|
|
Advanced remediation technologies for recalcitrant pollutants
Lhotský, Ondřej ; Cajthaml, Tomáš (advisor) ; Šváb, Marek (referee) ; Chrastný, Vladislav (referee)
Advanced remediation technologies for recalcitrant pollutants Studium pokročilých sanačních technologií pro rekalcitrantní polutanty Dissertation thesis Ing. Ondřej Lhotský Abstract This study focuses primarily on the testing and optimization of methods based on modifications to, and the targeted enhancement of, natural microbial processes for the removal of recalcitrant pollutants. Pilot tests were conducted of these innovative methods at real contaminated sites and matrices, and their effectiveness was monitored in the relevant environments. The pilot tests generally confirmed the potential of the modifications and bioremediation technology combinations by revealing significant increases in the removal efficiency for a number of recalcitrant contaminants. The study provides a general summary of the issue of soil and rock environment contamination by recalcitrant contaminants and familiarizes the reader with bioremediation technologies and their optimization for the removal of recalcitrant contaminants. Subsequently, a theoretical introduction is provided of the methods applied in 4 pilot tests of optimized and combined remediation methods at real contaminated sites in the Czech Republic. The pilot tests are described in detail in publications 1, 2, 4 and 5. Publication 6 covers a pilot test conducted on...
|
|
| |
|
|
Speciation and isotopic composition of lead in coal samples from selected profile of the Most Basin
Semíková, Hana ; Strnad, Ladislav (advisor) ; Chrastný, Vladislav (referee)
Coal is one of the major energy sources in the world and contains most of the elements from the periodic table. During combustion of coal these elements are released and redistributed. This may lead to environmental problems. Some of these elements are considered to be very dangerous for human and animal health and ecosystems. The knowledge of concentration and speciation of elements in coal is important for the prevention of the adverse environmental phenomena associated with the use of coal. One of the hazardous elements in coal is lead. The purpose of this work is to determine the concentration of lead and its isotopic composition simultaneously with determining the speciation of lead in coal. The ICP-MS method was used to determine the concentration and isotope ratios of lead. A total of 62 samples of subbituminous coal was analyzed. The method of selective extraction analysis BCR was used on 9 samples of subbitumnious coal to identify the speciation of lead in coal. Lead concentrations in coal were measured in the range of 0.25 to 78.84 mg·kg-1 . These concentrations correspond to the average concentrations of lead in most of the coals. Isotope ratio 206 Pb/207 Pb in coal samples ranged from 1.169 to 1.219. Isotopic 208 Pb/206 Pb ratio was measured in the interval 2.047 to 2.093. The isotopic...
|
|
|
Mercury binding on soil components
Janko, Jiří ; Navrátil, Tomáš (advisor) ; Chrastný, Vladislav (referee)
In this work, a new approach to mercury speciation study on solid samples was tested and verified. This approach is different from commonly applied sequential extraction techniques. Mercury speciation was expressed as a stability constant K, describing the bonding equilibrium between mercury and solid. Stability constant K was measured on soil sample from Příbram, which was characterised in detail (chemical analysis, powder XRD diffraction, thermo desorption analyses). Using solution of potassium resp. ammonium bromide, iodide and thiocyanate the K value was quantified in a wide concentration range. We showed that in mercury in studied sample was present in a single specie with pK 36. We discussed the effect of extractant concentration and experimental setting on resulting K. The result of extraction experiments was in accordance with thermo desorption results confirming mercury present as one specie bound onto clay matrices. As a profound difference in approach to common speciation extraction techniques, in which a set of operationally defined mercury fractions is obtained, the K value obtained in this work represents a thermodynamical parameter feasible for further mathematical processing. Thiocyanate was identified as a useful anion for extraction studies of mercury speciation on solid...
|
|
| |
|
|
Mercury binding on soil components
Janko, Jiří ; Navrátil, Tomáš (advisor) ; Chrastný, Vladislav (referee)
In this work, a new approach to mercury speciation study on solid samples was tested and verified. This approach is different from commonly applied sequential extraction techniques. Mercury speciation was expressed as a stability constant K, describing the bonding equilibrium between mercury and solid. Stability constant K was measured on soil sample from Příbram, which was characterised in detail (chemical analysis, powder XRD diffraction, thermo desorption analyses). Using solution of potassium resp. ammonium bromide, iodide and thiocyanate the K value was quantified in a wide concentration range. We showed that in mercury in studied sample was present in a single specie with pK 36. We discussed the effect of extractant concentration and experimental setting on resulting K. The result of extraction experiments was in accordance with thermo desorption results confirming mercury present as one specie bound onto clay matrices. As a profound difference in approach to common speciation extraction techniques, in which a set of operationally defined mercury fractions is obtained, the K value obtained in this work represents a thermodynamical parameter feasible for further mathematical processing. Thiocyanate was identified as a useful anion for extraction studies of mercury speciation on solid...
