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Monitoring the effectiveness of selected adsorbents to remove micropollutants from drinking water
Kabelíková, Eva ; Svoboda,, Miroslav (referee) ; Biela, Renata (advisor)
This diploma thesis deals with the effectiveness of selected adsorbents for the removal of micropollutants from drinking water. In the first part there are described individual types of micropollutants and their occurrence in water. Further, there are described pharmaceuticals and their consumption in the world. At the end of the first part, the possibilities of removing micropollutants in drinking water treatment are approached and two water treatment plants in the Czech Republic have been selected, which already use the technology of the removal of some micropollutants. In the practical part of this diploma thesis is performed an experiment of removal of Ibuprofen from model water by adsorption on selected materials, which are Filtrasorb F100, Bayoxide E33 and GEH.
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Effect of sub-micrometer structural features on rheology of polymer nanocomposites
Lepcio, Petr ; Chodák,, Ivan (referee) ; doc.Ing.Marián Lehocký, Ph.D. (referee) ; Jančář, Josef (advisor)
Polymerní nanokompozity (PNCs) mají slibnou budoucnost jako lehké funkční materiály zpracovatelné aditivními výrobními technologiemi. Jejich rychlému rozšíření však brání silná závislost jejich užitných vlastností na prostorovém uspořádání nanočástic (NP). Schopnost řídit disperzi nanočástic je tak klíčovým předpokladem pro jejich uplatnění ve funkčních kompozitech. Tato práce zkoumá přípravu polymerních nanokompozitů v modelové sklotvorné polymerní matrici roztokovou metodou, technikou schopnou vytvářet prostorové uspořádání nanočástic řízené strukturními a kinetickými parametry přípravného procesu. Prezentované výsledky popisují rozdíly mezi změnami rheologického chování roztoku polystyrenu při oscilačním smyku s vysokou amplitudou (LAOS) vyvolanými nanočásticemi. Výsledky vedou k závěru, že vysoce-afinní OP-POSS nanočástice při nízkých koncentracích dobře interagují s PS a tvoří tuhé agregáty, zatímco nízko-afinní OM-POSS nanočástice za těchto podmínek neovlivňují deformační chování polymerních řetězců. Dále byla pozornost zaměřena na vliv použitého rozpouštědla na uspořádání nanočástic v SiO2/PMMA a SiO2/PS nanokompozitech, který je v literatuře prezentován jako parametr řídící prostorové uspořádání nanočástic v pevném stavu. Důraz byl kladen na kvalitativní rozdíly mezi „špatně dispergovanými“ shluky nanočástic, které byly na základě rheologie a strukturální analýzy (TEM, USAXS) identifikovány jako polymerními řetězci vázané nanočásticové klastry a dva typy agregátů, jeden termodynamického a druhý kinetického původu. Jednotlivé druhy agregátů se vyznačují odlišnými kinetikami vzniku a rozdílnými vlastnostmi jak mezi sebou, tak v porovnání s dispergovanými nanočásticemi. Pozorované typy disperze nanočástic byly kvantitativně posouzeny podle svých rheologických vlastností během roztokové přípravy, podle kterých byla vyhodnocena míra adsorpce polymeru na povrch nanočástic a atrakce ve vypuzeném objemu. Výsledky byly porovnány s teorií PRISM. Důležitost uspořádání nanočástic byla demonstrována na porovnání teplot skelných přechodů různých struktur při stejném chemickém složení.
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Molecular modeling of biomolecules - surface interactions
KROUTIL, Ondřej
Interactions between (bio)molecules, ions and solid surfaces play crucial role in many biological processes as well as in many scientific applications and understanding of this phenomenon on molecular level is a challenging task for today science. Computer simulations can provide detailed view on atomic level if carefully prepared and evaluated models are used. In this thesis, interactions of several types of (bio)molecules with inorganic surfaces are studied by classical and ab initio molecular dynamics. Chemisorbed biomolecules, namely DNA and oligopeptide, covalently attached to graphene and mercury surface, respectively, were studied to make link with DNA chip design and experimental label-free electrochemical measurements, respectively. Quartz (101) surface model applicable to wide range of pH conditions was developed and evaluated against experimental X-ray data. Physisorption of the nucleobases on quartz (101) surface and oxalate dianion on rutile (110) was examined and discussed.
