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Fractional composition of metal ions in humic gels
Potočková, Jana ; Gregorová, Eva (referee) ; Klučáková, Martina (advisor)
This thesis deals with bond strength of metal ions in humic gels. Several samples of humic acids were studied to consider influence of samples isolation process and their consequent characteristics on bond strength of metal ions in their complexes. Some functional groups was blocked by methylation at some samples. Amount of active functional groups in individual samples was determined by standard titration methods. Metal ions bound in humic complexes were divided into several fractions by extraction with different reagents (distilled water, 1M MgCl2, 1M HCl and 0,025M NH4EDTA). Two extraction methods were used: sequential and fractional. During the fractional extraction leaching of metal ions always proceeds in single agents from original komplex, whereas during the sequential extraction leaching proceeds gradually in all extraction agents in order according to rising afinity of agents, i.e. bond strength of metal ions in samples. Amount of metal ions in leaches after extractions was analysed by UV-VIS spektrometry.
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Characterization of methylated humic acids
Solná, Irena ; Kislinger, Jiří (referee) ; Klučáková, Martina (advisor)
The main concern of this bachelor thesis was a characterization of the properties of methylated humic acids. Retrieval on modifications of acidic functional groups of humic substances was done. In addition appropriate experimental methods for assessing the impact of methylation of carboxylic groups of humic acids were selected. Methylation of formentioned carboxylic groups is used to improve stability of humic acids while working with them. The sample of methylated humic acids, produced by the University of Poitiers in France, was investigated by the following methods: UV-Vis spectroscopy, FT-IR spectroscopy, fluorescence spectroscopy and thermal analysis - TGA, DSC. The degree of methylation of carboxylic functional groups of methylated humic acids was considered using an indirect titration. Results were trade-off with the sample without methylation. The impact of gelation on properties of methylated and non-methylated humic acids was also studied.
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Fractional composition of metal ions in humic gels
Potočková, Jana ; Gregorová, Eva (referee) ; Klučáková, Martina (advisor)
This thesis deals with bond strength of metal ions in humic gels. Several samples of humic acids were studied to consider influence of samples isolation process and their consequent characteristics on bond strength of metal ions in their complexes. Some functional groups was blocked by methylation at some samples. Amount of active functional groups in individual samples was determined by standard titration methods. Metal ions bound in humic complexes were divided into several fractions by extraction with different reagents (distilled water, 1M MgCl2, 1M HCl and 0,025M NH4EDTA). Two extraction methods were used: sequential and fractional. During the fractional extraction leaching of metal ions always proceeds in single agents from original komplex, whereas during the sequential extraction leaching proceeds gradually in all extraction agents in order according to rising afinity of agents, i.e. bond strength of metal ions in samples. Amount of metal ions in leaches after extractions was analysed by UV-VIS spektrometry.
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Characterization of methylated humic acids
Solná, Irena ; Kislinger, Jiří (referee) ; Klučáková, Martina (advisor)
The main concern of this bachelor thesis was a characterization of the properties of methylated humic acids. Retrieval on modifications of acidic functional groups of humic substances was done. In addition appropriate experimental methods for assessing the impact of methylation of carboxylic groups of humic acids were selected. Methylation of formentioned carboxylic groups is used to improve stability of humic acids while working with them. The sample of methylated humic acids, produced by the University of Poitiers in France, was investigated by the following methods: UV-Vis spectroscopy, FT-IR spectroscopy, fluorescence spectroscopy and thermal analysis - TGA, DSC. The degree of methylation of carboxylic functional groups of methylated humic acids was considered using an indirect titration. Results were trade-off with the sample without methylation. The impact of gelation on properties of methylated and non-methylated humic acids was also studied.
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