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Photocatalytic activity of printed hybrid layers of titanium dioxide
Sýkorová, Kateřina ; Krystyník, Pavel (referee) ; Veselý, Michal (advisor)
The main aim of this thesis was to optimalise composition of the titanium dioxide with a silica binder deposited on a PET foil. Emphasis was put on achieving maximum possible adhesion and hardness of the layer and the effect on photocatalytic activity. For the evaluation of photocatalytic activity comparative experiments with prepared layers were performed. Benzoic acid, dimethyl sulfoxide and azo dye Acid Orange 7 were used as model pollutants. Photocatalytic activity was investigated using UV-VIS spectrophotometry, formal rate constants and degree of conversion were also determined. The study results can be used for removing water pollutants from the water solution.
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Photocatalytic activity of hybrid layers of titanium dioxide for water disinfection
Morávková, Eva ; Krystyník, Pavel (referee) ; Veselý, Michal (advisor)
This bachelor thesis deals with the preparation of thin layers based on nanoparticles of titanium dioxide and organosilica binder. The effect of the ratio of the two components on the properties of the formed immobilized layers is studied. Two different ratios between TiO2 and organosilica binder and two different types of commercially available oxides were used. The work focuses mainly on the formation of thin immobilized TiO2 layers and their properties. Their photocatalytic activity was determined by degradation of model pollutant in solution, as well as their mechanical hardness and layer adhesion were determined. All prepared layers were treated with muffle furnace annealing and UV-C curing. Samples that had undergone a complete treatment were subjected to individual tests. The model dye was Acid Orange 7. Photocatalytic activity was characterized by a formal 1st order rate constant, which was detected by UV/VIS spectrophotometry. Mechanical hardness and adhesion were determined using ISO standards.
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The influence of material composition and spatial arrangement on the properties of photoelectrochemical cells
Pachovská, Martina ; Krystyník, Pavel (referee) ; Dzik, Petr (advisor)
This diploma thesis deals with photoelectrochemical cells containing photoactive titanium dioxide anode and their use for photocatalytic degradation of organic compound from water solutions. The electrical properties of the produced photoelectrochemical cells were determined by the use of voltamperometric characteristics, the oxidation ability of the cells was monitored by measuring the fluorescence of the oxidative intermediates. To study these reactions, benzoic acid was used as the fluorescence probe for OH˙ radicals. The aim of the study was to study the influence of material composition and spatial arrangement of the cathode and the relationship between irradiation, current and rate of electrode processes.
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Removing of organic dyes from water using polyacrylamide hydrogel nanocomposites
Špalová, Anna ; Klusoň, Petr (advisor) ; Krystyník, Pavel (referee)
The unavailability and pollution of water resources have become significant global challenges. Hydrogels composed of cross-linked polymers have emerged as advanced adsorbents for wastewater treatment, owing to their convenient handling and high efficiency. By incorporating appropriate components into the hydrogel structure, the affinity of a specific pollutant to the hydrogel can be modified. Consequently, the resulting hydrogel nanocomposite can display enhanced adsorption capacity, specific selectivity, and other desirable properties. In this thesis, the efficiency of polyacrylamide hydrogel nanocomposites in the removal of organic dyes from water was investigated. Various composites were synthesized, incorporating graphene, kaolin, and laponite. The composition of these composites varied, employing different ratios of monomer to water and monomer to additive. The physicochemical properties of the synthesized hydrogels and their nanocomposites were examined. It was observed that the nanocomposites displayed reduced water-holding capacity compared to pure polyacrylamide hydrogels. The inclusion of additives led to a decrease in nanocomposite rigidity for graphene, minimal alteration in the case of kaolin, and an increase in rigidity for laponite. The compressibility modulus of the samples ranged...
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Material printing upscaling of chemical sensors to R2R techniques
Fanglová, Michaela ; Krystyník, Pavel (referee) ; Veselý, Michal (advisor)
The main task of the diploma´s thesis was to prepare mixtures for printing ozone and UVB sensors. Subsequently, to optimize the compositions and rheological properties of these mixtures for the preparation of chemical sensors for printing by production R2R machnies, including their calibration to detect required doses of ozone and UVB radiation. The experimental study focoused on the laboratory preparation of mixtures for chemical sensors and their subsequent conversion and printing on semi-operational and production R2R machines. The transfer of production to a larger scale was achieved through changes in the rheological properties of the compositions. The prepared ozone sensors were exposed to different ozone doses and their color change was monitored as a function of the ozone dose. The UVB sensors were calibrated to the required UVB dose and their colour response to the UVB dose was monitored.