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Adsorption of toxic metals from wastewater to waste material from the food industry
Křikala, Jakub ; Pořízka, Jaromír (referee) ; Diviš, Pavel (advisor)
This thesis was focused on the possibility of secondary utilization of waste material from the wine industry to remove heavy metals from wastewater. In the theoretical part, there were discussed mainly the problems of heavy metals pollution including methods of their removal and ICP-OES detection. Furthermore, the waste material from the wine production and the possibilities of its further processing were discussed there. The primary objective of the experimental part was to characterize the material by IR analysis, optimization of adsorption conditions, isotherms construction and determination of maximum adsorption capacities of white, red and chemically modified marc for Cd, Cr, Cu, Ni and Pb. From the parameters influencing the adsorption efficiency, the adsorbent load was optimized (m/V ratio = 0,02); pH values found were 5 for Cd, Cu, Ni, Pb and 3 for Cr and the contact time to reach the equilibrium was 15 minutes for Cd, Ni, Pb and 30 minutes for Cr and Cu. Maximum adsorption capacity for heavy metals were calculated from adsorption isotherms by applying the Langmuir model and found to be 18,829 7 mg/g for Cd; 10,664 7 mg/g for Ni; 35,602 0 mg/g for Pb (modified marc with 1M NaOH); 4,678 4 mg/g for Cu and 9,629 0 mg/g for Cr. The results of the work confirm the good adsorption potential of heavy metals on marc and the positive effect of chemical modification of natural biosorbents to improve their adsorption capacity.
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Characterization of adsorption properties of probiotic bacteria
Černá, Klára ; Sedláček, Petr (referee) ; Obruča, Stanislav (advisor)
The aim of the diploma thesis is to characterize the adsorption properties of probiotic bacteria. Characterization was performed using of designed and optimized spectrophotometric method of determination of adhesion of probiotic bacteria to mucin as the main viscoelastic component of mucus. In order to provide a more detailed description of the adhesion interactions involved in the adhesion of probiotic bacteria to mucin, the viability of selected probiotic bacterial strains Lactobacillus rhamnosus CCM 1825, Lactobacillus plantarum CCM 7039, Lactobacillus delbrueckii subsp. bulgaricus CCM 7190, Lactobacillus acidophilus CCM 4833, Lactobacillus casei CCM 4798, Bifidobacterium breve CCM 7825, Bacillus coagulans CCM 2658 and a potential probiotic strain of Lactobacillus zeae CCM 7069. Moreover, bacterial adhesion to carbohydrates was also determined for all the bacteria tested. The last proposed and optimized technique was dynamic and electrophoretic light scattering characterizing surface properties such as -potential, average size distribution and isoelectric point. From this method, information was obtained on aggregation of bacterial cells and on electrostatic interactions. The combination of these methods was used as a complex tool to characterize adhesion of the tested bacterial cultures as a very specific, sensitive and key parameter of a successful probiotic microorganism that is influence by the multiple effects.
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Experimental study on the adsorption of bacterial cells on solid surfaces
Kahanovská, Kristína ; Obruča, Stanislav (referee) ; Sedláček, Petr (advisor)
This diploma thesis focuses on an optimalization of simple laboratory model systems which serve as an innovative tool for an experimental study on the adsorption of bacterial cells on solid surfaces. In the description of living biological systems, an adsorption is labelled as an adhesion. Designed model systems were validated with a physical-chemical analysis. Various techniques were used to determine bacteria properties, more specifically Burkholderia cepacia and Bacillus megaterium. The solid surfaces after sorption of bacterial cells of Bacillus megaterium were subjected to a structural and visual analysis. Applying the theoretical approach (e.g. using different physical-chemical models) to study the adhesion of microorganisms to a particular surface allows a prediction of the conditions for a successful adhesion. The results will give us a better understanding of a formation and development of a biofilm.
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Influence of Adsorption on Electrochemical Reduction of Pyridinium Derivatives
Nováková Lachmanová, Štěpánka ; Dupeyre, G. ; Lainé, P. P. ; Hromadová, Magdaléna
Two expanded pyridinium-based compounds 1 and 2 were studied by cyclic voltammetry in two different environments. The nonaqueous solution suppresses the adsorption of the compounds on the electrode surface. Adsorption process in aqueous environment was confirmed by typical shape of the curve as well as by the linear dependence of peak current on the scan rate. The shift of standard redox potential in aqueous solution compared to nonaqueous environment toward more negative potential indicates the adsorption of reactant on the electrode surface. Larger shift observed for flat conjugated molecule 1 confirms its stronger adsorption than for the second molecule.
