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Modification of soda lignin isolated from winery waste
Chovanec, Martin ; Mikulíková, Renata (referee) ; Kovalčík, Adriána (advisor)
This bachelor thesis provides research on the antibacterial activity of lignin isolated from grape pomace. To separate lignin from grape pomace was used soda lignin isolation method. This method helps to dissolve lignin in the solution of sodium hydroxide. Two isolation procedures were used: 1) isolation by using a conventional laboratory set-up at atmospheric pressure and a temperature of 110 °C and 2) isolation by using a hydrothermal autoclave at increased pressure and a temperature of 110 °C. The hydrothermal autoclave was explicitly developed for this bachelor thesis. Both separations methods were compared from the viewpoint of lignin yields and lignin purity. The lignin yield obtained by using the hydrothermal autoclave was much higher compared to the conventional laboratory set-up, yielding about 36.4 g of soda lignin per 100 g of grape pomace. The infrared spectroscopy analysis of both lignins showed that lignin received by using the conventional laboratory set-up was mixed with hemicelluloses and cellulose. The isolation by using the hydrothermal autoclave enabled to prepare lignin with higher purity. Lignin isolated from grape pomace did not show any antimicrobial activity. The antimicrobial activity was reached after modification of lignin with silver particles in situ. Antimicrobial activity was tested against Bacillus subtilis, Escherichia coli, Micrococcus luteus, Serratia marcescens, Saccharomyces cerevisiae and Candida glabrata. The lignin/silver compound showed the antibacterial activity against all tested bacteria, however no antimicrobial activity against yeasts.
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Effective use of industrial waste in building materials
Szép, Melinda Klaudia Virág ; Mészárosová, Lenka (referee) ; Černý, Vít (advisor)
This bachelor´s thesis deals with one of current topics, namely to effective use of industrial waste in building materials. The theoretical part of this work presents changes in legislation of the Czech Republic in field of waste management system, explains the most important terms and defines each method of waste management. The main goal of this work was to formulate a methodological procedure for efficient use of industrial waste. The methodological procedure was compiled on the basis of elaborated base set of possible variants of waste utilization in the construction sector and a set of corresponding criteria of standards and legislative criteria. A table of elementary criteria has also been compiled for the better orientation in corresponding standards. The proposed methodological procedure was demonstrated on specific example, in fact on slag from municipal waste incineration. The slag was examined in two environments – one with standard laboratory condition and the second with controlled condition (8 % concentration of carbon dioxide and 80 % of relative humidity) – for better understanding of its behaviour. The expected acceleration of the aging process in the environment with controlled condition was confirmed based on the degree of carbonation. The expected reduction of volume changes of the sample exposed to the controlled condition was also confirmed.
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Magnetic separator
Křupka, Jiří ; Jonák, Martin (referee) ; Malášek, Jiří (advisor)
The aim of this bachelor thesis is to design the structural conception of magnetic separator designated to separate small-sized industrial waste. This report provides an overview of facilities of worldwide manufacturers that are used for magnetic separation of steel scrap. Furthermore, it offers an assessment of variants for technical solutions to structural nodes of magnetic separator; this is followed by a selection of specific solution. According to the input parameters, all the parameters necessary for correct machine design are computed. These computations also include the justification of selected table values, placement, surface roughness, geometric tolerances, materials and heat treatment of the individual parts and assemblies. Attachments to this technical report are documentation drawings of selected parts and assemblies.
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Elastomer fillers as a potential raw material for concrete and mortar products
Jankech, Filip ; Balog, Oliver (referee) ; Bodnárová, Lenka (advisor)
To attain a sustainable development in the field of building materials, it is necessary to consider environmental, economic, and social aspects of the industrial production. This thesis addresses the first two aspects. Both theoretical and practical research were implemented in order to study the possibility to replace the commonly used RDPs, that are being used in the dry-mix mortar industry as a primary additive, with the industrially processed elastomer waste materials, such as recycled tire rubber. The review of the scientific literature processed within the theoretical research discloses the state of the art in the field of polymer modification of the mortar products and the effect of the commonly used modifiers and elastomer fillers on the performance of mortar and concrete products. The experimental research was implemented to study the possibility of the replacement of the RDPs for the elastomer fillers. The performance of fresh and hardened mortar containing various amounts of elastomer particles was studied. The results indicate, that the partial replacement could be feasible without worsening the performance of the product.