|
|
|
Methodology for separation and isotope analysis of magnesium in selected geomaterials
Francová, Michaela ; Farkaš, Juraj (advisor) ; Chrastný, Vladislav (referee)
An efficient methodology for separation of magnesium from different geomaterials was developed in order to determinate their isotopic composition. This methodology with 100% yield is suitable for high precision analysis of Mg isotopes by multi collector inductively coupled plasma mass spectrometry (MC-ICP-MS). Three separate stages of ion-exchange chromatography were carried out in ultra-trace laboratory equipped with laminar flowbox using cation exchange resin, AG50W-X12 and chemicals of ultrapure quality. Variations in samples 26 Mg/24 Mg and 25 Mg/24 Mg ratios are expressed as δ26 Mg and δ25 Mg units, which are deviations in parts per 103 from the same ratio in DSM3 Mg standard. The robustness of the technique was assessed by replicate analyses of magnesium standards Cambridge 1 versus DSM3. The long term repeatability of the Mg isotope ratio measurements of Cambridge 1 against DSM3 using this technique is -2.577 ± 0.10‰ on δ26 Mg and -1.328 ± 0.06‰ on δ25 Mg at 95% of confidence (2σ). Delta 26 Mg in five natural standard samples was measured in order to validate a quality of measurement in two different laboratories: Czech Geological Survey, Prague, Czech Republic and GFS Potsdam, Research centre for geoscientist, Potsdam, Germany. The results measured in this study (laboratory of CGS) are...
|
|
|
The difference in the content of Ca and Mg of moss Hypnum cupressiforme on two types of rock, serpentinite and granulite
Paštyka, David ; Kocourková, Jana (advisor) ; Chrastný, Vladislav (referee)
Most of plants are negatively affected by specific characteristics of serpentine. It is mainly due to the low ratio of Ca: Mg, drought and high content of heavy metals. Specific vegetation occurs on the serpentine thanks to these characteristics. Although many scientists looked into the topic of serpentine, mosses were not focused that much. This research is dedicated to the difference in the content of moss Hypnum cupressiforme on serpentine and granulite in south Bohemia.
This theses found out that bryophytes of serpentine contained significantly higher amounts of magnesium. Ca: Mg ratio was lower in plants at serpentine sites than at control sites. Calcium has been accumulated by mosses on the serpentine and granulite almost equally, on serpentine, magnesium was accumulated 13 times less and nickel 7 times less. Serpentine plants contained significantly higher amounts of nickel and chromium than granulite.
More accurate conclusions would probably bring chemical analyzes of individual parts of bryophytes and analysis of its subsoil. It would be interesting to include pleurocarp and acrocarp mosses and liverworts.
|
|
|
Biogeochemical cycle of rare earth elements in the Lesní potok catchment
Dubroková, Jitka ; Mihaljevič, Martin (advisor) ; Strnad, Ladislav (referee) ; Chrastný, Vladislav (referee)
110 Summary The study of biogeochemical cycle of rare earth elements (REE) carried out in the Lesní potok catchment and its vicinity (located in the Nature State Reserve, Voděradské bučiny, 30 km SE of Prague) was focused on the monitoring of REE concentrations and distribution patterns in natural environment, their relationship with other analysed elements and compounds such as Al, Ca, Fe, K, Mg, Mn, Na, P, S, Si, F- , Cl- , NO3 - SO4 2- , HCO3 - and organic carbon, and its response to physicochemical conditions in various investigated ecosystem compartments. The samples of soil, stream sediment, stream and ground water, rainwater and throughfall in beech and spruce forest, samples of tree assimilatory organs, bark and stem wood of Norway spruce (Picea abies) and European beech (Fagus sylvatica) and lichens (Hypogymnia physodes) were collected in the catchment and its vicinity. Liquid samples were acidified with dilute nitric acid to prevent losses by adsorption, and filtered using a 0.45 µm membrane filter. Stream water samples sampled in months characterized by low and high discharge were processed by ion exchange chromatography and membrane dialyses. Solid samples were dried to constant weight (and sieved and homogenized in case of soil stream sediment samples) and decomposed in the microwave oven with...
|
|
|
Speciation and isotopic composition of lead in coal samples from selected profile of the Most Basin
Semíková, Hana ; Chrastný, Vladislav (referee) ; Strnad, Ladislav (advisor)
Coal is one of the major energy sources in the world and contains most of the elements from the periodic table. During combustion of coal these elements are released and redistributed. This may lead to environmental problems. Some of these elements are considered to be very dangerous for human and animal health and ecosystems. The knowledge of concentration and speciation of elements in coal is important for the prevention of the adverse environmental phenomena associated with the use of coal. One of the hazardous elements in coal is lead. The purpose of this work is to determine the concentration of lead and its isotopic composition simultaneously with determining the speciation of lead in coal. The ICP-MS method was used to determine the concentration and isotope ratios of lead. A total of 62 samples of subbituminous coal was analyzed. The method of selective extraction analysis BCR was used on 9 samples of subbitumnious coal to identify the speciation of lead in coal. Lead concentrations in coal were measured in the range of 0.25 to 78.84 mg·kg-1 . These concentrations correspond to the average concentrations of lead in most of the coals. Isotope ratio 206 Pb/207 Pb in coal samples ranged from 1.169 to 1.219. Isotopic 208 Pb/206 Pb ratio was measured in the interval 2.047 to 2.093. The isotopic...
|
guest ::
RSS feed.