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Qualitative and quantitative analysis of clay soils
Šašek, Petr ; Viani, Alberto ; Mácová, Petra
Smectite-to-illite conversion is an important mineralogical reaction that occurs during the diagenesis ofargillaceous sediment. Illite–smectite clay minerals are ubiquitous in sedimentary basins and they have been linked to the maturation, migration and trapping of hydrocarbons, rock cementation, evolution of porewater chemistry during diagenesis and the development of pore pressure. But, despite the importance of these clays, their structures are controversial. By combining layers of octahedra and tetrahedra several types of layered structures may be produced, which can form various types of clay minerals in nature. Clay minerals are divided into three main groups: kaolinite, smectite and illite. The aim of the study was to qualitatively and quantitatively analyse the clay minerals in soil samples and identification of unknown mineral found by exploration works. For this purpose XRD, Raman spectroscopy and SEM were employed.
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Kinetics of Heterogeneous Processes in Silicate Technologies -Dehydroxylation and Disolution of Clay Minerals
Křečková, Magdaléna ; Kutzendörfer, Jaroslav (referee) ; Kuřitka, Ivo (referee) ; Havlica, Jaromír (advisor)
The first part of the thesis discuss general characterization of heterogeneous processes in silicates. This part is focused on kinetics of heterogeneous processes and mathematical description of reactions time behavior. The other part describes important technologies in silicate industry such as sintering, solid matter decomposition, transition modification, etc. Another chapter deals mineralogy, structure and properties of eminent silicate raw materials. Emphases is given to characterization of clay minerals and their utilising. The experimental part handle the analytic techniques used for investigation of thermal decompostion, dehydroxylation, crystalization of Al-Si spinel phase and sintering process of washed kaolin Sedlec Ia from the region Carlsbad (Czech Republic). Concluding chapter reports on results of experimental work.
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The optimalization of clay building components
Melichar, Jindřich ; Šiler, Pavel (referee) ; Opravil, Tomáš (advisor)
Clay building components are nowadays one of the most used building materials in the world. Except easy availability and processability clay building components have also heat storage function. This master´s thesis will be considering possibilities of improving thermal and mechanic properties of these materils by additing suitable reinforcements.
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Possibilities of clay plasters shrinkage elimination
Melichar, Jindřich ; Koplík, Jan (referee) ; Opravil, Tomáš (advisor)
Earth plasters which are applicated in interiers don´t have just an estetic, but mainly heat storage function. To accomplish better storage properties the plaster has to be laid on the wall in sufficient thick ply. But this use to be accompained by creating of cracks during dehydration of the plaster. This bachelor work will be considering possibilities of elliminating this negative event by additing suitable components to suppress shrinkage and cracks by creating ettringite.
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The problems of fenol sorption from waste water
Židek, Michal ; Pavlovský,, Jiří (referee) ; Doležalová Weissmannová, Helena (advisor)
The bachelor work deals of sorption of phenol from waste water. In theoretical part the basic characteristic of phenol, their effects and presence in environmental compounds are described. The possibility of removal phenol from waste water in waste water treatment is also described. The adsorption process of removal phenol introduced too. The analysis current adsorbents using in removal phenol from aqueous solutions and characteristic properties are also presented in relation to materials on the base of clay minerals. The experimental part is focused on the possibility of removal phenol from aqueous solution via adsorption mechanism under various pH conditions.
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Clay minerals in polymeric materials
Zaťko, Petr ; Sluková, Michaela (referee) ; Krmíček, Lukáš (advisor)
The bachelor thesis deals with the clay minerals as fillers in polymer materials and their polymer/clay nanocomposites. The thesis brings an introduction to the structure of polymers and clay minerals and their application in polymer materials. The practical part of the thesis deals with testing the diffusivity of CO2 through the film made of recycled polyvinyl butyral with fillers Nanofil®5, Dellite® 67 and Cloisite® 93A and their comparison with reference samples from recycled PVB without added fillers and commercial films of extruded PVB.
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Qualitative and quantitative analysis of clay soils
Šašek, Petr ; Viani, Alberto ; Ševčík, Radek ; Fabeš, Roman ; Řehoř, M.
Clay minerals are a group of aluminum silicates with a layered structure, which is formed by tetrahedrally and octahedrally arranged molecules with cations of potassium, magnesium, sodium and others. By combining layers of octahedra and tetrahedra several types of layered structures may be produced, which can form various types of clay minerals in nature. Clay minerals are divided into three main groups: kaolinite, smectite and illite. The aim of the study was to qualitatively and quantitatively analyse the clay minerals in soil samples; the main objective was to determine the phase transition on the boundary of smectite and illite phases. For this purpose XRD analysis with Rietveld refinement was employed.
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Thermal behaviour of organically modified clays
Plevová, Eva ; Vaculíková, Lenka ; Vítámvásová, E. ; Šugárková, Věra ; Martynková, G.S.
The clay minerals were modified by two alkylammonium cations under sorption procedure. T X-ray powder diffraction and FT-IR spectroscopy were used to evaluate the intercalation process of organic cations int the clay structure. The organo - montmorillonites exhibited IR spectra giving evidence about sorption or intercalation of the alkylammonium cations. The enhancement of the basal spacing obtained by X-ray diffraction confirmed the intercalation process of cations into montmorillonite and vermiculite samples. Thermal behaviour of the modified clay minerals was investigated by simultaneous thermogravimetry and differential thermal analysis. The organically modified montmorillonites exhibited the higher values of temperatures related to the total melting. Also the temperatures of exotherm effects connected to recrystallization and transformation increased with the concentration of alkylammonium salts. The temperatures of dehydratation and dehydroxilation decreased with concentration of alkylammonium cations. Vermilulite samples showed generally reducing of their thermal stability.
Fulltext: content.csg -  PDF
Plný tet: UGN-0393204 - PDF
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Limitations of spectroscopic methods in the study of earthy pigments
Košařová, V. ; Hradil, David ; Kanický, V.
Nowadays, the spectroscopic methods, above all Infrared Spectroscopy (IR), are the most frequently used analytical methods in the research of cultural heritage, which is mainly caused by easy use and non-invasiveness of these methods and a broad range of their application, which comprises both organic and inorganic substances. Nevertheless, each analytical technique has its detection limits, and the fact that a particular method is suitable for one type of a sample does not automatically mean that it will be appropriate for the identification of another sample. Therefore, the aim of the study is to demonstrate the limitations of both Raman Spectroscopy (RS) and infrared spectroscopy in the study of earthy materials.
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