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Adjustment of laboratory wastewater containing chromium
Riša, Juraj ; Vomáčková, Alena (referee) ; Pilátová, Ivana (advisor)
The Bachelor Thesis deals with treatment of laboratory waste water containing chrome. It examines the chrome and its compounds in waste water from inorganic laboratory, trying to concentrate it in the waste water. It uses spectrophotometry with diphenylcarbazide as a method to determine concentration of chromium. To diminish the amount of chromium in waste water, precipitation with barium chloride is used prior to regular pressure filtration. Other part of the Thesis focus on the economic effectiveness of the treatment and its comparison to transport of the waste.
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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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Possibilities of utilization of nitrogen compounds from liquid suspensions generated in waste management
Vajdíková, Tereza ; Mergl, Václav (referee) ; Kalivoda, Josef (advisor)
This thesis deals with the removal of ammoniacal nitrogen from biogas plant waste to produce a new usable product. In the theoretical part of the thesis, attention is paid to waste management from the perspective of biogas plants, the problem of nitrogen, and its removal. The thesis contains, among other things, theoretical calculations that include distribution and precipitation curves. The practical part deals with the correctness of these curves, as well as the precipitation of ammonium ions to form ammonium magnesium phosphate and stripping. The practical part includes quantitative and qualitative analyses of the individual components involved in precipitation. Nitrogen removal was performed on the model and real samples.
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Silver separation technique for isotopic measurement in archaeological samples
Venhauerová, Petra ; Trubač, Jakub (advisor) ; Vaněk, Aleš (referee)
Silver isotopes nowadays present a very fast evolving system. One of the field in which this isotopic system is used is archaeology where the silver isotopes are used as a tracer of monetary and power changes between geographical regions. Through statistical analysis of measured data and their comparison with so far published values can be estimated probability of common source area of metal used for coinage. On Celtic coin samples (180-70 BC) provided by the Institute of Archaeology of the CAS, Prague (A. Danielisová) the isotopic composition of silver was measured. Silver was separated from the matrix elements by a method which uses ascorbic acid to precipitate silver. However, the weights of samples commonly used for this method are generally distinctly higher than the amounts of the obtained fragments of Celtic coins. Regarding the differences in the method and low weights of fragments, tests with variable concentrations of ascorbic acid and amounts of silver were performed. The amounts of silver used for this method are commonly ~30x-70x higher. The results showed that this method effectively separates silver from matrix elements and is sufficient for higher concentrations of silver; with lower ones the yields are reduced. The separated silver was measured using MC-ICP-MS. The adjusted...
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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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Zásady používání syřidel při sýření mléka
Lysek, Adam
This Bachelor thesis is concerned with the rennet issue. The aim is to study available scientif-ic literature about rennet's and their usage during the fresh cheese production. The rennet is a complex of enzymes produced in the stomachs of ruminant mammals. Chymosin, it is the component that curdles the casein in milk. The thesis describes the characteristic of rennet, placing them into the basic groups and their effect on milk coagulation. Then the rules of us-ing are described and factors which affect their efficiency. The key factors is structure, quality of milk in terms of salt and fat foreign substances, curdling time, strength and quality of used rennet. The thesis also includes rennet dose calculation and curdling procedure.
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Vlivy působící na aktivitu syřidel při sýření mléka
Lysek, Adam
This thesis examines the issue of rennets. In this work the basic structure of milk is described, then characteristics and rennets division and it´s principle during milk coagulation. Furthermore I have tried to describe factors, which influence thein efficiency and principles during using rennets. This work also includes working proces of milk curdling and dose calculation. In practical part the aktivity of rennet was observed during different storage conditions, influence on yield and quality of curd after 2 minutes dripping. The strength of rennet was fixed, the dose of the rennet needed to curd 1000 l of milk. For the setting was used recombinant milk powder according to IDF requirements. The samples of rennets were tried on the semi-skimmed milk and the whole milk. The four months storage in the fridge has dropped the activity of rennet down 19 % and during laboratory temperature down 27 %. To cut down the activity of rennets has increased the dose of rennet needed for curdling 1000 l of milk and the price of rennet. The most stability was rennet Laktosin, the most degradation rennet Laktochym.
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Silver separation technique for isotopic measurement in archaeological samples
Venhauerová, Petra ; Trubač, Jakub (advisor) ; Vaněk, Aleš (referee)
Silver isotopes nowadays present a very fast evolving system. One of the field in which this isotopic system is used is archaeology where the silver isotopes are used as a tracer of monetary and power changes between geographical regions. Through statistical analysis of measured data and their comparison with so far published values can be estimated probability of common source area of metal used for coinage. On Celtic coin samples (180-70 BC) provided by the Institute of Archaeology of the CAS, Prague (A. Danielisová) the isotopic composition of silver was measured. Silver was separated from the matrix elements by a method which uses ascorbic acid to precipitate silver. However, the weights of samples commonly used for this method are generally distinctly higher than the amounts of the obtained fragments of Celtic coins. Regarding the differences in the method and low weights of fragments, tests with variable concentrations of ascorbic acid and amounts of silver were performed. The amounts of silver used for this method are commonly ~30x-70x higher. The results showed that this method effectively separates silver from matrix elements and is sufficient for higher concentrations of silver; with lower ones the yields are reduced. The separated silver was measured using MC-ICP-MS. The adjusted...
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Evaluation of pH effect on solubility and precipitation of proteins from hemp (\kur{Cannabis sativa} L.) meal
JAROŠOVÁ, Markéta
In this thesis was examined the influence of pH on solubility and precipitation of proteins extracted from the flour of the Cannabis sativa L plant. For this experiment was chosen the pH in the range of 3 to 11. Monoecious breeds of canabis USO 31 and Fedora 17 were chosen for this purpose. Laboratory methods were applied after the protein extraction, in order to define the content of nitrate substances which was the highest at pH 11. Protein spectrums were detected by the SDS-PAGE analysis where especially in an alkaline environment, globuline fraction was present at a greater amount than was the albuminium one. The next step was the isoelectric precipitation of extracted proteins within the variances containing high values of nitrate substances. The content of the nitrate substances in the protein extract was spanning between 56,3 % to 92,9 %. Based on the results of the experiment, is is feasible to conclude that Fedora 17, which was extracted at the alkaline pH 11 and isoelectrically precipitate to pH value 5 and 6, contained the highest amount of protein.
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Adjustment of laboratory wastewater containing chromium
Riša, Juraj ; Vomáčková, Alena (referee) ; Pilátová, Ivana (advisor)
The Bachelor Thesis deals with treatment of laboratory waste water containing chrome. It examines the chrome and its compounds in waste water from inorganic laboratory, trying to concentrate it in the waste water. It uses spectrophotometry with diphenylcarbazide as a method to determine concentration of chromium. To diminish the amount of chromium in waste water, precipitation with barium chloride is used prior to regular pressure filtration. Other part of the Thesis focus on the economic effectiveness of the treatment and its comparison to transport of the waste.
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