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Functional technical materials modified by lignin isolated from winery by-products
Chovanec, Martin ; Sedláček, Petr (referee) ; Kovalčík, Adriána (advisor)
In this thesis, the possibility of producing composites of epoxy resin and lignin isolated from grape skins was examined. The motivation was to reduce the amount of bisphenol A, which is nowadays used to produce most of the epoxy resins and is the main environmental pollutant. The composites were prepared by mixing commercial bisphenol A diglycidylether (DGEBA) with lignin samples. In this work, the sodium hydroxide pulping method in a hydrothermal autoclave was used to isolate lignin. The content of reducing sugars, lignin, and fatty acids in the sample of grape skins was determined and the chemical composition was determined by Fourier transform infrared spectroscopy (FT-IR). The chemical and thermal properties of isolated soda lignin were compared with commercial Kraft lignin and analyzed by elemental analysis, FT-IR, thermogravimetric analysis, and ash content determination. Epoxidized lignin was prepared by three methods, which were compared based on yield, epoxide equivalent, and chemical composition. Samples of unmodified soda lignin and epoxidized soda and Kraft lignins were selected for the preparation of epoxy composites. Experiments have shown that isolated soda lignin was not suitable for the addition to epoxy resins, unlike Kraft lignin. Thermal and viscoelastic properties of the prepared composites with a homogeneous structure were analyzed. It was found that the epoxy composites with added epoxidized Kraft lignin showed lower material stiffness and the glass transition temperature was significantly shifted to lower temperatures.
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Effective use of industrial waste in building materials
Szép, Melinda Klaudia Virág ; Mészárosová, Lenka (referee) ; Černý, Vít (advisor)
This bachelor´s thesis deals with one of current topics, namely to effective use of industrial waste in building materials. The theoretical part of this work presents changes in legislation of the Czech Republic in field of waste management system, explains the most important terms and defines each method of waste management. The main goal of this work was to formulate a methodological procedure for efficient use of industrial waste. The methodological procedure was compiled on the basis of elaborated base set of possible variants of waste utilization in the construction sector and a set of corresponding criteria of standards and legislative criteria. A table of elementary criteria has also been compiled for the better orientation in corresponding standards. The proposed methodological procedure was demonstrated on specific example, in fact on slag from municipal waste incineration. The slag was examined in two environments – one with standard laboratory condition and the second with controlled condition (8 % concentration of carbon dioxide and 80 % of relative humidity) – for better understanding of its behaviour. The expected acceleration of the aging process in the environment with controlled condition was confirmed based on the degree of carbonation. The expected reduction of volume changes of the sample exposed to the controlled condition was also confirmed.
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Functional technical materials modified by lignin isolated from winery by-products
Chovanec, Martin ; Sedláček, Petr (referee) ; Kovalčík, Adriána (advisor)
In this thesis, the possibility of producing composites of epoxy resin and lignin isolated from grape skins was examined. The motivation was to reduce the amount of bisphenol A, which is nowadays used to produce most of the epoxy resins and is the main environmental pollutant. The composites were prepared by mixing commercial bisphenol A diglycidylether (DGEBA) with lignin samples. In this work, the sodium hydroxide pulping method in a hydrothermal autoclave was used to isolate lignin. The content of reducing sugars, lignin, and fatty acids in the sample of grape skins was determined and the chemical composition was determined by Fourier transform infrared spectroscopy (FT-IR). The chemical and thermal properties of isolated soda lignin were compared with commercial Kraft lignin and analyzed by elemental analysis, FT-IR, thermogravimetric analysis, and ash content determination. Epoxidized lignin was prepared by three methods, which were compared based on yield, epoxide equivalent, and chemical composition. Samples of unmodified soda lignin and epoxidized soda and Kraft lignins were selected for the preparation of epoxy composites. Experiments have shown that isolated soda lignin was not suitable for the addition to epoxy resins, unlike Kraft lignin. Thermal and viscoelastic properties of the prepared composites with a homogeneous structure were analyzed. It was found that the epoxy composites with added epoxidized Kraft lignin showed lower material stiffness and the glass transition temperature was significantly shifted to lower temperatures.
