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Stability of humic complexes
Vlašicová, Silvie ; Smilek, Jiří (referee) ; Klučáková, Martina (advisor)
This bachelor thesis is focused on humic acids as an active ingredient of organic soil substance and their interaction with the selected drug, Ibuprofen. The aim of this work was to optimize the methods of drug determination in solutions containing humic acids. Subsequently, adsorption experiments were performer to provide information about the adsorption efficiency depending on the concentration of Ibuprofen. Desorption experiments were then used to determine the stability of humic substance complexes with Ibuprofen, or, more precisely, the proportion of the mobile and bound Ibuprofen fraction in the prepared complexes.
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Behaviour of diclofenac in soil systems
Šmerdová, Kateřina ; Kalina, Michal (referee) ; Klučáková, Martina (advisor)
In these days, a large amount of drugs are not completely removed in wastewater treatment plants, than it enters watercourses and then it leaks into soils. These substances are not natural in the environment, so they can have a negative effects here. This is very important to study the behavior of foreign substances in the environment. In this thesis the sorption and desorption behavior of the commonly used drug diclofenac in the soil system was monitored. The rate of sorption and desorption was determined from the change in diclofenac concentration analyzed by UV-VIS spectrometry. Changes in pH and conductivity were also monitored. Diclofenac showed good sorption properties in all the concentrations. There was no desorption or just a minimal desorption, that indicating a strong bond between diclofenac and soil and less leachability into the soil fusion. The results of this thesis showed, that even if diclofenac leaks into the environment, it is mostly adsorbed into the soil. This is largely positive, because diclofenac is practically harmless in the soil and due to the strong bond it also persist there.
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Liquid-vapor mass exchange in stripping processes
Liman, Martin ; Kalivoda, Josef (referee) ; Svěrák, Tomáš (advisor)
This diploma thesis deals with the solution of ammonia separation from waste raw materials of agricultural production. It focuses on determining the efficiency of desorption from an experimental stripping device depending on the measurement temperature. Ammonia water solutions and liquid digestate samples from technical practice were used to verify the functionality of the equipment. Increasing separation efficiency with increasing temperature has been demonstrated. The device was gradually improved during the measurement for a better profitability of the separation process. The results of the experiments are discussed concerning the theoretical assumptions and compared with other methods of ammonia separation.
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Developement and validation of method for ferulic acid isolation from wheat bran
Nábělek, Jakub ; Obruča, Stanislav (referee) ; Pořízka, Jaromír (advisor)
This master thesis deals with an optimization of processes of isolation of ferulic acid from wheat bran. Process of isolation based on alkaline hydrolysis from the substance and its adsorption was tested. In the theoretical part were described wheat bran, adsorption proces and used methods. For adsorption were tested five types of adsorbents. Especially these adsorbents: activation carbon (2,53 ± 1,16 mg.l-1), Amberlyst A-21 (105,73 ± 11,87 mg.l-1, Amberlit XAD-16 (241,55 ± 10,42 mg.l-1), Amberlit IRA-900Cl (5,90 ± 0,68 mg.l-1) and Amberlit IRA-96 (189,16 ± 6,49 mg.l-1). As the most efficient adsorbent was determine Amberlit XAD-16. The whole process has underwent detailed optimization in order to maximize the purity of the final product. The isolate was characterized by HPLC and FTIR techniques for ferulic acid and related phenolic acids. Based on FTIR analysis was discovered that the isolate was contamined by proteins. A purification procedure based on deproteination of the raw material before the hydrolysis itself was proposed. As the ultimate solution that eliminated the presence of proteins in the isolate was determine ultrafiltration with capture of molecules with Mw > 10 KDa. Ferulic acid yield from one kilo of wheat bran was 1,00 ± 0,22 g.
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Interaction of Ibuprofen with Humic Substances and Stability of Formed Complexes
Vlašicová, Silvie ; Smilek, Jiří (referee) ; Klučáková, Martina (advisor)
Nowadays, huge amounts of drugs get into watercourses and soil due to wrong disposal in sewage treatment plants. In this work, the sorption and desorption behavior of Ibuprofen in the soil system was studied, especially in relation to humic acids. The degree of sorption and desorption was defined from the change in ibuprofen concentration analyzed by UV-VIS spectrometry, changes in conductivity and pH were also observed. Ibuprofen shows good sorption properties, desorption was really minimal. It can be assumed that there is a strong bond between ibuprofen and both soil and lignite humic acids and therefore there is no risk of leaching back into solutions. Therefore, if ibuprofen entered the environment, it would be sorbed into the humic acids contained in lignite or soil, which means that it should not be harmful in any way.
