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Determination of content of organic compounds in biochar
Novotná, Martina ; Řezáčová, Veronika (referee) ; Mravcová, Ludmila (advisor)
Biochar is created during the pyrolysis of organic biomass. Once added into the soil, it can improve its features. Biochars made from sewage sludge have various compositions. It is because of the vast difference between entrance materials. Organic pollutants can be absorbed into its surface during the cooling proces sof pyrolysis. If released into the enviroment, these compounds can cause inhibition of plant growth, get into food chains and adversely affect living organisms. Organic pollutans are determined most often by GC/MS after organic solvent extraction.
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Analysis of organic substances present in biochar
Bača, Ondřej ; Řezáčová, Veronika (referee) ; Mravcová, Ludmila (advisor)
This master's thesis deals with the analysis of organic substances, which are present in biochar. Biochar contains a number of organic compounds, that can be toxic and also carcinogenic to living organisms. In order for biochar to be used to improve soil quality or to be used for other applications, its safety must be declared by European or international certifications. Relevant European and international standards have been created for the determination of organic substances, that could be present in biochar. The theoretical part of the thesis was focused on selected organic substances, the process of pyrolysis and thermochemolysis, biochar characterisation and the used analytical methods. The experimental part of the thesis consisted of extraction with toluene and after that the determination of concentration of the 38 polycyclic aromatic hydrocarbons was performed. Qualitative analysis was performed by two-dimensional gas chromatography. Biochar samples were also subjected to thermochemolysis method and then they were analysed on GC-MS again. In both analytical methods, a large number of substances from groups such as PAHs, carboxylic acids, amines, substituted naphthalenes etc. was found, as well as smaller number of eg. polychlorinated biphenyls.
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Characterization of organic substances in biochar and their release in the soil ecosystem
Bočán, David ; Doležalová Weissmannová, Helena (referee) ; Mravcová, Ludmila (advisor)
The aim of this master’s thesis was to optimize the extraction of 38 PAH and 7 PCB compounds from samples of commercially available biochar and then apply the most suitable extraction method to real samples of biochar and soil. The concentrations of mentioned compounds were determined by using gas chromatography with mass spectrometry detection. Finally, from these concentrations in individual samples, a rate of release of these compounds from biochar to soil was determined. The theoretical part was focused on summarizing the process of biochar production and its properties. The next part deals with compounds that can be present in biochar, their physicochemical properties and effects on organisms and the environment. Also, a most common ways of extracting and determinating these compounds are mentioned. The final part focuses on soil and its characteristics and the changes it undergoes when biochar is applied to it. In the practical part an extensive optimization of extractions using a PSE extractor and thermal desorption extraction was conducted. After determining optimal conditions for both types of extraction methods, these methods were applied to real samples of biochar and soil. Qualitative analysis was carried out using GCxGC-TOF mass spectrometer and quantitative analysis by MRM method on GC-MS2 mass spectrometer.
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Characterization of organic substances in biochar and their release in the soil ecosystem
Bočán, David ; Doležalová Weissmannová, Helena (referee) ; Mravcová, Ludmila (advisor)
The aim of this master’s thesis was to optimize the extraction of 38 PAH and 7 PCB compounds from samples of commercially available biochar and then apply the most suitable extraction method to real samples of biochar and soil. The concentrations of mentioned compounds were determined by using gas chromatography with mass spectrometry detection. Finally, from these concentrations in individual samples, a rate of release of these compounds from biochar to soil was determined. The theoretical part was focused on summarizing the process of biochar production and its properties. The next part deals with compounds that can be present in biochar, their physicochemical properties and effects on organisms and the environment. Also, a most common ways of extracting and determinating these compounds are mentioned. The final part focuses on soil and its characteristics and the changes it undergoes when biochar is applied to it. In the practical part an extensive optimization of extractions using a PSE extractor and thermal desorption extraction was conducted. After determining optimal conditions for both types of extraction methods, these methods were applied to real samples of biochar and soil. Qualitative analysis was carried out using GCxGC-TOF mass spectrometer and quantitative analysis by MRM method on GC-MS2 mass spectrometer.
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Mechanism of microbial biodegradation of polychlorinated biphenyls
Šrédlová, Kamila ; Cajthaml, Tomáš (advisor) ; Kočí, Vladimír (referee) ; Macek, Tomáš (referee)
Polychlorinated biphenyls (PCBs) are chlorinated organic compounds, which belong to persistent organic pollutants and exhibit various modes of toxic action, including mutagenicity, carcinogenicity, and endocrine disruption. PCBs were manufactured during the 20th century in many countries and extensively used due to their advantageous physicochemical properties. PCBs mostly served as insulating liquids in electrical equipment; however, they were also utilized in many open applications. Despite the worldwide ban on PCB manufacture imposed at the end of the 20th century, the contamination of the environment persists to this day as a result of their recalcitrance. Moreover, PCBs are still being inadvertently produced during many industrial activities. Because of their stability, the breakdown of PCBs in nature is extremely slow. This dissertation thesis focuses on the study of PCB biodegradation by ligninolytic fungi. This group of microorganisms belongs to the most promising, especially in regard to the degradation of organic pollutants. The biodegradation mechanism of PCBs was studied in vitro, including the identification of degradation intermediates. Laccase, an enzyme expressed by the oyster mushroom (strain Pleurotus ostreatus 3004), was able to degrade hydroxylated PCBs. In addition, chlorinated...