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Preparation of functionalized polyacetylene networks by one-step polymerization
Trnková, Kristýna ; Sedláček, Jan (advisor) ; Faukner, Tomáš (referee)
Three new compounds of the aromatic-aliphatic Schiff base type have been prepared via a condensation of 4-ethynylbenzaldehyde with various configurational isomers of 1,2- diaminocyclohexane. The compounds contained two azomethine links and two identical ethynyl groups located at terminal benzene rings. By means of a condensation of 4- ethynylaniline with 5-ethynyl-1,3-benzenedicarbaldehyde an aromatic Schiff base has been prepared which contained two azomethine links interconnecting three benzene rings each of which being substituted with one ethynyl group. All the prepared compounds were used as the monomers of the coordination chain growth polymerization in which the ethynyl groups of the monomers were transformed while the azomethine groups remained preserved. The polymerizations provided polymer networks in which the polyacetylene main chains (formed via polymerization) were extensively interconnected with aromatic-aliphatic or aromatic segments containing azomethine groups. The quantitative conversion of ethynyl groups was achieved in the polymerizations of diethynylated monomers. The polymerization of a triethynylated monomer proceeded under the conversion of the ethynyl groups of the monomer up to 90 %. The triethynylated monomer provided networks with microporous texture manifested by a...
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Preparation of Polyacetylene Networks via Postpolymerization Cross-Linking
Šorm, David ; Sedláček, Jan (advisor) ; Zedník, Jiří (referee)
Using the method of chain growth coordination polymerization, the soluble high molecular weight linear poly(3-ethynylbenzaldehyde) has been prepared, which is the polyacetylene type polymer with reactive benzaldehyde pendant groups. The postpolymerization cross-linking of poly(3-ethynylbenzaldehyde) via a condensation reaction with various aliphatic, aromatic-aliphatic and aromatic diamines has been demonstrated as an efficient tool for the transformation of linear poly(3-ethynylbenzaldehyde) to polymer networks. The cross-linking has been proved to proceed under formation of cross-links of the Schiff base type containing two azomethine groups per one cross-link. In dependence on the cross-linking agent the extent of cross-linking varied from 20 to 100 %. Furthermore, the possibility has been demonstrated to cross-link a soluble linear poly[N-(4-ethynylbenzylidene)-4-terc-butylaniline] via postpolymerization transimination reaction with 1,4-phenylenediamine, again, under formation of cross-links of the Schiff base type containing two azomethine groups per one cross-link. A comparison of the covalent structure and texture of the prepared networks has revealed that the post-polymerization cross-linking using condensation reaction of poly(3-ethynylbenzaldehyde) with diamines can provide polymer...
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Magnetic biocomposite materials for removal of significant xenobiotics from water systems
BALDÍKOVÁ, Eva
The theoretical part of this doctoral thesis provides a comprehensive overview on the topic of preparation and subsequent utilization of magnetic derivatives of biological materials for xenobiotic separation from water. Main attention is paid to magnetic modification of waste materials and by-products originating from agricultural and food industry, which represent widely available and low-cost materials, and also to magnetic modification of microbial cells. In addition to the description of magnetic particle preparation and individual developed techniques of magnetic modification, a brief characterization of selected pollutants and a detailed table overview on utilization of magnetically responsive biomaterials for biosorption of organic dyes, heavy metals, pharmaceutical and personal care products together with ubiquitous industrial endocrine disruptors and also of crude oil derivatives is presented. Experimental part of this thesis is focused on the preparation and optimization of new types of magnetic materials. Emphasis is placed on the employment of simple, fast and simultaneously low-cost magnetic modification techniques (e.g., postmagnetization using microwave-synthesized magnetic iron oxides or one-step modification by magnetic fluids). Selected plant materials (barley and rye straw) were chemically modified to significantly (up to five-times) increase the maximum adsorption capacities for tested dyes. All prepared biomaterials exhibited a great magnetic response and simultaneously relatively high adsorption capacity for selected xenobiotics under experimental conditions used. Factors substantially affecting adsorption process, such as pH, initial concentration, incubation time or temperature were also studied. Adsorption equilibrium data were assessed using Langmuir, Freundlich or Sips isotherm models. Experimental data from time dependence study were analyzed by chosen kinetic models, namely the pseudo-first-order and pseudo-second-order ones and by intraparticle diffusion model. Thermodynamic parameters (Gibbs free energy, enthalpy and entropy) describing the nature of adsorption were also included in study.
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