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Influence of Waste Diatomite as a Raw Material on the Properties of the Inorganic Foam Glass
Nguyen, Martin ; Sedlačík, Martin ; Sokolář, Radomír ; Opravil, Tomáš
This article deals with the manufacturing process of inorganic foam glass with utilization of waste diatomite as a raw material. The waste diatomite was first subjected to an analysis of chemical and mineralogical composition. The foam glass was formed by a powder sintering method by pressing into pellets with the addition of a foaming agent. After firing, the properties of the foam glass were investigated using an X-ray diffraction analysis, scanning electron microscopy, bulk density, and compressive strength. The possibility of utilization of waste diatomite in raw material mixtures was investigated in accordance with the influence of firing temperature and the resulting properties of inorganic foam glass.
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Modification of soda lignin isolated from winery waste
Chovanec, Martin ; Mikulíková, Renata (referee) ; Kovalčík, Adriána (advisor)
This bachelor thesis provides research on the antibacterial activity of lignin isolated from grape pomace. To separate lignin from grape pomace was used soda lignin isolation method. This method helps to dissolve lignin in the solution of sodium hydroxide. Two isolation procedures were used: 1) isolation by using a conventional laboratory set-up at atmospheric pressure and a temperature of 110 °C and 2) isolation by using a hydrothermal autoclave at increased pressure and a temperature of 110 °C. The hydrothermal autoclave was explicitly developed for this bachelor thesis. Both separations methods were compared from the viewpoint of lignin yields and lignin purity. The lignin yield obtained by using the hydrothermal autoclave was much higher compared to the conventional laboratory set-up, yielding about 36.4 g of soda lignin per 100 g of grape pomace. The infrared spectroscopy analysis of both lignins showed that lignin received by using the conventional laboratory set-up was mixed with hemicelluloses and cellulose. The isolation by using the hydrothermal autoclave enabled to prepare lignin with higher purity. Lignin isolated from grape pomace did not show any antimicrobial activity. The antimicrobial activity was reached after modification of lignin with silver particles in situ. Antimicrobial activity was tested against Bacillus subtilis, Escherichia coli, Micrococcus luteus, Serratia marcescens, Saccharomyces cerevisiae and Candida glabrata. The lignin/silver compound showed the antibacterial activity against all tested bacteria, however no antimicrobial activity against yeasts.
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Elastomer fillers as a potential raw material for concrete and mortar products
Jankech, Filip ; Balog, Oliver (referee) ; Bodnárová, Lenka (advisor)
To attain a sustainable development in the field of building materials, it is necessary to consider environmental, economic, and social aspects of the industrial production. This thesis addresses the first two aspects. Both theoretical and practical research were implemented in order to study the possibility to replace the commonly used RDPs, that are being used in the dry-mix mortar industry as a primary additive, with the industrially processed elastomer waste materials, such as recycled tire rubber. The review of the scientific literature processed within the theoretical research discloses the state of the art in the field of polymer modification of the mortar products and the effect of the commonly used modifiers and elastomer fillers on the performance of mortar and concrete products. The experimental research was implemented to study the possibility of the replacement of the RDPs for the elastomer fillers. The performance of fresh and hardened mortar containing various amounts of elastomer particles was studied. The results indicate, that the partial replacement could be feasible without worsening the performance of the product.
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