from artificial soils and real samples were obtained and their applicability to the speciation analysis was considered.

scholarly journals Mercury determination and speciation analysis in surface waters

2012 ◽  
Vol 10 (4) ◽  
pp. 1175-1182 ◽  
Author(s):  
Elisaveta Mladenova ◽  
Ivanka Dakova ◽  
Dimiter Tsalev ◽  
Irina Karadjova
Keyword(s):  
Surface Waters ◽  
Inductively Coupled Plasma ◽  
Mechanical Stability ◽  
Solid Phase ◽  
Chemical Vapor ◽  
Speciation Analysis ◽  
Regeneration Ability ◽  
Mercury Species ◽  
Icp Ms ◽  
Relative Standard

AbstractA sorbent L-cysteine grafted silica gel has been evaluated for separation and enrichment of dissolved inorganic i-Hg(II) and methylmercury CH3Hg(I) from surface waters at sub-µg L−1 concentrations. Chemical parameters for mercury species enrichment and separation have been optimized. Analytical schemes for the determination of Hg species, using selective column solid phase extraction (SPE) with continuous flow chemical vapor generation atomic absorption spectrometry (CF-CVG-AAS) or inductively coupled plasma-mass spectrometry (ICP-MS) were developed. Possibilities for on-site SPE enrichment were demonstrated as well. The limits of quantification were 1.5 and 5 ng L−1 for dissolved i-Hg(II) and CH3Hg(I) by CF-CVG-AAS and 1 and 2.5 ng L−1 by ICP-MS with relative standard deviations between 7–12% and 7–14%, respectively. The chemically modified SPE sorbent has demonstrated high regeneration ability, chemical and mechanical stability, acceptable capacity and good enrichment factors. Results for total dissolved mercury were in reasonable agreement with those from independent analyses by direct ICP-MS determinations for river waters and for estuarine water certified reference material.

scholarly journals Application of a Sequential Extraction Method for Analyzing Cu Distribution in Pre-Treated Mine Tailings after Electrodialytic Remediation

2019 ◽  
Vol 16 (4) ◽  
pp. 584 ◽  
Author(s):  
Andrea Lazo ◽  
Henrik Hansen ◽  
Pamela Lazo ◽  
Claudia Gutiérrez
Keyword(s):  
Sequential Extraction ◽  
Mine Tailings ◽  
Extraction Method ◽  
Constant Electric Field ◽  
Extraction Procedure ◽  
Water Soluble ◽  
Copper Compounds ◽  
Leaching Solution ◽  
Sequential Extraction Method ◽  
Pre Treatment

Mine tailings have been analyzed by a sequential extraction procedure after their pre-treatment with a leaching solution for 24 h and electrodialytic remediation during 15 days with a constant electric field of 2.7 V cm−1. Four leaching solutions were tested: H2SO4 + HNO3 (2:1 vol.) pH = 1.9; H2SO4 + HNO3 (2:1 vol) pH = 4.2; NH4Cl 0.8M, pH = 5.5 and 30% H2O2 adjusted to pH 2 with HNO3 1M + HCl 1M. After the treatment, the tailings were divided in six slices from anode to cathode. The highest removal efficiency of copper was obtained with H2SO4 + HNO3 pH = 1.9, which allows one to remove 67% of the copper in the total cell and 85% of the copper in the slice closest to anode. The same solution with pH = 4.2 allows one to remove 62% of the total copper. The analysis realized by the sequential extraction method indicates the easy removal of water-soluble and exchangeable fractions in all experiments, moreover, residual and sulfide are the less mobile fractions. The general trend was the movement of copper associated to different fractions from anode to cathode and its accumulation closest to the cathode in the case of exchangeable, Fe-Mn oxides and acid soluble fractions, possibly due to some precipitation of copper compounds associated with less acidic conditions.