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Interactions and imobilization of pharmaceuticals in soil systems
Šmerdová, Kateřina ; Krouská, Jitka (referee) ; Klučáková, Martina (advisor)
In these days, most non-steroidal anti-inflammatory drugs (NSAIDs), including diclofenac (DK), are considered as environmental contaminants. In this thesis, the sorption and desorption mechanisms of diclofenac in soils with different organic matter content were studied. The pH of the medium and its effect on DK adsorption by Britton – Robinson buffer were also studied. Last but not least, the spontaneous degradation of DK in water under sunshine was observed; depending on similar studies, the photodegradation product has been described. The value of pH and conductivity of all the samples were monitored continuously throughout the experiment. It has been found that the content of soil organic matter has a colossal influence on the drug sorption and desorption. Studied soil with a higher content of organic matter recorded higher adsorption of DK in all monitored koncentration of DK. Different pH values also affected the sorption and desorption of DK. By results, a neutral and alkaline environment supports the adsorption of DK more than an acidic environment. The samples were analyzed by UV-VIS spectrophotometry. Photodegradation of DK in water was successful after 4 months. The degradation product was analyzed by UV-VIS spectrophotometry and FTIR spectrometry. The product of fotodegradation could probably be carbazole derivative.
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Analysis of Nanostructures by ToF-LEIS
Duda, Radek ; Král, Jaroslav (referee) ; Mašek, Karel (referee) ; Dub, Petr (advisor)
The presented thesis deals with the utilization of TOF-LEIS analytical method in the area of nanostructure analysis. A new procedure for depth profiling of the elemental composition of the sample, based on the alternate measurement with the DSIMS method, was established. The TOF-LEIS method is able to detect the interface between the layers before its mixing by the ion beam of the DSIMS method. Furthermore, a procedure of TOF-LEIS spektra modification was established to obtain the actual concentration of elements in the sample by reduction of a multiple collision contribution. By comparison of TOF-LEIS spectra with the results received by the DSIMS method the ratio of molybdenum and silicon ion yields was obtained. In the next section advantages of the TOF-LEIS method in combination with XPS during analysis of thermal stability of gold nanoparticles are presented. The mutual complementarity of both methods is shown and final conclusions are supported by electron microscopy images. The final section deals with a newly assembled apparatus for the TOF-SARS analytical method and shows its possibilities regarding the detection of hydrogen on the graphene.
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Wastewater stripping with the support of simulation software
Mader, Dan ; Touš, Michal (referee) ; Vondra, Marek (advisor)
The issue of increasing nitrogen in wastewater and at the same time growing demand for nitrogen fertilizers can be interconnected and solved by using stripping technology. This thesis deals with testing and modifications of the experimental unit for ammonia stripping in the Laboratory of Energy Intensive Processes, as well as the creation of a simulation of this unit in software ProMax. The batch mode unit was converted to continuous operation after several experiments with ammonia solution. The outcomes of the measurements from batch and continuous operation as well as from the simulation were subsequently compared and the obtained data show that continuous operation currently allows the removal of 94% of ammonia from the total input amount, while batch operation up to 98%. However, according to the simulation results, the lower efficiency of the continuously operating unit can be changed when certain operating parameters are increased. This knowledge can be used for further experiments or design of an industrial stripping column.
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Wastewater stripping with the support of simulation software
Mader, Dan ; Touš, Michal (referee) ; Vondra, Marek (advisor)
The issue of increasing nitrogen in wastewater and at the same time growing demand for nitrogen fertilizers can be interconnected and solved by using stripping technology. This thesis deals with testing and modifications of the experimental unit for ammonia stripping in the Laboratory of Energy Intensive Processes, as well as the creation of a simulation of this unit in software ProMax. The batch mode unit was converted to continuous operation after several experiments with ammonia solution. The outcomes of the measurements from batch and continuous operation as well as from the simulation were subsequently compared and the obtained data show that continuous operation currently allows the removal of 94% of ammonia from the total input amount, while batch operation up to 98%. However, according to the simulation results, the lower efficiency of the continuously operating unit can be changed when certain operating parameters are increased. This knowledge can be used for further experiments or design of an industrial stripping column.
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Interactions and imobilization of pharmaceuticals in soil systems
Šmerdová, Kateřina ; Krouská, Jitka (referee) ; Klučáková, Martina (advisor)
In these days, most non-steroidal anti-inflammatory drugs (NSAIDs), including diclofenac (DK), are considered as environmental contaminants. In this thesis, the sorption and desorption mechanisms of diclofenac in soils with different organic matter content were studied. The pH of the medium and its effect on DK adsorption by Britton – Robinson buffer were also studied. Last but not least, the spontaneous degradation of DK in water under sunshine was observed; depending on similar studies, the photodegradation product has been described. The value of pH and conductivity of all the samples were monitored continuously throughout the experiment. It has been found that the content of soil organic matter has a colossal influence on the drug sorption and desorption. Studied soil with a higher content of organic matter recorded higher adsorption of DK in all monitored koncentration of DK. Different pH values also affected the sorption and desorption of DK. By results, a neutral and alkaline environment supports the adsorption of DK more than an acidic environment. The samples were analyzed by UV-VIS spectrophotometry. Photodegradation of DK in water was successful after 4 months. The degradation product was analyzed by UV-VIS spectrophotometry and FTIR spectrometry. The product of fotodegradation could probably be carbazole derivative.
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