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Analysis of organic substances present in biochar
Bača, Ondřej ; Řezáčová, Veronika (referee) ; Mravcová, Ludmila (advisor)
This master's thesis deals with the analysis of organic substances, which are present in biochar. Biochar contains a number of organic compounds, that can be toxic and also carcinogenic to living organisms. In order for biochar to be used to improve soil quality or to be used for other applications, its safety must be declared by European or international certifications. Relevant European and international standards have been created for the determination of organic substances, that could be present in biochar. The theoretical part of the thesis was focused on selected organic substances, the process of pyrolysis and thermochemolysis, biochar characterisation and the used analytical methods. The experimental part of the thesis consisted of extraction with toluene and after that the determination of concentration of the 38 polycyclic aromatic hydrocarbons was performed. Qualitative analysis was performed by two-dimensional gas chromatography. Biochar samples were also subjected to thermochemolysis method and then they were analysed on GC-MS again. In both analytical methods, a large number of substances from groups such as PAHs, carboxylic acids, amines, substituted naphthalenes etc. was found, as well as smaller number of eg. polychlorinated biphenyls.
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Determination of content of organic compounds in biochar
Novotná, Martina ; Řezáčová, Veronika (referee) ; Mravcová, Ludmila (advisor)
Biochar is created during the pyrolysis of organic biomass. Once added into the soil, it can improve its features. Biochars made from sewage sludge have various compositions. It is because of the vast difference between entrance materials. Organic pollutants can be absorbed into its surface during the cooling proces sof pyrolysis. If released into the enviroment, these compounds can cause inhibition of plant growth, get into food chains and adversely affect living organisms. Organic pollutans are determined most often by GC/MS after organic solvent extraction.
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Biodegradation of polychlorinated biphenyls in underground water using biological approaches.
Šrédlová, Kamila ; Cajthaml, Tomáš (advisor) ; Innemanová, Petra (referee)
Polychlorinated biphenyls (PCBs) are a class of important organic pollutants which undergo very slow degradation and tend to persist for a long time in the environment. PCBs have various negative effects on living organisms, human health and the environment in general. A method for determining PCB levels in aqueous matrices was developed consisting of solid-phase extraction (SPE) and GC/MS determination. The average recoveries of PCB congeners from artificially spiked deionized water were around 85%. The PCB concentration of 3.3±0.1 μg·l-1 (a sum of selected congeners) was detected in contaminated groundwater originated from the area of a former asphalt concrete producing plant. The most abundant PCBs were trichlorinated congeners which together comprised about 80% of the total PCB content. The optimised SPE method was further applied together with accelerated solvent extraction (ASE) to assess the degradation potential of oyster mushroom (Pleurotus ostreatus) which shows high degradation efficiency of various organic pollutants including PCBs. P. ostreatus belongs to ligninolytic (white-rot) fungi, which is a very promising group of microorganisms frequently studied due to their bioremediation potential. P. ostreatus, strain KRYOS was able to remove 41±8% of the initial amount (50 μg) of the...
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Combined methods Remediation of groundwater by combination of sodium lactate and zero valent nanoiron
Stejskal, Vojtěch ; Bruthans, Jiří (advisor) ; Černík, Miroslav (referee)
Vojtěch Stejskal - Diplomová práce 2014 - Přírodovědecká fakulta UK v Praze 4 ABSTRACT The thesis describes pilot applications of combined method - combination of sodium lactate and nanoparticles of zero-valent iron and their synergic effect. Two applications of combined method are described onto two geologically different sites - in Rožmitál pod Třemšínem and Spolchemie in Ústí nad Labem. First site is contaminated by polychlorinated biphenyls; contamination is situated in hydraulically well conducted porous media formed by weathered granodiorite. Main contaminants of Spolchemie site are trichloroethylene and tetrachloroethylene, contamination is situated in geologically heterogenous quaternary terrace of Bílina river. Effects of combined method on two different sites were compared and recommendations and conclusions were done. Part of the thesis is research of scientific articles and literature on topics: polychlorinated biphenyls, chlorinated ethylenes, in situ chemical reduction by sodium lactate and nanoiron, natural conditions of both sites, history of sites. In the thesis are also processed and evaluated results of geophysical investigation, changes of groundwater level and results of groundwater monitoring in view of the application of combined method on both sites.
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Bioremediation of persistent aromatic pollutants
Stella, Tatiana ; Cajthaml, Tomáš (advisor) ; Mihaljevič, Martin (referee) ; Tesařová, Eva (referee)
The remediation of persistent chlorinated aromatic compounds has become a priority of great relevance due to the teratogenic, carcinogenic and endocrine-disrupting properties of these xenobiotics. The use of biological methodologies for the clean-up of contaminated sites, collectively referred to as "bioremediation", has been gaining an increasing interest in recent years because it represents an effective, cost-competitive and environmentally friendly alternative to the physico-chemical and thermal treatments. In this respect, "white rot" fungi, an ecological subgroup of filamentous fungi, display features that make them excellent candidates to design an effective remediation technology ("mycoremediation"). In spite of this, fungi have not been widely exploited for their metabolic capabilities and the mechanism by which they are able to degrade the aforementioned pollutants has not been fully elucidated yet. Within this frame, the present Ph.D thesis was aimed at: i) assessing the efficiency of different mycoremediation strategies for the clean-up of a polychlorinated biphenyl (PCBs)-contaminated soil; ii) understanding the fungal degradation pathways of polychlorinated biphenyls and their major metabolites, namely chlorobenzoic acids (CBAs) and hydroxylated polychlorinated biphenyls (OH-PCBs). i)...
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