|
|
Alcohols utilization as non - freezing heat transfer liquids
Kořínková, Klára ; Bednařík, Karel (referee) ; Kotlík, Josef (advisor)
This bachelor´s thesis deals with the alcohols used by the non-freezing heat transfer fluid. Were compared alcohols methanol, ethanol, ethane-1,2-diol, propane-1,2-diol and propane-1,3-diol. The substances were examined mainly from the toxicological point of view and negative impacts on human health. Toxic substance was determined by ethane-1,2-diol. Propane-1,2-diol is the most used substance in the market which is non-toxic.
|
|
| |
|
|
The usage of OECD tests for determination of waste ecotoxicity
Zálešáková, Ludmila ; Zlámalová Gargošová, Helena (referee) ; Bednařík, Karel (advisor)
In my bachelor thesis I consern myself with tests of waste ecotoxicity that are recommended by OECD. The main purpose of the thesis is to characterize these tests and compare them from the application aspect. The thesis presents OECD, its establishment and relation to the Czech Republic. Waste problems are discussed here too. Fundamental terms in this field, sorts of waste and its origin are defined here. The main attention is focused on ecotoxicological tests that are characterized according to their application, implementation and testing organism.
|
|
|
Possibilities of reprocessing of the glycol and glycerol waste into suitable materials
Hýža, Bohumil ; Bednařík, Karel (referee) ; Kizlink, Juraj (advisor)
At the beginning of the thesis is summarized biodiesel production and its world production. There is more developed biodiesel production in the Czech Republic and in the European Union and some European legal regulations and standards for biodiesel. Also described herein is a composition of biodiesel and the description of the technology of its production. In the theoretical section summarizes the physical and chemical properties of glycerol and there is also summarized the traditional use of glycerol as food, explosives, etc. There are also new procedures that were performed in the experimental part of the thesis. Then, here are the proposed new procedures for processing waste glycerol and glycol, which were conducted in the experimental part of the thesis. There are described the ion exchange properties of the cation exchangers and also properties of salts generated by neutralization of NaOH in the waste glycerol with organic acids and CO2. There is also described wood protection, properties of ethylene glycol as coolant and properties of boroglycerols and boroglycols as protection for wood and mechanism of their preparation. Then there is described a mechanism of dehydration of glycerol to acrolein and options which can perform the synthesis. In the experimental part, the pH of waste glycerol was measured and then was measured the amount of NaOH in the waste glycerol. There is also desribed cleaning of waste glycerol from NaOH using acidic cation exchange resins on columns, or by neutralization with oleic acid, lactic acid and CO2. Further syntheses were performed glycerol borate and ethylene glycol borate. Water amount in ethylene glycol and methanol with water amount in glycerol were found by distillation. Then were prepared boroglycol and boroglycerol. By the amount resulting from the amount of reaction water were observed reaction conditions H3BO3, Na2B4O7•10 H2O and glycerol. At the end was carried out experimental dilution resulting boroglycerol and boroglycol by ethanol, methanol, TMB. Finally, the diluted boroglycerol was deposited on wood. Dehydration of glycerol to acrolein under the catalytic action of KHSO4 was performed. The results are given all the results and discussed the possibility of using the knowledge gained in this work in the industry. In conclusion, there are listed the economic comparison using waste glycerol and crude oil as a raw material and also charts the development of oil prices in 40 years since 1970, and graph of the price of waste glycerol. There is also discussed technological applicability of the methods used in practice.
|
|
|
Chemistry of polynitro heterocyclic compounds
Kubátková, Nela ; Bednařík, Karel (referee) ; Friedl, Zdeněk (advisor)
The review of polynitro heterocyclic compounds was written. These are substances with ability to detonate, which is caused mainly by presence of nitrogroups, which are bonded to carbon atoms in their cycles. The thesis deals with common polynitro five-membered heterocycles with one nitro atom, up to six-membered heterocycles with three nitrogen atoms. There are processed basic information of these compounds, as well as their physical-chemical properties and properties of detonation, the possibility of their preparation, which are displayed in the form of chemical reactions.
|
|
|
Toxicity of selected nitramines
Papírek, Jan ; Fojt, Pavel (referee) ; Bednařík, Karel (advisor)
This Bachelor Thesis is focused on determination of toxicity of selected nitramines and nitrosoamines, which had to be synthesized soon. Out of total 10 prepared N-nitro and N- nitrosocompounds 4 were selected for testing their toxicity in test using Duckweed (Lemna Minor). Factor IC50 was determined for two compounds 3,7-dinitro-1,3,5,7-tetraazabicyclo [3.3.1]- nonane (DPT) and 3,7-dinitroso-1,3,5,7-tetraazabyciclo [3.3.1] nonane (DNPT), unfortunately factor for other compounds failed to determine, because conditions of test validity hadn’t been kept. In the end of the thesis is compared toxicity of N-nitro and N-nitrosocompounds based on results and observations.