EVALUATION OF LEACHING AND BIOAVAILABILITY OF HEAVY METALS FROM INDUSTRIAL BIOMASS ASHES

2017 ◽  
Vol 167 (47) ◽  
pp. 18-33
Author(s):  
Justyna Koniuszy-Nycz
Keyword(s):  
Sequential Extraction ◽  
Ph Effect ◽  
Microwave Digestion ◽  
Extraction Procedure ◽  
Total Content ◽  
Water Soluble ◽  
Test Material ◽  
Biomass Combustion ◽  
Solution Ph ◽  
Biomass Ashes

The purpose of the study was to evaluate the total content, leachability and bioavailability of Fe, Zn, Cu, Cr, Cd, Pb, Ni, Co in industrial ashes obtained from biomass combustion. It was found that metals occur in the test material as: macronutrient - iron (0,67 %), micronutrients - zinc (335,0 mg/kg), nickel (145,0 mg/kg), lead (110,0 mg/kg), copper (100,0 mg/kg), cobalt (25,0 mg/kg), chrome (15 mg/kg) and trace amount of cadmium (10,0 mg/kg). It was claimed that leachability of metals from ash depends on pH of solution and ranges from 1 mg/kg for (Cu, Cd, Ni, Fe) to 4 – 5 mg/kg for (Cr, Co) respectively. It was also found that lead was not extracted from ash, using water as extractant regardless of solution pH. In all experiments no regularities in the pH effect of metal leachability in the investigated systems were observed. Tessier sequential extraction procedure was used to evaluate the mobility and bioavailability of metals, which was carried out conventionally and with aid of microwave digestion. In all experiments the following metal fractions were characterized: water-soluble, exchangeable, acid-soluble, oxide, pseudosulfide and residual fractions respectively. It has been found that the use of microwave mineralization during sequential extraction increases the efficiency of the release of most of the tested metals.

scholarly journals Improvement of the sequential extraction procedure based on supercritical CO2 and subcritical H2O solvents for the estimation of the environmentally mobile potentially toxic element fractions of sediments and soils

2018 ◽  
Vol 67 (1) ◽  
pp. 35-48
Author(s):  
Anita Takács ◽  
Katalin Kovács ◽  
Gábor Halász ◽  
Zoltán Győri ◽  
Ilona Fekete ◽  
...  
Keyword(s):  
Sequential Extraction ◽  
Extraction Procedure ◽  
Potentially Toxic Elements ◽  
Toxic Element ◽  
Water Soluble ◽  
Sequential Extraction Procedure ◽  
Mass Ratio ◽  
Fractionation Procedure ◽  
Soils And Sediments ◽  
Element Contents

The estimation of environmental risk caused by pollution with potentially toxic elements (PTE) is usually carried out using the (3+1) step sequential extraction procedure suggested in 1993 by the Community Bureau of Reference (BCR). In the 1st step the water-soluble, exchangeable and carbonate-bound element content is extracted with acetic acid. In 2002 a fractionation procedure based on the application of supercritical CO2, subcritical H2O and of a mixture of subcritical H2O/CO2 was proposed, which allowed the water-soluble and carbonatebound element contents to be extracted separately from sediment or soil samples weighed into the preparative column of a supercritical fluid extractor and diluted with quartz sand in a mass ratio of 1:20. The aim of the present study was to develop a new reduced-size column construction with which this dilution rate could be decreased to 1:2. A kinetic study was performed to determine the extraction time necessary for samples with different carbonate contents and the extracted element contents were compared to the results of the BCR sequential procedure on the same samples. It was established that fractionation using the reduced-size column may be a rapid way to obtain more reliable information on the easily mobilizable (watersoluble and carbonate-bound) PTE content of soils and sediments than was previously available to supplement BCR fractionation.

scholarly journals Speciation Analysis for Heavy Metals in Sediments at Kusaki Dam-Lake with Sequential Extraction Procedure

2010 ◽  
Vol 59 (9) ◽  
pp. 829-837 ◽  
Author(s):  
Koji Nakano ◽  
Masahiro Sato ◽  
Ayako Tsuda ◽  
Haruka Sekiya ◽  
Masanobu Mori ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Sequential Extraction ◽  
Extraction Procedure ◽  
Speciation Analysis ◽  
Sequential Extraction Procedure

scholarly journals Assessment of mercury pollution sources in beach sand and coastal soil by speciation analysis

2019 ◽  
Vol 31 (1) ◽  
Author(s):  
José Luis R. Gallego ◽  
Maria Antonia López-Antón ◽  
Deva Martínez de la Rosa ◽  
Eduardo Rodríguez-Valdés ◽  
Nerea García-González ◽  
...  
Keyword(s):  
Thermal Desorption ◽  
Inorganic Mercury ◽  
Coastal Region ◽  
Speciation Analysis ◽  
Beach Sand ◽  
Mercury Species ◽  
Mercury Oxide ◽  
Icp Ms ◽  
Soils And Sediments ◽  
Beach Sands

