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Study of adsorption of organic pollutants on wheat bran biochar
Hanák, Jan ; Pořízka, Jaromír (referee) ; Diviš, Pavel (advisor)
This diploma thesis explores the application of the Diffusive Gradients in Thin Films (DGT) method for determining and monitoring the concentrations of dissolved pharmaceuticals and organic dyes in water and food. The theoretical part introduces the issue of the occurrence of these organic substances in water and food, the principles of the DGT method, the characteristics of adsorption and adsorption isotherms, and the introduction of biochar as an adsorbent. The experimental section primarily focuses on optimizing and validating adsorption gels containing commercial biochar and unmodified biochar from wheat bran for the adsorption of specific substances using the DGT method. Oxytetracycline was primarily tested from a selection of antibiotics and malachite green from organic dyes, which is widely used in aquaristics. The results demonstrate a comparison of the effectiveness of adsorption using these two types of adsorbents and their characteristics, such as infrared spectroscopy analysis or images from a scanning electron microscope. From the Langmuir isotherm, the maximum adsorption capacity for oxytetracycline on commercial biochar was found to be 314,065 mgg-1 and the maximum adsorption capacity for wheat bran biochar was 89,720 mgg-1. The maximum adsorption capacity of commercial biochar for malachite green was 439,406 mgg-1. The work further emphasizes the potential of the DGT method as a tool for food analysis and investigating contaminants in water systems, which further move into the food chain.
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Study of the interaction of hazardous metal – microplastic
Sinčáková, Lenka ; Řezáčová, Veronika (referee) ; Doležalová Weissmannová, Helena (advisor)
Mikroplasty, široko zastúpené vo vodnom prostredí, slúžia ako vektor širokej škály kontaminantov, vrátane ťažkých kovov. Táto práca sa zaoberá adsorpciou piatich ťažkých kovov (Pb, Hg, Zn, Cu and Cd) na polyetylén tereftalát (PET), rozšírený polutant riek a morí. Pokiaľ ide o vplyv veľkosti mikroplastov na proces adsorpcie, nebol zistený jasný trend. Salinita prostredia má značný vplyv na adsorpčný proces s pozorovateľným poklesom adsorbovaných množstiev v prostredí s vysokou iónovou silou. Analyzované ťažké kovy boli zoradené vzostupne podľa ich schopnosti adsorpcie na PET nasledovne: Hg
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Sorption ability of humic acids
Pokorná, Markéta ; Havelcová, Martina (referee) ; Klučáková, Martina (advisor)
The Diploma thesis deals with humic acids and their ability to adsorb metal ions on their surface. Humic acids are aromatic polycyclic compounds which contain carboxylic and fenolic functional groups on their sidechains. Thanks to these functional groups humic acids can form complexes with metal ions of different stability and assist the partial immobilization of pollutants in the nature. In this thesis, the sorption of Pb2+ and Zn2+ ions on humic acids was studied by relatively new electroanalytic method called galvanostatic stripping chronopotentiometry. Experimental data were described by Freundlich and Langmuir isotherms. The results show that the amount of examined metal ions increases with their increasing concentration. Furthermore it was determined that Pb2+ ions are adsorbed better on humic acids than Zn2+ ions. Both metals are adsorbed better from solution containing only one metal ion than in presence of four metals at the same time (Cd, Cu, Zn and Pb) where the sorption of these metals is not influenced by the presence of other metals.
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Application of activated carbon in flue gas treatment process
Navrátil, Petr ; Niesner, Jakub (referee) ; Jedlička, Filip (advisor)
The objective of this bachelor thesis is to explain the problematic of flue gas treatment from the air pollutants mainly by methods using adsorption on activated carbon. There is an introduction to environmental protection, description of selected chemicals, charcoal and description of technologies to remove pollutants in municipal waste incinerators, and finally mention the possibilities of disposal or reuse of a saturated carbon. And finally selection of appropriate methods and design for a specific application.
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Detection of biochemical substance using graphene sensor
Supalová, Linda ; Šimšíková, Michaela (referee) ; Bartošík, Miroslav (advisor)
Tato bakalářská práce studuje interakci biochemických látek s grafénem pomocí senzorů v uspořádání polem řízeného tranzistoru. Adsorbované atomy nebo molekuly mohou vyvolat dopování grafénové vrstvy, což může být experimentálně určeno pozorováním změny pozice Diracova bodu. Je studována závislost polohy Diracova bodu na přidané látce a stejně tak i časová odezva na přidání kapalného vzorku. Je pozorována citlivost na odlišné molekuly a jsou dikutovány důsledky výsledků pro adsorpci různých molekul.
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Upgrading biogas by PSA
Krhut, Štěpán ; Havlásek, Martin (referee) ; Zejda, Vojtěch (advisor)
This work deals with bio gas cleaning by a PSA method and modernizing of a laboratory unit. Raw bio gas contains many unwanted elements like carbon dioxide mostly which lowers its energy potential then. To extend the possibilities of usage of bio gas it is necessary to remove such elements. One of the well-known method for eliminating CO2 out of the bio gas is the method called Pressure Swing Adsorption (PSA). This work describes PSA method and compares it with other methods for cleaning the bio gas. In the following part of my work I am introducing the original laboratory PSA unit which is placed in the laboratory of UPI institution for research purposes. The modernization of the method was made by changing the manual valves for electromagnetic ones and there was also designed a new control system unit for two control modes. For manual and for automatic. The essential function is based on remote controlling the valves either by switches or by a program. The electric control panel was created for such required modes. The automated process was controlled by Arduino programming platform which was integrated into the panel. In the case of the next measurement and reading there was created a detailed description for user on how to operate the control panel and also the comments for control program of automatization.
