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.

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.

Jihomoravský lignit pocházející z dolu Mír v Mikulčicích, Lignit s.r.o. byl přesítován a vybraná frakce byla modifikována tzv. mokrou cestou pomocí dvou oxidačních (HNO3, H2O2) a dvou „amfifilních“ (kyselina octová, kyselina citronová) činidel. Alkalickou extrakcí byly získány jak huminové kyseliny z neupraveného tak předupraveného lignitu (tzv. regenerované huminové kyseliny). Na základě výsledku elementární analýzy byly vypočítány C/O a C/H poměry, které společně s FTIR spektry podaly informaci o stupni alifaticity/aromaticity a dále o stupni oxidace organického uhlíku. Pomocí vysokoúčinné vylučovací chromatografie byla stanovena distribuce velikosti huminových agregátů. K objasnění procesů probíhajících v povrchové vrstvě bylo proměřeno povrchové napětí studovaných roztoků vzorků. Získaná data byla proložena Szyszkowského rovnicí a obdržené parametry poukázaly jak na povrchovou aktivitu jednotlivých huminových kyselin tak i na povahu molekul zodpovědných za snižování povrchového napětí. Pro vzájemnou korelaci dat získaných výše zmíněnými metodami byl použit Pearsonův korelační koeficient.

Humic acids were extracted from South Moravian lignit. That humic sample was oxidized by either H2O2 or HNO3. In next step, oxidized humic acids were polymerized by formaldehyde in order to obtain cross-linked structures with improved water retention capacity. Affinity to water and water retention capacity of obtained products were studied by thermal analysis (DSC – differential scanning calorimetry and TGA – thermogravimetric analysis). In order to study above-mentioned parameters two different methods were used. First approach represented sorption of water to humic acids from three controlled humidities, for description of those processes TGA measurement was used. Second study was based on the DSC monitoring of water excess sorption. Results obtained from TGA measurements showed an increasing sorption ability with increasing relative humidity of the environment. DSC measurerents in hermetically sealed containers resulted in an increasing content of water bound by humic acids structures. All the modified samples of humic acids (oxidized as well as oxidized and modified by formaldehyde) gave higher retention capacity in comparion with the parental humic sample.

Diploma thesis deals with preparation and characterization of block copolymer PP/PE grafted with itaconic anhydride in melt. Experimental part deals with free radical iniciated grafting of polar monomers onto polyolefins and with potencial applications of grafted polyolefins. Samples of PP/PE grafted with itaconic anhydride were prepared under various conditions in the experimental part. 2,5-dimethyl-2,5bis(tert-buthylperoxy)hexane (Luperox 101) was used as radical iniciator. Grafting was performed in Brabender mixer under conditions: temperature 190-230°C, concentration of monomer 0,25-1 weight percent, concentration of iniciator 0,025 – 2 weight percent, screw speed 30 rpm. The influence of certain parameteres: iniciator concentration, monomer concentration and temperature upon conversion of monomer, value of MFI and homopolymerization of monomer extent was of interest. Presence of anhydride bonded to the polymer backbone was confirmed by FTIR spectroscopy. Concentration of grafted anhydride and conversion of monomer was determined by acid-base titration and confirmed by FTIR spectroscopy.

The aim of the Diploma thesis is to consider an influence of soil management (rotation of crops on arable land and grassland) to quantity and quality of humic substances. These properties are depended not only upon way of soil management, but also upon climatic effects, such are rainfall, temperature, elevation above sea-level, level of underground water and content of clay. Significantly influenced factors are content and form of organic carbon which is very tightly bonded to humic substances. In this work the humic acids content and properties progression was studied in given time period. Also the effect of crop rotations to changes of physical and chemical properties of humic acids in soil environment was observed. Diploma thesis was realized in co-operation with Mendel University in Brno, which supplied elaborating samples. Studied soil samples were taken from humus horizon Cambisol modal Vatín during years 1999–2006, always in autumn. Individual samples were characterized by available analytical methods, which are generally used in humic substances research area. They are especially fluorescence spectrometry, UV-VIS and infrared spectrometry and acid-base and conductometric titrations.

The main object of the diploma thesis is study of interaction beetween humic acids and selected metal ions using calorimetric titration. The research about reactivity of humic substances is done comparing the different models used to describe the variety of properties of humic substances. In experimental part the methods of FT-IR spektrometry, potenciometric and conductometric titration are used to recieve the total acidity and carboxylic acidity of lignite humic acid. The optimalization of isothermic titration calorimetry is done to be used within study of reactivity of humic acids, revealing the best correlation with sols of studied humic acid. The basic organic compounds were used including benzoic acid, ftalic acid, salycilic acid, pyrocatechol and phenol as models of bonding groups in humic acids. The reaction enthalpy was calculated from the titration of models and results were compared with semiempiric quantum chemistry calculations following INDO method.

This diploma thesis deals with humic acid gels and their ability to bind metallic ions on their surface. In the thesis, there was studied the adsorption of copper ions on the provided gels. The gels were prepared by dissolving the humic acid in sodium hydroxide or sodium tripolyphosphate and then precipitated with hydrochloric acid or metal chlorides. 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 in the case of gels sequestered metal ions extracted higher.

The aim of this diploma thesis was the study of relation between chemical and thermal stability of complexes of humic acids with heavy metals, namely nickel, cobalt and copper. Complexes were prepared with metal solutions of three different initial concentrations. Through UV-VIS spectrophotometry were determined adsorbed amounts of incorporated metal ions in the structure of humic acid; it was affirmed that amount of bounded metal ions increases with increasing initial concentration. Chemical stability was determined as an amount of released metal ions, two of extraction agents were used (solution of MgCl2 and HCl), total bounded amount was distribute into three different fractions; residual fraction, strongly bound fraction and mobile and ion-exchangeable fraction. Changes that occured in the structure of humic acids after complexation and extraction were investigated by FT-IR spectrometry. Thermo-oxidative stability was tested through thermogravimetric analysis (TGA) and differential scanning calorimetry. The results of this diploma thesis has showed comparision of complexes of two different humic acids. They have confirmed an impact of each metal ion on thermo-oxidative stability of humic acids. The relation between chemical and thermal stability was compared through correlation of data obtained by these methods.

The content of this diploma thesis is study of interactions between humic acids and model probes (such as organic dyes and ions of heavy metals) by the simple diffusion experiments in diffusion cell. The main aim was to desctibe the influence of charge of different diffusion sonds (solved substances) on interactions with humic acids imobilized in model gel phase. As a appropriete model probe was chosen copper ions (as a representation of heavy metals) and organic dyes (methylene blue, rhodamine, fluorescein and chicago blue). Experimental results could be used to improve knowledge based on natural barier properties of humic acids and to inovate simple diffusion laboratory techniques for characterization of reaktivity of biopolymers in general.