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Utilization of flow-through coulometry for study of reactivity of humic acids
Pavlíková, Marcela ; Sýkorová,, Ivana (referee) ; Klučáková, Martina (advisor)
Humic acids are part of humus material abounded in nature. Humic acids are generally aromatic stuffs with sidechains and there can be linked various functional groups as carboxylic and fenolic mainly. This functional groups are able to form transitions elements ions and complexes of different stability. This property can be used in the environment, because certain polutants should be imobilized in nature. Diploma thesis studies adsorption of metal ions Cu2+, Cd2+, Zn2+ and Pb2+ on humic acids by electroanalytical method called flow – through coulometry.
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Utilization of waste from the food industry for wastewater treatment
Nedvědická, Lucie ; Obruča, Stanislav (referee) ; Diviš, Pavel (advisor)
This bachelor thesis disserts about options and issues how to utilize waste from the food industry for wastewater treatment contaminated with heavy metals. The theoretical part describes the general characteristics of heavy metals, as well as the permissible and limit values of these heavy metals in waste water. Furthermore, it is described in this document which chemical methods can be used in order to remove heavy metals from wastewater. This thesis also deals with methods how to analyze the adsorbed amount of sorbed substance, means by using AAS, AFS, AES, MS and ICP – OES methods. At the end of the theoretical part, the issues of the different wastes from the food industry are dealing with and their adsorption ability. In the experimental section it was investigated the tea waste utilization in order to eliminate copper ions from waste water. It has been tested mainly the effect of pH on the adsorption of copper onto tea waste and maximum possible adsorption capacity onto tea waste. The pH optimum for the sorption of cooper from solution onto tea waste was within range 5-6 and the maximum possible adsorption capacity 0,0336 mmol•g-1 was determined. The results indicate that the tea waste could be used as a suitable adsorbent for the purification of waste water, mainly due to good availability, low cost and good adsorption ability of heavy metals.
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Reactivity of modified humic gels
Lang, David ; Sedláček, Petr (referee) ; Klučáková, Martina (advisor)
This bachelor thesis deals with humic acid gels and their ability to bind metallic ions on their surface. In the thesis the adsorption of copper ions on humic gels was studied. The gels were prepared by dissolving the humic acid in sodium hydroxide or sodium tripolyphosphate and then by precipitating with hydrochloric acid or magnesium chloride. Adsorption was studied at different concentrations of the copper (II) chloride and measured on UV-VIS spectrophotometer. It was proved from measuring that gels made from sodium tripolyphosphate are adsorbing less copper ions than the ones prepared by sodium hydroxide. Also, the copper ions are bound with smaller force on gels prepared with polyphosphate. Gels precipitated with magnesium chloride adsorb much more than gels precipitated with acid, Thus the extracted amounts are bigger.
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Activated carbon adsorption
Vrána, Tomáš ; Dvořák, Radek (referee) ; Solodyankin, Kirill (advisor)
The objective of this bachelor’s thesis is the description of the Activated carbon adsorption. It’s here division activated carbon according to form and using. Further then description adsorption from fluent and from liquid phase on activated carbon. There are here reffered to factors influencing adsorption. At last chapter is comparing effectiveness adsorption near activated carbon, zenotil and silica gel.
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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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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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Adsorption of metal ions on humic acids
Pokorná, Markéta ; Mgr. Martina Havelcová, Ph.D (referee) ; Klučáková, Martina (advisor)
The Bachelor´s thesis deals with humic acids and their ability to bind metal ions on their surface. Humic acids are generally aromatic polycyclic compounds, which contain phenolic and carboxylic functional groups on their sidechains. Because of their functional groups, they are able to form stable complex compounds. In this thesis, the adsorption of lead ions was studied by electroanalytical method called flow-through coulometry.
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Study of interactions of organic matter and its components via molecular dynamics
BARVÍKOVÁ, Hana
Humic acids and humates are principal components of humic substances major organic constituents of soil, peat, coal and water around the world. I was involved in research into molecular dynamics simulations of interactions of quartz surfaces with aqueous solutions of ions and small organic molecules representing basic building blocks of larger biomolecules and functional groups of organic matter. We studied interactions of molecules with surfaces for a set of surface charge densities corresponding to the experimentally or environmentally relevant ranges of pH values employing molecular mechanics, molecular dynamics and ab initio techniques. Simulated quartz surfaces covered the range of surface charge densities 0.00, -0.03, -0.06 and -0.12 C-m-2, approximately corresponding to pH values 4.5, 7.5, 9.5 and 11. As model molecules, benzoic acid, phenol, o-salicylic acid and their conjugated bases were chosen. My task was to prepare topologies and parametric models of selected organic matter basic building blocks organic molecules. I focused on studying interactions of these molecules in an aqueous environment with mineral surface quartz. The aim was to process simulation results and analyse conformations of the adsorption complexes and their thermodynamic properties such as interaction energies, free energies and adsorption geometries.
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Computer simulation of interactions of molecules with mineral surfaces
BARVÍKOVÁ, Hana
This thesis is focused on molecular dynamics, modelling interactions and their simulation. One of the tasks was to familiarize with GROMACS, a molecular dynamics simulation software. This work also introduces the basics of molecular dynamics and modelling interactions of organic molecules with mineral surfaces. The aim of the thesis was to solve model tasks in GROMACS and analyze the output results. The thesis describes some of the most important file formats and utilities that are needed for working with GROMACS and the use of both the formats and the utilities. In this program, I built up several systems consisting of combinations of organic molecules such as benzoic acid, phenol, salicylic acid and their conjugate bases with mineral surfaces (quartz crystal) of different surface charge density. Furthermore I analyzed the results of these simulations, behaviour of the structures and adsorption geometries and interaction energies within these systems. The thesis might also serve as a quick introduction and familiarization with GROMACS with emphasis on simulations and analysis of systems with planar interfaces. Within the MetaCentrum Project I worked on the Hermes Computer Cluster belonging to the Faculty of Science at the University of South Bohemia.
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