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Adsorption of pesticides onto granular activated carbon in water treatment process
Kopecká, Ivana ; Hnaťuková, Petra (advisor) ; Pivokonský, Martin (referee)
The diploma thesis is aimed at adsorption processes during the removal of pesticides onto granular activated carbon (GAC) in the process of drinking water treatment. Adsorption onto GAC represents an efficient method for pesticides removal. High adsorption efficiency can be significantly reduced due to the occurrence of natural organic matter (NOM) in raw water, which involves AOM (Algal Organic Matter) produced by phytoplankton. Analogous to NOM, AOM probably affects adsorption of pesticides by two different mechanisms - a direct site competition and pore blockage effect, in dependence on the different molecular weight of particular AOM fractions. Equilibrium batch and kinetic adsorption experiments were performed using two types of GAC (Norit 1240 and Filtrasorb 400) and two pesticides (terbuthylazine and alachlor). In order to examine the effect of AOM on adsorption of pesticides, raw GAC and GAC preloaded by AOM were used. The effect of pH on the competitive adsorption of AOM was also evaluated. A solid phase extraction (SPE) method and gas chromatography with electron capture detection (GC-ECD) were used to determine pesticides in water samples. AOM was characterized using fractionation onto sorptive resins. The representation of apparent molecular weights of AOM proteins was determined by...
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Brominated and iodinated disinfection by-products
Bednář, Jiří ; Načeradská, Jana (advisor) ; Kopecká, Ivana (referee)
The reaction of a disinfectant with natural organic matter in the presence of bromides and iodides in raw water intended as a source of drinking water produces brominated (Br-DBPs) and iodinated disinfection by-products (I-DBPs) of water. These tend to be more cytotoxic and genotoxic than their chlorinated analogues. However, little information is available on these products compared to chlorinated ones. Therefore, the aim of this work was to provide an overview of natural and anthropogenic sources of bromine and iodine containing substances, to determine their influence on the formation of brominated and iodinated disinfection by-products, and to compare their cytotoxicity and genotoxicity with chlorinated products. Increasing seawater intrusion into the groundwater drinking water source was found to increase the concentrations of Br-DBPs and I-DBPs by up to thousands of percent. A number of substances can be released from water pipe material depending on the material. These include, for example, tenorite and copper cation released from copper piping, iron cation released from cast iron and steel piping, and bromides and dissolved organic carbon (DOC) released from plastic piping. All of these corrosion products contribute to increasing concentrations of DBPs in the distribution network. Both seawater and...
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Disinfection by-products originating from pesticides
Plachá, Markéta ; Načeradská, Jana (advisor) ; Kopecká, Ivana (referee)
An important step in the treatment of drinking water is disinfection, which serves to remove pathogenic substances. During this process, disinfection by-products can be formed, which are mainly produced from organic natural substances reacting with the disinfectant. However, treated water may also contain anthropogenic substances, such as pesticides, whose disinfection by-products are the subject of this work. From the accessible data of the studies carried out so far, a basic summary of their creation was created, and characteristic properties that are essential for the evaluation of adverse effects on human health and the environment. From the field of organophosphorus pesticides, it was found that pesticides containing a phosphorothioate part can be easily oxidized by chlorine to the corresponding oxone derivative, while organophosphorus pesticides with a phosphate part are very stable in the presence of chlorine. The resulting oxon forms can be more effective inhibitors of acetylcholinesterase than their parent compounds and at the same time be stable enough (more than 24 h) to reach the consumer, on whom they can, however, have a negative effect. At the same time, disinfection by- products from pesticides can be more toxic than the original compounds. These include chloroxon, diazoxon and...
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Applied Mineralogy in Forensic Science field
Kotrlý, Marek ; Matějka, Dobroslav (advisor) ; Kopecká, Ivana (referee) ; Vojtíšek, Pavel (referee)
1 ABSTRACT Surprisingly, applied mineralogy plays an important role in the forensic science field. It is the miner- alogical phases which exist in many kinds of materials and traces but also the mineralogical analysis procedures which are often used in the field of so called trace evidence. For purposes of this study, 4 important fields of forensic microanalysis were chosen. These are those fields in which applied min- eralogy is applied and which characterize the width and heterogeneity of the concerned area. Powder X-ray microdiffraction plays quite an important and irreplaceable role not only in the direct phase analysis of substances in mixtures. The author designed, tested and introduced a set for centra- tion and direct check of the analysed surface during micro-diffraction analysis and also experimentally optimised sensing parameters for the different system configuration. A possibility to calculate the size of the nanoparticles (more precisely the size of a mono crystal domain) was tested. XRD methods ap- plication allows refining organic analysis for example in the case of new synthetic drugs. Micro diffrac- tion was also used for the first complex phase analysis of colour layers of the altar in the chapel in the castle of Křivoklát (dated 1480 - 1490). Forensic analysis of soil phases used to be,...
