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Preparation of high-valueable gypsum binder
Hájková, Iveta ; Gazdič,, Dominik (referee) ; Fridrichová, Marcela (advisor)
This work is oriented on the preparation of high-voluable sulphate binder based on gypsum waste. One of the potential mineral resources in Moravia is Pregips chemical gypsum, produced by Precheza. This is the raw material, which is characterized by high purity, high quality and is economically acceptable. Beta burned gypsum plaster from this, however, need to modify due to suppression of the high needs of water mixing, which is determined by its morphology. The need for mixing water has a large impact on the strength of gypsum binders. Therefore it is necessary to find a suitable additive, which would reduce the coefficient of water in the preparation of porridge normal consistency.
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Meta-talc Application in Inorganic Materials
Bednárek, Jan ; Rovnaník, Pavel (referee) ; Palou, Martin (referee) ; Havlica, Jaromír (advisor)
This thesis is focused at possibilities of preparation and characterization of XRD-amorphous delaminated and dehydroxylated talc phase – meta-talc, which can have its potential application and a starter material for a preparation of magnesium-silicate analogues of geopolymers. Changes in structure and morphology of talc ore were observed during this work. For the purposes of this research, two various talc ores – chloritic and dolomitic were examined. Whole process of meta-talc preparation was examined with whole scale of instrumental techniques such as X-ray diffraction, simultaneous thermogravimetric a differential thermal analysis, infrared spectroscopy, scanning electron microscopy or laser analysis of particle size. Meta-talc can be obtained via mechanochemical activation of talc ore with subsequent calcination. Mechanochemical treatment lead to destruction of original crystal structure and breaking of original bonds, i.e. the product of this treatment was almost amorphous and delaminated. Most of hydroxyl groups were converted to molecules of water which remained adsorbed or coordinated in ore structure. These molecules were removed during calcination step.
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Hydration Process of Magnesium Oxide from Partly Calcined Dolomite
Tišnovský, Michal ; Bartoníčková, Eva (referee) ; Ptáček, Petr (advisor)
This bachelor thesis deals with the study of half-burnt dolomite, it‘s thermal decomposition (calcination) and preparation of a mixture of magnesium hydroxide and calcium carbonate by precipitation. At the beginning of the experimental part, the dolomite material sample is characterized. It‘s moisture content, double magnesium carbonate content and other carbonates are found. The second part deals with the study of the burning process in which a suitable interval of thermal treatment temperature was found. The investigation of the dissolution of dolomite in hydrochloric acid revealed the reaction kinetics. For precipitation, a method based on boiling a dolomite suspension in a hydrochloric acid solution under reflux, was used. The precipitation product in this case was magnesium carbonate in the modification of aragonite.
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Waste material based high-performance sulphate binders
Hájková, Iveta ; Kolář,, Karel (referee) ; Rovnaníková, Pavla (referee) ; Gazdič, Dominik (advisor)
The topic of this dissertation was the preparation of a high-quality sulphate binder based on secondary raw materials. For this purpose, the work was primarily focused on the laboratory preparation of beta gypsum from the selected industrial gypsum, the design of the technological process of production and its verification by pilot tests. In the next step, the thesis dealt with the modification of beta gypsum by a selected set of liquefiers. In addition to commercial dehumidifiers, the possible beta casting of beta gypsum was tested by increasing the zeta potential of the gypsum suspension. At the end, a complete complex of construction products was developed based on laboratory and semi-prepared beta plasters, consisting of gypsum plasters, mastics, gypsum premix and small plaster casts.
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Use of X-ray diffraction analysis in the optimization of cathode material syntheses for Li-ion batteries
Kunz, Marek ; Čech, Ondřej (referee) ; Chladil, Ladislav (advisor)
This thesis deals with study of structural changes in electrode materials prepared by spray-dry synthesis at different calcination temperatures using X-ray diffraction analysis. In the theoretical part, the work deals with the principle of XRD, parameters that influence the resulting diffractogram and Rietveld analysis. The part further deals with possible syntheses of cathode materials, calcination, and possible ways of battery degradation. The experimental part focuses on investigating the ideal calcination temperature and time of prepared cathode material samples.
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Hydration Process of Magnesium Oxide from Partly Calcined Dolomite
Tišnovský, Michal ; Bartoníčková, Eva (referee) ; Ptáček, Petr (advisor)
This bachelor thesis deals with the study of half-burnt dolomite, it‘s thermal decomposition (calcination) and preparation of a mixture of magnesium hydroxide and calcium carbonate by precipitation. At the beginning of the experimental part, the dolomite material sample is characterized. It‘s moisture content, double magnesium carbonate content and other carbonates are found. The second part deals with the study of the burning process in which a suitable interval of thermal treatment temperature was found. The investigation of the dissolution of dolomite in hydrochloric acid revealed the reaction kinetics. For precipitation, a method based on boiling a dolomite suspension in a hydrochloric acid solution under reflux, was used. The precipitation product in this case was magnesium carbonate in the modification of aragonite.
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Meta-talc Application in Inorganic Materials
Bednárek, Jan ; Rovnaník, Pavel (referee) ; Palou, Martin (referee) ; Havlica, Jaromír (advisor)
This thesis is focused at possibilities of preparation and characterization of XRD-amorphous delaminated and dehydroxylated talc phase – meta-talc, which can have its potential application and a starter material for a preparation of magnesium-silicate analogues of geopolymers. Changes in structure and morphology of talc ore were observed during this work. For the purposes of this research, two various talc ores – chloritic and dolomitic were examined. Whole process of meta-talc preparation was examined with whole scale of instrumental techniques such as X-ray diffraction, simultaneous thermogravimetric a differential thermal analysis, infrared spectroscopy, scanning electron microscopy or laser analysis of particle size. Meta-talc can be obtained via mechanochemical activation of talc ore with subsequent calcination. Mechanochemical treatment lead to destruction of original crystal structure and breaking of original bonds, i.e. the product of this treatment was almost amorphous and delaminated. Most of hydroxyl groups were converted to molecules of water which remained adsorbed or coordinated in ore structure. These molecules were removed during calcination step.
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Waste material based high-performance sulphate binders
Hájková, Iveta ; Kolář,, Karel (referee) ; Rovnaníková, Pavla (referee) ; Gazdič, Dominik (advisor)
The topic of this dissertation was the preparation of a high-quality sulphate binder based on secondary raw materials. For this purpose, the work was primarily focused on the laboratory preparation of beta gypsum from the selected industrial gypsum, the design of the technological process of production and its verification by pilot tests. In the next step, the thesis dealt with the modification of beta gypsum by a selected set of liquefiers. In addition to commercial dehumidifiers, the possible beta casting of beta gypsum was tested by increasing the zeta potential of the gypsum suspension. At the end, a complete complex of construction products was developed based on laboratory and semi-prepared beta plasters, consisting of gypsum plasters, mastics, gypsum premix and small plaster casts.
|
|
|
Preparation of high-valueable gypsum binder
Hájková, Iveta ; Gazdič,, Dominik (referee) ; Fridrichová, Marcela (advisor)
This work is oriented on the preparation of high-voluable sulphate binder based on gypsum waste. One of the potential mineral resources in Moravia is Pregips chemical gypsum, produced by Precheza. This is the raw material, which is characterized by high purity, high quality and is economically acceptable. Beta burned gypsum plaster from this, however, need to modify due to suppression of the high needs of water mixing, which is determined by its morphology. The need for mixing water has a large impact on the strength of gypsum binders. Therefore it is necessary to find a suitable additive, which would reduce the coefficient of water in the preparation of porridge normal consistency.
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