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Pressure loss of catalyst carriers
Linda, Matúš ; Kilkovský, Bohuslav (referee) ; Jecha, David (advisor)
The diploma thesis is divided into four main parts. The first part deals with the issue of waste management and its energy utilization in waste incineration. Processed harmful substances produced by incineration as well as emission limits. It deals with the types of catalytic carriers, their description, production and more detailed processing of ceramic foam VUKOPOR. The second part is devoted to technologies utilizing catalytic processes and a more detailed specification of the process. In the third part there is processed the calculation methods for pressure losses for individual types of carriers. Fourth, the most extensive part describes the INTEQII experimental device, its technology and construction, as well as the principle of the practical part, measuring of the pressure losses of carriers. It includes the evaluation of pressure losses in separate categories of carriers, such as the bed, HoneyComb and VUKOPOR ceramic foam. Subsequently, a comparison of the pressure losses of all carriers is made relative to the reference size of 1 m. The impact of bonding of VUKOPOR foam samples on the size of pressure losses is discussed. At the end of this section, the suitability of calculation methods for individual carriers is evaluated, depending on the experimental pressure loss data.
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Equipment for Disposal of Waste Gases of Catalytic Oxidation
Brummer, Vladimír ; Martinec, Jan (referee) ; Leštinský, Pavel (referee) ; Bébar, Ladislav (advisor)
This thesis deals with the design of the equipment and documentation for the design of equipment for the removal of volatile organic compounds (VOC) and carbon monoxide (CO) by catalytic oxidation and the selection of appropriate technological conditions for this technology. Introduction is devoted to familiarization with the field of the catalytic oxidation, used catalysts, catalyst supports and their active components. Advantages and disadvantages of the use of catalytic oxidation versus thermal incineration are outlined and currently applicable legislative terms for VOC and CO emissions are listed. In the next part of the thesis the fundamental mathematical tools and research findings available for catalytic reactor model designed primarily for monolithic catalysts are summarized. Presented kinetic model considers continuous reactor with plug flow of gas and adiabatic heating by oxidation reactions corrected for the heat loss of the reactor. The next chapter discusses the design of the new prototype of the catalytic oxidation pilot plant (i.e. the reactor incl. peripherals) primarily intended for monolithic catalysts and bulk catalysts in the form of the fixed bed. The basis for the design and sizing are material and energy balances in the ChemCAD for different intended use of the unit, from which boundary conditions of the unit operating parameters arises. Pilot plant has been designed and built, functionality tests was scheduled also with consecutive obtaining of experimental data not only for the reactor kinetic model. Results of the model for the catalytic combustion were in good agreement with measured data. The next part includes two industrial case studies of the catalytic oxidation process usage for the chemical industry. In particular it was dealt with a replacement of the non-catalytic combustion for the catalytic for VOC abatement from chemical production plants off-gas streams of the company Momentive Specialty Chemicals in Sokolov and German city Leuna. These case studies have brought many valuable experimental and technological knowledge from long-term pilot tests and also verification of design concept, thanks to which it was later possible to design a pilot unit for removal of pollutants in premises of NETME Centre and among other to economically evaluate the usage of catalytic oxidation for the off gas cleaning, in comparison with traditional combustion, in two completely different individual cases. This information was valuable and necessary for the verification of theoretical assumptions of the thesis on specific conditions of two different industrial productions. Based on acquired practical experience and theoretical background, guidelines for designing of devices for VOC and CO removal in the industry were developed.
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Catalytic synthesis of polyanilines
Bláha, Michal ; Vohlídal, Jiří (advisor) ; Omastová, Mária (referee) ; Trchová, Miroslava (referee)
This Ph.D. thesis is dealing with catalytic polymerization of aniline (ANI) and partially also of substituted anilines with FeCl3/H2O2 catalyst system, in which according to obtained results both active species, Fe3+ and HO , participate in the overall polymerization mechanism, creating a synergic system. The Fe3+ /H2O2 catalyst system, also called Fenton's system can considerably lower contamination of forming neat polyanilines (PANIs) by side-products characteristic of stoichiometric polymerization. However, catalytically prepared PANIs exhibit reduced conductivity related most probably to side reactions involving radicals generated as integral components of the FeCl3/H2O2 system. Catalytic polymerization of ANI with FeCl3/H2O2 system was found to be the reaction of approx. 2nd order with respect to ANI and gives PANIs of a good quality only when [H2O2] in the reaction mixture was kept low, i.e., at under- stoichiometric ratios [H2O2]/[ANI]. At over-stoichiometric ratio [H2O2]/[ANI], PANIs of lowered conductivity, worse spectroscopic characteristics and increased size of PANI nanostructures were obtained; nevertheless, these PANIs were not over-oxidized to pernigraniline state. The reaction-time profiles of the open-circuit potential of reaction mixtures exhibited an inflection related to the...
