|
|
PCP sorption of lignite
Šnédarová, Gabriela ; Taraba, Boleslav (referee) ; Pekař, Miloslav (advisor)
Within the framework of this diploma thesis, the sorptive capability of a lignite as a natural adsorbent was applied on an aqueous solution of pentachlorophenol. The aqueous solution of this substance, which is very dangerous for the environment, was prepared in various concentration ranges according to reached solubility. The solubility is noticed in different literatures variously and then is not applicable. That is why it was necessary to find out the ”real“ solubility. The aqueous solution of pentachlorophenol of given concentration was subsequently put to adsorption with exactly defined quantity of the lignite and as a result the adsorptive isotherms were obtained. These isotherms represent the adsorption capability in dependence on the adsorption duration, quantity of used lignite and concentration of pentachlorophenol solution. By the adsorption with duration longer than one hour, the quantity of adsorbed PCP does not increase markedly.
|
|
|
Non-energy uses of lignite
Zedníčková, Petra ; Taraba, Boleslav (referee) ; Pekař, Miloslav (advisor)
This bachelor thesis is focused on the meaning of coal and it's utilize. It is especially concentrated on lignit and it's utilize out of energetic sector. Lignit constitudes geologicly youngest type of coal and belongs to caustobiolits , which is solid with various degree of coalification of original phytomasa. Degree of coalification is situated between peat and lignit. Lignit is characteristic by clearly well-kept structure of wood. Exactly this relative youth of lignit is reason for it's interesting qualitative indexes, in which belongs especially it's natural sorptive ability and quite high volume of humic acids. Both of these characteristics cohere together, because humic substances will certainly be main reason for sorptive characteristics. Coal, in comparing with other natural material, is by it's structure very complicated mixture of both organic and inorganic substances in various states of matter. It is matter of heterogenous system of macromolecules, which is structured of microscopicly distinguishable and chemically various substances. It can be composed of organic components or work as mineral admixture.
|
|
|
Study of the coal oxidation temperature dynamics
Taraba, B. ; Peter, R. ; Slovák, V. ; Janek, Jiří ; Dušková, Anežka
Temperature dependence of coal oxidation rate was investigated between 30°C and 160°C using air flow reactor and/or methods of inverse gas chromatography, pulse flow calorimetry and thermogravimetry. As a parameter quantifying the temperature dynamics of coal oxidation, values of activation energy E were calculated from Arrhenius plots (Ln (oxidation rate) versus Reciprocal temperature). These E values were found to vary between 28 and 57 kJ/mol. Moreover, non-linear course of the Arrhenius plots was confirmed with breaks at temperatures between 45°C and 120°C. The break was denoted as threshold temperature Tth and its value indicates a temperature beyond which the coal oxidation gains more intense disposition. Based on the experimental results, reason of the change in coal oxidation process at the Tth temperature was revealed to be chemical in character.
|
|
| |
guest ::
