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The influence of different anions on fixation of Cu in alkali-activated blast furnace slag
Böhm, Petr ; Kotrla, Jan (referee) ; Koplík, Jan (advisor)
The work deals with the fixation of copper in alkali activated blast furnace slag and with the influence of anionts (sulphate, nitrate, chloride and oxide) to its immobilization. This is tested according to leaching tests ČSN EN – 12457 4. The concentration of copper in leachates was determined by inductively coupled plasma optical emission spectrometry. The aim of this work is to check the influence of addition (copper) to the resulting mechanical properties and also specify, how the heavy metal is bonded in the matrix. The structure was examined by scanning electron microscopy.
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Immobilization of heavy metals in the cement matrix with the admixture of natural zeolite
Semerádová, Nikol ; Bayer, Patrik (referee) ; Vyšvařil, Martin (advisor)
Heavy metals released to the natural ecosystem constitute significant risks not only for organisms, but also for water supplies in the nature. There are a number of analytical methods for the determination of heavy metals. Each of them is suitable for different element and its character. Since the results of the analysis are applied during the solidification and stabilization, it is necessary to ensure the highest correlation between hazardous waste and solidification medium for maximum inhibition of toxic ions. This work investigates the stabilization of heavy metals binders based on cement base with admixture of the natural zeolite and its possible use for the solidification of heavy metals in soluble form.
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Wood Extractive Compounds - Extraction, Chemical composition, Biological activity, Native durability =: Extraktivní látky dřeva: Extrakce, Chemické složení, Biotická aktivita, Přirozená trvanlivost /
Sablík, Pavel
Wood chemical composition research is of significant importance for various fields like wood-manufacturing, food and pharmaceutical industries. Much research work has been motivated by the fundamental knowledge that wood of some tree species demonstrate significantly higher native durability against biological degradation and therefore is much convenient to use in more demanding applications, e.g. in contact with soil or water. This important wood property was assign mainly to presence of extractive chemical compounds or secondary metabolites, produced by wood when heartwood is formed. The presented doctoral thesis aims to find the possibilities of how to utilize extractive chemical compounds found in Black locust (Robinia pseudoacacia L.) as treatment solutions. These can be used to increase the durability of low durable wood species. The experimental part of the presented thesis was carried out using the laboraties and equipment of the Mendel University in Brno, and their external laboratories of research centre in Útěchov. Paper 01 aims to establish methodology for extraction apparatus fexIKA. Describes mainly possibilities for quantitative gains of extractives when using various organic solvents. Within this papers research scope heartwood, sapwood and bark of Black locust were used as the source material. Black locust was choosen mainly due to its extremely high native durability, together with oak considered highest in Central Europe, and for longer term experimental plans and reason. The established methodology for primal solvents (acetone, benzene, cyclohexane, ethanol and distilled water) was the result of this paper. The influence of extraction inputs (particles size, solvent type and temperature) on quantitative and qualitative result of extraction process was the topic for research design presented in Paper 02. In the paper comparable results with literature and established fexIKA methodology were proven. Also the effect of the above mentioned inputs are described and extracted chemical content was identified using HPLC-HRMS technique. The possibility of utilizing chemical compounds obtained, based on Paper 01 extractive methodology, aimed for higher content of phenolic compounds according to Paper 02 results, were the topic of Paper 03. This research paper proves antifungal activity of Black locust (Robinia pseudoacacia L.) and African padauk (Pterocarpus soyauxii Taub.) extracts after impregnation into European beech (Fagus sylvatica L.) sapwood. This wood species is assessed as class 5 (not durable), with an average mass loss result after the durability test of untreated samples 43.6 %. Native durability of European beech wood was significantly improved after impregnation with extractives, mass loss resulted in average 12.7 %. This revalued treated beech sapwood into durability class 3. Paper 04 continues with a study of extractives retention in wood matrix after impregnation whilst introducing adjusted leaching tests. Despite standard EN 84, this research employed miniaturized Bravery wood blocks for impregnation and leaching tests, which were at the end shortened to 144 hours. In order to increase the biologicaly active chemical compounds retention in the specimens, heat treatment was used. The results of the experiment proved the significance between heat treatment and retention.
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The influence of different anions on fixation of Cu in alkali-activated blast furnace slag
Böhm, Petr ; Kotrla, Jan (referee) ; Koplík, Jan (advisor)
The work deals with the fixation of copper in alkali activated blast furnace slag and with the influence of anionts (sulphate, nitrate, chloride and oxide) to its immobilization. This is tested according to leaching tests ČSN EN – 12457 4. The concentration of copper in leachates was determined by inductively coupled plasma optical emission spectrometry. The aim of this work is to check the influence of addition (copper) to the resulting mechanical properties and also specify, how the heavy metal is bonded in the matrix. The structure was examined by scanning electron microscopy.
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Immobilization of heavy metals in the cement matrix with the admixture of natural zeolite
Semerádová, Nikol ; Bayer, Patrik (referee) ; Vyšvařil, Martin (advisor)
Heavy metals released to the natural ecosystem constitute significant risks not only for organisms, but also for water supplies in the nature. There are a number of analytical methods for the determination of heavy metals. Each of them is suitable for different element and its character. Since the results of the analysis are applied during the solidification and stabilization, it is necessary to ensure the highest correlation between hazardous waste and solidification medium for maximum inhibition of toxic ions. This work investigates the stabilization of heavy metals binders based on cement base with admixture of the natural zeolite and its possible use for the solidification of heavy metals in soluble form.
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