|
|
|
Possibilities of reprocessing of the glycol and glycerol waste into suitable materials
Hýža, Bohumil ; Bednařík, Karel (referee) ; Kizlink, Juraj (advisor)
At the beginning of the thesis is summarized biodiesel production and its world production. There is more developed biodiesel production in the Czech Republic and in the European Union and some European legal regulations and standards for biodiesel. Also described herein is a composition of biodiesel and the description of the technology of its production. In the theoretical section summarizes the physical and chemical properties of glycerol and there is also summarized the traditional use of glycerol as food, explosives, etc. There are also new procedures that were performed in the experimental part of the thesis. Then, here are the proposed new procedures for processing waste glycerol and glycol, which were conducted in the experimental part of the thesis. There are described the ion exchange properties of the cation exchangers and also properties of salts generated by neutralization of NaOH in the waste glycerol with organic acids and CO2. There is also described wood protection, properties of ethylene glycol as coolant and properties of boroglycerols and boroglycols as protection for wood and mechanism of their preparation. Then there is described a mechanism of dehydration of glycerol to acrolein and options which can perform the synthesis. In the experimental part, the pH of waste glycerol was measured and then was measured the amount of NaOH in the waste glycerol. There is also desribed cleaning of waste glycerol from NaOH using acidic cation exchange resins on columns, or by neutralization with oleic acid, lactic acid and CO2. Further syntheses were performed glycerol borate and ethylene glycol borate. Water amount in ethylene glycol and methanol with water amount in glycerol were found by distillation. Then were prepared boroglycol and boroglycerol. By the amount resulting from the amount of reaction water were observed reaction conditions H3BO3, Na2B4O7•10 H2O and glycerol. At the end was carried out experimental dilution resulting boroglycerol and boroglycol by ethanol, methanol, TMB. Finally, the diluted boroglycerol was deposited on wood. Dehydration of glycerol to acrolein under the catalytic action of KHSO4 was performed. The results are given all the results and discussed the possibility of using the knowledge gained in this work in the industry. In conclusion, there are listed the economic comparison using waste glycerol and crude oil as a raw material and also charts the development of oil prices in 40 years since 1970, and graph of the price of waste glycerol. There is also discussed technological applicability of the methods used in practice.
|
|
|
Possibilities of reprocessing of glycerol layer from the manufacture of bionaphta
Hýža, Bohumil ; Bednařík, Karel (referee) ; Kizlink, Juraj (advisor)
The aim of this thesis was to introduce and apply the possibilities of using waste glycerol from biodiesel production and partly waste low-stiffen coolant from cars that could be applied in industry. At the beginning of the thesis is summarized biodiesel production and its world production. There is more developed biodiesel production in the Czech Republic and in the European Union and some European legal regulations and standards for biodiesel. Also described herein is a composition of biodiesel and the description of the technology of its production. In the theoretical section summarizes the physical and chemical properties of glycerol and there is also summarized the traditional use of glycerol as food, explosives, etc. There are also new procedures that were performed in the experimental part of the thesis. There are described the ion exchange mechanism, ion exchange resin properties and the properties of the acids and salts generated by neutralization with NaOH contained in the waste glycerol. Also is described herein the wood protection and properties of ethylene glycol coolants and properties of boroglycerol and boroglycol as protection for wood and mechanism of their preparation. Next is described the mechanism of dehydration of glycerol to acrolein and options which can perform the synthesis. In the experimental part, the pH of waste glycerol was measured, then was measured the exact amount of NaOH in the glycerol. There is also desribed cleaning of waste glycerol from NaOH using acidic cation exchange resins on columns, or by neutralization with oleic acid, lactic acid and CO2. Further syntheses were performed glycerol borate and ethylene glycol borate. Water amount in ethylene glycol and methanol with water amount in glycerol were found by distillation. Then were prepared boroglycol and boroglycerol. By the amount resulting from the amount of reaction water were observed reaction conditions H3BO3, Na2B4O7•10 H2O and glycerol. At the end was carried out experimental dilution resulting boroglycerol and boroglycol by ethanol, methanol, TMB. Finally, the diluted boroglycerol was deposited on wood. Dehydration of glycerol to acrolein under the catalytic action of KHSO4 was performed. The results are given all the results and discussed the possibility of using the knowledge gained in this work in the industry. In conclusion, there are listed the economic comparison using waste glycerol and crude oil as a raw material and also charts the development of oil prices in 40 years since 1970, and graph of the price of waste glycerol.
|
|
| |
|
|
Nitramide-based energetic materials
Křištof, Adam ; Bednařík, Karel (referee) ; Friedl, Zdeněk (advisor)
Homolytic dissociation of the N-NO2 bond represents primary fission process of energetic materials under the influence of heat, impact, vibration and electric spark. The fission of nitramide bonds is characterized by homolytic bond dissociation energy BDE(RCON-NO2) or disproportionation bond energy DISP(RCON-NO2), which is expressed by an isodesmic reaction RCON-NO2 + SCON-H › RCON-H + SCON NO2, where SCON NO2 is a standard nitramide (1-nitropiperidin-2-on, NPO). This kind of virtual chemical calculation cancels the effect of electron correlation, accompanying the theoretical calculations of free radicals. In this thesis, the homolytic dissociation bond energy BDE(RCON-NO2) and disproportionation bond energy DISP(RCON-NO2) were evaluated for 13 cyclic nitramides using the DFT B3LYP/6-311+G(d,p) method and at the same time the total charges of corresponding nitro groups Q(NO2) were calculated by DFT B3LYP/6-31G(d,p) method. The evaluated BDE and DISP energies were correlated with detonation parameters as squares of detonation velocities and detonation heats. The resulting relationships allow a more detailed description of dependence between the molecular structure of evaluated nitramides and their explosive properties.
|
guest ::
RSS feed.