Abstract Background An essential requisite for controlling and monitoring mercury in the environment is to identify its species in different types of soils and sediments, as this will help not only to establish its mobility in the environment and ecosystem and the degree of its toxicity, but also to establish the source of contamination. The objective of this work was to identify the origin of mercury in beach sands and soil taken from a coastal region with previously high mining and industrial activity by characterizing the mercury species using the technique known as thermal desorption (HgTPD). Results Apart from quartz, the main mineral species identified in the raw sands and soil were calcite, fluorite and barite. The concentration of mercury ranges from 5 to 23 µg g−1, and although it is distributed in different proportions in the function of the size, thermal desorption profiles demonstrated that the mercury species present in the samples do not vary with the mercury concentration and the particle size. By means of HgTPD, mercury oxide (HgO) was identified in the beach sands, whereas mercury sulfide (HgS) was found in the soil sample taken from the vicinity of the beach. Complementary methodologies foster the HgTPD conclusions and verify that mercury is present mostly in insoluble stable (HgS) or low-mobility (HgO) forms in the samples studied. Analyses by ICP-MS after sequential extraction and HPLC separation of mercury species show that inorganic mercury is the predominant form in the samples. Conclusions The technique HgTPD is a very useful tool to ascertain the origin of mercury in contaminated beach sands and shoreline soils. In the particular area studied in this work, the species identified indicate that previous mining activity was the source of the mercury and rule out the possibility that contamination is derived from coal combustion activities ongoing in the region.

Rapid Analysis of Animal Drug Residues by Microcolumn Solid-Phase Extraction and Thermal Desorption–Ion TYap Mass Spectrometry

1994 ◽  
Vol 77 (6) ◽  
pp. 1428-1434 ◽  
Author(s):  
Stacy-Ann Barshick ◽  
Michelle V Buchanan
Keyword(s):  
Mass Spectrometry ◽  
Thermal Desorption ◽  
Chemical Ionization ◽  
Ion Trap ◽  
Solid Phase ◽  
Extraction Procedure ◽  
New Approach ◽  
Ion Trap Mass Spectrometer ◽  
Simple Extraction

Abstract A new approach was developed for the rapid and quantitative determination of an anthelmintic drug, phenothiazine, in milk. The technique involves a simple extraction procedure using a C18 microcolumn disc, followed by thermal desorption of the analyte from the disc directly into an ion trap mass spectrometer. The compounds are selectively ionized by isobutane chemical ionization and detected by tandem mass spectrometry. With this approach, 10 ppb detection limits were achieved with as little as 100 μL milk and only 10 min of analysis time. This approach was used to analyze samples of milk taken from a cow administered a one-time therapeutic dose of phenothiazine. The target compound could be detected at 56 h post-dosage, corresponding to a concentration of 30 ppb.

Research on Influences of "A Test of Different Initial pH from the Reaction" with Properties of Environment Materials on Distribution of Arsenic Speciation Arsenic-Ferric Precipitation

2014 ◽  
Vol 1014 ◽  
pp. 307-310
Author(s):  
Xing Guan Ma ◽  
Meng Qi Wang
Keyword(s):  
Sequential Extraction ◽  
Ferric Chloride ◽  
Arsenic Removal ◽  
Arsenic Speciation ◽  
Extraction Procedure ◽  
Water Soluble ◽  
Specific Adsorption ◽  
Physical Absorption ◽  
Initial Ph ◽  
Soluble State

The distribution of arsenic speciation can be applied to elucidate the mechanism of removal arsenic during treatment the water containing arsenic with molysite. In this study, the effect of initial pH on the distribution of arsenic speciation in arsenic-ferric precipitation was determined by a five-step sequential extraction procedure. And then further explore the mechanism of arsenic removal with molysite. This experimental results showed that the main mechanisms governing the arsenic removal with ferric chloride were specific adsorption and coprecipitation. Besides, as pH increased from 5 to 9, the arsenic-ferric coprecipitation played a more and more important role in mechanism of arsenic removal with molysite. At the same time, the water soluble state As and the non-specific adsorption As were barely detectable, which suggested that physical absorption had almost no effect on arsenic removal.

Sign in / Sign up

Export Citation Format

Share Document