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Effect of sub-micrometer structural features on rheology of polymer nanocomposites
Lepcio, Petr ; Chodák,, Ivan (referee) ; doc.Ing.Marián Lehocký, Ph.D. (referee) ; Jančář, Josef (advisor)
Polymerní nanokompozity (PNCs) mají slibnou budoucnost jako lehké funkční materiály zpracovatelné aditivními výrobními technologiemi. Jejich rychlému rozšíření však brání silná závislost jejich užitných vlastností na prostorovém uspořádání nanočástic (NP). Schopnost řídit disperzi nanočástic je tak klíčovým předpokladem pro jejich uplatnění ve funkčních kompozitech. Tato práce zkoumá přípravu polymerních nanokompozitů v modelové sklotvorné polymerní matrici roztokovou metodou, technikou schopnou vytvářet prostorové uspořádání nanočástic řízené strukturními a kinetickými parametry přípravného procesu. Prezentované výsledky popisují rozdíly mezi změnami rheologického chování roztoku polystyrenu při oscilačním smyku s vysokou amplitudou (LAOS) vyvolanými nanočásticemi. Výsledky vedou k závěru, že vysoce-afinní OP-POSS nanočástice při nízkých koncentracích dobře interagují s PS a tvoří tuhé agregáty, zatímco nízko-afinní OM-POSS nanočástice za těchto podmínek neovlivňují deformační chování polymerních řetězců. Dále byla pozornost zaměřena na vliv použitého rozpouštědla na uspořádání nanočástic v SiO2/PMMA a SiO2/PS nanokompozitech, který je v literatuře prezentován jako parametr řídící prostorové uspořádání nanočástic v pevném stavu. Důraz byl kladen na kvalitativní rozdíly mezi „špatně dispergovanými“ shluky nanočástic, které byly na základě rheologie a strukturální analýzy (TEM, USAXS) identifikovány jako polymerními řetězci vázané nanočásticové klastry a dva typy agregátů, jeden termodynamického a druhý kinetického původu. Jednotlivé druhy agregátů se vyznačují odlišnými kinetikami vzniku a rozdílnými vlastnostmi jak mezi sebou, tak v porovnání s dispergovanými nanočásticemi. Pozorované typy disperze nanočástic byly kvantitativně posouzeny podle svých rheologických vlastností během roztokové přípravy, podle kterých byla vyhodnocena míra adsorpce polymeru na povrch nanočástic a atrakce ve vypuzeném objemu. Výsledky byly porovnány s teorií PRISM. Důležitost uspořádání nanočástic byla demonstrována na porovnání teplot skelných přechodů různých struktur při stejném chemickém složení.
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Monitoring the effectiveness of selected adsorbents in removing AOX from water
Rutarová, Natálie ; Kotzurová, Iveta (referee) ; Repková, Martina (advisor)
The diploma thesis was created in cooperation with the company Art Carbon and is focused on monitoring the effectiveness of ART SAND adsorbents in removing AOX from water. The theoretical part provides an overview and basic characteristics of AOX, their impact on the environment and the possibility of their removal. The experimental part is focused on the study of the effectiveness of selected adsorbents with the subsequent use of high performance liquid chromatography (HPLC) with UV detection. Two ART SAND, ASSP50 and ASPP50-X adsorbents, supplied by ArtCarbon, were selected 2,4-dichlorophenol and 2,6-dichlorophenol to monitor adsorption.
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Study of the behavior of insulating materials in a high humidity environment
Havelka, Jindřich ; Peterková, Jitka (referee) ; Zach, Jiří (advisor)
Extruded polystyrene (XPS) is presented as non-absorbent material and it is applied in building construction with high moisture, such as inverted roof. The reason for that is a very good ratio of thermal and mechanical properties and it is used in moisture-loaded applications due to the closed pore structure and high diffusion resistance factor, which are declared by the manufacturers. Long-term experience and studies show that XPS accumulates moisture during long-term exposure in an environment with high humidity. A long-term water absorption test at full immersion for 84 days has been proposed to better illustrate the trend of increasing water absorption. A total of 6 products from different manufacturers that are recommended for inverted roof application, were tested. All tested XPS products have reached high amount of water absorption. The main goal was to map the real properties of XPS at high humidity loads. It was found that each product showed a different degradation of thermal conductivity at the same volume moisture value. Furthermore, there was found the connection between the surface structure and amount of water absorption. Products with waffle structure had higher humidity than products with a fine structure.
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Problems of phenols in water
Tylichová, Petra ; Čáslavský, Josef (referee) ; Doležalová Weissmannová, Helena (advisor)
This bachelor`s thesis deals with the issue of phenols in the waters. The theoretical part summarises the information about the characteristics of the phenols, its use, appearance in the environment, and its effects on human health. There are described methods of determination these substance in the waters. The last chapter disserts on possible methods of eliminating the phenols from the aqueous environment with special attention paid to the adsorption method. Part of this thesis is also dedicated to the chlorinated phenols which originate from chlorination of the phenolic waters and which cause the sensory interferences of the waters. The experimental part of this thesis is dedicated to removing the phenol from a model water through the adsorption into a powdery active carbon Norit SA SUPER.
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