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Photocatalytic activity of hybrid layers of titanium dioxide for water disinfection
Morávková, Eva ; Krystyník, Pavel (referee) ; Veselý, Michal (advisor)
This bachelor thesis deals with the preparation of thin layers based on nanoparticles of titanium dioxide and organosilica binder. The effect of the ratio of the two components on the properties of the formed immobilized layers is studied. Two different ratios between TiO2 and organosilica binder and two different types of commercially available oxides were used. The work focuses mainly on the formation of thin immobilized TiO2 layers and their properties. Their photocatalytic activity was determined by degradation of model pollutant in solution, as well as their mechanical hardness and layer adhesion were determined. All prepared layers were treated with muffle furnace annealing and UV-C curing. Samples that had undergone a complete treatment were subjected to individual tests. The model dye was Acid Orange 7. Photocatalytic activity was characterized by a formal 1st order rate constant, which was detected by UV/VIS spectrophotometry. Mechanical hardness and adhesion were determined using ISO standards.
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Possibilities of Zn Recovery from Waste Incineration Fly Ashes.
Korotenko, Ekaterina ; Šyc, Michal ; Jadrný, J. ; Mašín, J. ; Krystyník, Pavel ; Klusoň, Petr
Modern economy is characterized by unprecedented increase in the consumption of raw materials and products. Heavy metals represent only 10% of all inorganic goods consumed, but due to their specific physical and chemical properties they are extremely important in everyday life. Zinc is the world's 4th most widely used metal. Due to the reduction of easily accessible natural resources and the growing shortage ofZn, it is necessary to find secondary raw materials and methods to recover metal from them. Fly ash from municipal solid waste incinerators (MSWI) is a suitable raw material for Zn recovery, because of the production quantity and the same content of Zn as in poor ore. Thereby, this paper is aimed to the recovery of Zn from fly ash on the real scale from data obtained from MSWI in the Czech Republic. Verification of the possibility of Zn recovery from fly ash through acid extraction with flue gas treatment system scrubber liquid has been carried out. The results were compared with the published results of Zn recovery using the Swiss technology FLUWA/FLUREC and the Swedish HALOSEP. The average efficiency of Zn extraction in the real MSWI is close to 60%, which is comparable to the efficiency of the technologies mentioned above. Other benefits of acid extraction are above all the neutralization of two hazardous waste streams from the MSWI (fly ash and scrubber liquid), the reduction of chemicals consumption and the total costs for treatment of fly ash and scrubber liquid, production of stabilized inorganic residues and shifting the process in the waste management hierarchy from landfilling towards metals recovery.
Fulltext: content.csg -  PDF
Plný tet: SKMBT_C22019040814151 - PDF
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Removal of Toxic Metals from Contaminated Water by Elektrocoagulation Method.
Mašín, P. ; Krystyník, Pavel ; Klusoň, Petr ; Jadrný, J. ; Krušinová, Z. ; Kroužek, J.
This paper is focused on a pilot scale electrocoagulation method for heavy toxic metal removal from contaminated ground water and waste water. High efficiency, over 99 % removal of ions Cr6+ and Ni2+ (after arise pH to value 9) has been achieved, during treatment groundwater with content 40 respectively 90 mg/l of chromium and nickel. Mainly disadvantage this technology was coating of electrode plate with ferrous oxides or hydroxides and decreasing of heavy metal removal. It was necessary performed periodical flushing with water and regeneration electrode plates helpful solution of H3P04. Following application of electrocoagulation was performed in wastewater produced from leaking of fly ash from incineration plant of municipal waste. Electrocoagulation process was very effective for reducing of Zn and Pb, but decrease of content Cd was only 20 %. It was found, that Cd must be coprecipitated with Na2S and other alternatives are not effective. Thus, for this electrocoagulation technology was found appropriate utilization for effectively reduce of Zn content.\n
Fulltext: content.csg - PDF
Plný tet: SKMBT_C22019040408010 - PDF
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Pilot Scale Testing of Electrocoagulation to Remove Cr6 +, Ni and Zn from Contaminated Groundwater.
Mašín, P. ; Krystyník, Pavel ; Klusoň, Petr ; Krušinová, Z.
Testing has shown a high efficiency in removal of toxic metals, especially chromium (Cr6+ and Crcelk.). The content of contaminants in treated water was mostly under limits for discharging water into the surface water recipient. The pH 4.5 of inlet water was optimal for the electrochemical reduction of Cr6+ to Cr3+ followed by coagulation. Increase of pH was performed in order to increase efficiency of Ni removal. The power input of electrode cells at the current input of 45 A was 1.3 kWh.m-3 of cleaned water. The life of one electrode pack was 35 m3 of contaminated water at mentioned current input.
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