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Adsorption of organic compounds onto activated carbon in water treatment process
Kopecká, Ivana
The dissertation thesis focuses on the application of activated carbon for the removal of low molecular weight algal organic matter (AOM) produced by phytoplankton during drinking water treatment, as well as on the effect of AOM on adsorption of anthropogenic micropollutants contained in raw water. The results of this study have been published in international peer-reviewed journals in 4 papers and in 2 conference contributions. The efficiency of AOM removal was studied in laboratory equilibrium and kinetic experiments using different types of granular activated carbon and cellular peptides with molecular weight < 10 kDa produced by cyanobacterium Microcystis aeruginosa. It has been previously confirmed that these peptides are removed with difficulty during the conventional water treatment based on coagulation/flocculation processes and therefore, other methods need to be applied for their restriction. The effect of solution properties on peptide adsorption was assessed by the tests at different pH values and at variable ionic strengths. The negative impact of peptides on the adsorption of organic micropollutants present in raw water was simulated using competitive adsorption experiments with herbicides alachlor and...
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Oxidation of compounds produced by cyanobacteria Microcystis aeruginosa and its impact on water treatment by coagulation
Štědrá, Karolína ; Načeradská, Jana (advisor) ; Kopecká, Ivana (referee)
Due to eutrophication of aquatic environment, massive growth of algae and cyanobacteria occurs and the seasonal algal bloom is formed. Drinking water treatment plants have to deal with the increased amount of cells as well as organic compounds produced by algae and cyanobacteria (so-called AOM). Moreover, the presence of AOM causes a reduction in the efficiency of coagulation, which is an essential process in drinking water treatment. To increase coagulation efficiency, supportive methods, such as ozone oxidation, are added usually prior to coagulation. While many studies focused on the ozonation of algal and cyanobacterial cells, little is known about the effect of ozonation on AOM. This diploma thesis focused on the evaluation of the effect of ozonation in combination with coagulation on the removal of cellular organic compounds (COM) produced by cyanobacteria Microcystis aeruginosa. The effect of ozonation before or after coagulation on COM removal was investigated. The degradation of microcystins, which are naturally contained in the COM sample, was also monitored. Various ozone doses (1 - 10 mg/L) were tested at three pH values - 5, 7 and 9. Two coagulants were utilized - aluminium sulphate and ferric sulphate. Ozonation removed COM negligibly. However, eliminated microcystins, the degradation...
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Applied Mineralogy in Forensic Science field
Kotrlý, Marek ; Matějka, Dobroslav (advisor) ; Kopecká, Ivana (referee) ; Vojtíšek, Pavel (referee)
1 ABSTRACT Surprisingly, applied mineralogy plays an important role in the forensic science field. It is the miner- alogical phases which exist in many kinds of materials and traces but also the mineralogical analysis procedures which are often used in the field of so called trace evidence. For purposes of this study, 4 important fields of forensic microanalysis were chosen. These are those fields in which applied min- eralogy is applied and which characterize the width and heterogeneity of the concerned area. Powder X-ray microdiffraction plays quite an important and irreplaceable role not only in the direct phase analysis of substances in mixtures. The author designed, tested and introduced a set for centra- tion and direct check of the analysed surface during micro-diffraction analysis and also experimentally optimised sensing parameters for the different system configuration. A possibility to calculate the size of the nanoparticles (more precisely the size of a mono crystal domain) was tested. XRD methods ap- plication allows refining organic analysis for example in the case of new synthetic drugs. Micro diffrac- tion was also used for the first complex phase analysis of colour layers of the altar in the chapel in the castle of Křivoklát (dated 1480 - 1490). Forensic analysis of soil phases used to be,...
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Adsorption of low molecular weight algal organic matter onto activated carbon during water treatment
Fialová, Kateřina ; Pivokonský, Martin (advisor) ; Kopecká, Ivana (referee)
This diploma thesis deals with the study of adsorption of low-molecular components of organic substances produced by phytoplankton - AOM (Algal Organic Matter) on AC (Activated Carbon) during drinking water treatment. For the experimental purpose in this thesis, there were used selected amino acids as low molecular substances of AOM that are difficult to remove by conventional water treatment process by coagulation. As adsorbent, there was used a detailed characterized of granulated activated carbon (GAC) - Filtrasorb TL 830 (FTL830) which is intended directly for the purpose of water treatment. There were realizing the equilibrium batch adsorption experiments with three different model amino acids - arginine (Arg), phenylalanine (Phe) and aspartic acid (Asp). There was investigated the efficiency of removing amino acid depending on the solution temperature and pH. Results of the adsorption experiments have shown that the temperature affects the adsorption efficiency. Adsorption is essentially described as an exothermic process but the adsorption of Arg and Phe from an aqueous solution to GAC occurs more efficiently at higher temperatures. It means that the adsorption is the endothermic process. In the case of Arg adsorption, the temperature was found to influence adsorption efficiency less than...
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