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Mapping the potential of secondary products from the production of titanium white
Nehéz, Samuel Emil ; Šoukal, František (referee) ; Opravil, Tomáš (advisor)
This bachelor’s thesis deals with the use of secondary products from the production of titanium white and its subsequent use during cement production. Secondary products from the production of TiO2 could be regarded as several kinds of sulphate waters, where by their successive neutralization gypsum by-products are prepared. The aim of the bachelor’s thesis was to experiment whether it is possible to use some of these gypsum by-products as solidification retarder in Portland cement. Cement pastes were prepared and subjected to mechanical and analytical examinations. During the mechanical examinations, strength in pressure during bending and strength in pulling for the duration of 60 days were monitored. The material from tested bodies of pastes was reviewed by x-ray difraction analysis after 7 and 28 days. Just as was determined the optimum W/C, initial and final setting time. The prepared samples with the gypsum by-product as their content had some features comparable with commercially used cement.
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Impact of input parameters variation on fabrication of nanoporous alumina
Hriczo, Filip ; Macháčková, Marina (referee) ; Hrdý, Radim (advisor)
This thesis examines and tests acids and conditions, which make the production of nanoporous ceramic at the thin aluminium layer the most effective and provide the highest quality. This paper describes the production of nanoporous structures with pore size 15-400 nm, depending on the electrolyte. Creating a regular hexagonal structure by electrochemical oxidation is dependent on many parameters that affect the regularity of structure and parameters of the ceramics produced. They were investigated primarily by changes in temperature and input voltage. All results were examined by SEM analysis.
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Mapping the potential of secondary products from the production of titanium white
Nehéz, Samuel Emil ; Šoukal, František (referee) ; Opravil, Tomáš (advisor)
This bachelor’s thesis deals with the use of secondary products from the production of titanium white and its subsequent use during cement production. Secondary products from the production of TiO2 could be regarded as several kinds of sulphate waters, where by their successive neutralization gypsum by-products are prepared. The aim of the bachelor’s thesis was to experiment whether it is possible to use some of these gypsum by-products as solidification retarder in Portland cement. Cement pastes were prepared and subjected to mechanical and analytical examinations. During the mechanical examinations, strength in pressure during bending and strength in pulling for the duration of 60 days were monitored. The material from tested bodies of pastes was reviewed by x-ray difraction analysis after 7 and 28 days. Just as was determined the optimum W/C, initial and final setting time. The prepared samples with the gypsum by-product as their content had some features comparable with commercially used cement.
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Using a modified biocharge to capture ammonia from the exhaust air
Kozlíková, Nikola ; Innemanová, Petra (advisor) ; Cajthaml, Tomáš (referee)
In my work I have dealt with the comparison of different types of biochar based solid materials, which could serve as a filling for ammonia capture filters. Three samples of biochar prepared from anaerobically stabilized sewage sludge were used to test the most suitable material at temperatures of 200 ř C, 400 ř C and 600 ř C, 3 samples of biochar prepared from oak wood at temperatures of 260 ř C, 400 ř C and 600 ř C, 2 samples of biochar prepared from a mixture of sewage sludge and wood chips pre-dried in a pilot scale biological drying plant, dried anaerobically stabilized sewage sludge and charcoal. The materials were impregnated with 50% sulfuric acid solution. They were then exposed to ammonia vapors for the time needed to complete the reaction on the surface of the impregnated material. Due to the chemical reaction, ammonium sulfate is produced, which can be used as a fertilizer in agriculture. It is known that the addition of biochar has a positive effect on the soil. In the case of a combination of biochar and ammonium sulphate, this may be an interesting soil additive. It could be an alternative to so-called scrubbers, where ammonia is trapped by bubbling dilute sulfuric acid. Transportation and application of the ammonium sulphate solution thus formed is not economically advantageous. To...
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Impact of input parameters variation on fabrication of nanoporous alumina
Hriczo, Filip ; Macháčková, Marina (referee) ; Hrdý, Radim (advisor)
This thesis examines and tests acids and conditions, which make the production of nanoporous ceramic at the thin aluminium layer the most effective and provide the highest quality. This paper describes the production of nanoporous structures with pore size 15-400 nm, depending on the electrolyte. Creating a regular hexagonal structure by electrochemical oxidation is dependent on many parameters that affect the regularity of structure and parameters of the ceramics produced. They were investigated primarily by changes in temperature and input voltage. All results were examined by SEM analysis.
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Modelling of Sulfuric Acid Nanoparticles Growth
Škrabalová, Lenka ; Brus, D. ; Antilla, T. ; Ždímal, Vladimír ; Lihavainen, H.
Aerosol particles influence global radiative balance and climate directly through scattering and absorbing solar radiation and indirectly by acting as condensation cloud nuclei. The atmospheric nucleation is often followed by a rapid growth of freshly formed particles. The initial growth of aerosol is the crucial process determining the fraction of nucleated particles growing into cloud condensation nuclei sizes (~ 50 nm and larger). The subject of this study is modelling of growth behaviour of sulfuric acid nanoparticles produced by nucleation of water and sulfuric acid under wet and dry conditions.
Fulltext: content.csg -  PDF
Plný tet: SKMBT_C22013101814581 - PDF
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Growth of Sulfuric Acid Nanoparticles at Wet and Dry Conditions
Škrabalová, Lenka ; Brus, D. ; Ždímal, Vladimír ; Lihavainen, H.
Aerosol particles influence global radiative balance and climate directly through scattering and absorbing solar radiation and indirectly by acting as condensation cloud nuclei. The atmospheric nucleation is often followed by a rapid growth of freshly formed particles. The initial growth of aerosol is the crucial process determining the fraction of nucleated particles growing into cloud condensation nuclei sizes (~ 50 nm and larger). Many recent studies have suggested that the sulfuric acid plays a key role in the atmospheric nucleation and subsequent growth of newly formed particles. (Sipilä et al., 2010). The subject of this experimental study is growth behaviour of sulfuric acid nanoparticles produced by homogenous nucleation at wet and dry conditions.
Fulltext: content.csg - PDF
Plný tet: SKMBT_C22012102615341 - PDF
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