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Catalytic oxidation of VOC on commercially available catalysts
Osička, Tomáš ; Jecha, David (referee) ; Brummer, Vladimír (advisor)
The main topic of this thesis is a catalytic oxidation which belongs to a group of modern technologies for removing emission of CO and VOC from waste air. In the introduction of this thesis, the basic concepts are defined. Further the legislative requirements associated with VOC emissions, emission limits and conditions are summarized. Described destructive and non-destructive methods for removing VOCs from waste gases are also briefly described. Increased attention is paid to the catalytic oxidation as the main theme of the thesis. It was searched for industrial applications where the catalytic oxidation is used. Another chapter is devoted to the theoretical analysis of kinetics of catalytic oxidation reactions. Firstly, the basic types of reactors are described and also material balance and reaction rate for the isothermal and adiabatic reactor. In the experimental part results of performed kinetic measurements on a pilot unit for catalytic commonly used organic solvents (VOCs) using commercially available catalysts were summarized. Pre-exponential factors and activation energies for sprinkling catalysts EnviCat VOC-5565 and EnviCat 55068 for substances ethanol, toluene and acetone were determined. "Light-off" curves for these substances and methane were measured and on sprinkled catalyst EnviCat 55068 and on monolithic catalyst Purelyst PH-304.
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Treatment of waste gases polluted by freons
Frydrych, Tomáš ; Houdková, Lucie (referee) ; Dvořák, Radek (advisor)
This thesis inquire into experimental decomposition of freon R-22 (CHClF2 - chlorodifluorometan) for different process conditions, by the help of pilot experimental unit in heavy laboratories DEPARTMENT of process and enviromental engineering Brno. This unit can decomposition waste gas, as the case may be combustion gas by the thermic oxidation or catalytic oxidation. Ground was in theoretical research, in which had been executed decomposition of freon R-22 in laboratory. In terms of experimental work were to be execution states for decomposition of freon R-22, next will be decomposition of freon R-22 by catalytic oxidation on catalyst Pt/Al2O3 and consequently this experiment will be analyse. Part of this thesis is exploration of facts basic way to decomposition of freon R-22, accounting of experimental unit and discussion of results.
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TiO2 pillared clay for photocatalytic purposes
Fiala, Michal ; Šoukal, František (referee) ; Ptáček, Petr (advisor)
Bachelor’s thesis describes preparation of mixed catalytic systems kaolin/ TiO2 and metakaolin/ TiO2. Samples were prepared via hydrolysis of TiCl4 in kaolin suspension. Catalyst metakaolin/ TiO2 was prepared by calcination of this material under static oven atmosphere at 600 °C. Thermal analysis (simultaneous TG-DTA), infrared spectroscopy (FT-IR) and electron microscopy (REM) were used for samples characterization. Catalytic efficiency of mixture kaolin (Sedlec Ia) or metakaolin with TiO2 (anatase) was compared with pure kaolin. Experiment is based on oxidation of ethylalcohol, which was introduced in to reactor in flow of inert gas (argon). Amount of decomposed ethylalcohol is proportion to concentration of oxygen in gas product outputting from reactor. System kaolin/ TiO2 show higher catalytic performance than metakaolin/ TiO2 catalyst.
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Oxidation of Volatile Organic Compounds in a Multifunctional High Temperature and High-Pressure Cassette Microreactor
Vajglová, Zuzana ; Stavárek, Petr ; Křišťál, Jiří ; Jirátová, Květa ; Ludvíková, Jana ; Jiřičný, Vladimír
Analysis of the total oxidation of ethanol including reaction intermediates data obtained in the examined reactors on the temperature showed that differentmaterial applied in the construction of reactors and their arrangement give slightly different results of catalyst testing, the ones obtained from microreactor being more precise. More precise control of reaction temperature due to higher heat transfer capabilities and limited backmixing of reaction mixture in a packed bed microreactor is advantageous and leads to the more accurate results of oxidation catalysts testing. However, it is necessary to ensure in order the material used for the reactor construction did not affect the catalytic reaction. The results accomplished confirm that microreactors are not only suitable for performing of catalytic reactions in a laboratory scale but also promising way for creation of new, safer and cleaner production processes.
Fulltext: content.csg -  PDF
Plný tet: SKMBT_C22014050212452 - PDF
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