čas: 23.4.2021 00:07:48
Obnovit | RAW
Department of Inorganic Technology
List of available PhD theses
Application of microreactors for study of reactions in the field of fine chemicals and pharmaceuticals
Microreactors presents devices with small internal dimensions providing unique features for precise chemical processes control. These features are often employed for continuous processes control in field of fine chemicals and pharmaceuticals, where high product quality is required. Despite the high potential for improvement by synthesis in flow, the batch processes still prevail in industry. This thesis proposal therefore aims at the microreactor technology application, adaptation an optimization for continuous synthesis of fine chemicals and pharmaceutical components. Thecandidateshould have a good knowledge of chemical and reaction engineering, organic and inorganic chemistry and has a good relation to experimental laboratory work to become familiar with microreactor technology, as well as with data acquisition and evaluation systems. To complete the delegated tasks, the personal abilities such as independence, creativity, open mind and team work skills will be required. ---------------------------------------------------------
Catalysts for alkaline energy conversion devices
Alkaline energy conversion technologies represent one of the promising ways to increase the utilization of the installed renewable sources of energy. The advantage of the alkaline technologies lies in the possibility to avoid the necessity of the utilization of the Pt-group metals as catalysts for electrode reactions. On the other hand, the intensity of these technologies is generally lower when compare to alternatives. This work focuses on the synthesis and optimization of the new catalysts, their testing using standard procedures and under the real conditions of the energy conversion devices.
Catalytic transformation of methane to higher value products
The high attention on the processes of transformation of methane (C2, C3 hydrocarbons eventually) from natural gas or biogas to higher value products is paid at present time. The processes such as non-oxidative catalytic methane aromatization, selective oxidation to methanol or dimethyl ether are used. The suitable catalyst for chosen process will be developed. The effect of the reaction conditions, catalyst carrier and formation of active phase on catalyst on the methane conversion, catalyst stability and yield of products will be studied.
Development of the bipolar plates for the PEM type fuel cells
Bipolar plates represent an important part of the fuel cell construction set-up. They contribute significantly also to the fuel cells stack production costs. This is because of corossion aggressiveness of their working environment and related material demands. Target of this project is to develop alternative approach based on utilisation of steel based plates surface modified by suitable composite. Inseparable part of the project is CFD modelling of the reactants and products flow in the flow field geometry targeted to optimise their structure.
Electrochemical methods for process water treatment
Electrochemical methods are suitable for water treatment due its simplicity and high efficiency. Main disadvantage is usually high price. Therefore electrochemical methods are used in the case of water of high salinity or otherwise contaminated. This is not possible to be treated by biochemical methods. Application of individual method has to be evaluated with respect to the direct process water composition.
Electrochemical synthesis of hypervalent iodine compounds as highly selective organic oxidants
A highly selective oxidations of organic compounds belongs, especially in the case of highly added value products, among highly attractive processes. At present, such conversions are usually achieved using oxidation agents based on often toxic transition metals such as Cr(VI), Mn(VII), Ru(VI) či Os(VIII). An interesting „green“ alternatives to these oxidants represent benign hypervalent iodine based organic oxidation agents. The work will be focused on investigation of electrochemical behaviour of these compounds and their precursors. A motivation of the work is to use electrochemical oxidation for the production of hypervalent iodine oxidants allowing their application as industrial scale.
Galvanic electrocatalytic layers in water alkali electrolysis
The aim of this project is development of an efficient electrocatlyst for cathodic hydrogen evolution reaction (HER) in an alkaline environement based on galvanic modification of the Ni substrate. After identification of the optimal coatings properties and deposition method the techniques will be transferred to the 3D porous electrodes to enhance process efficiency and tested in a laboratory and pilot scale alkaline water electrolysis cell.
Investigation of water electrolysis with proton exchange membrane
Water electrolysis represents an important part of the hydrogen economy considered nowadays as a promising approach to the future securing of the human society with electrical energy. Industrial water electrolysis processes established today suffer from several disadvantages when considering its application in the field of energetics. It is mainly its low efficiency and flexibility. Therefore, this process is a subject of interest of numerous research laboratories around the globe. Electrode reaction kinetics, suitable polymer electrolytes and overall process design represent the main issues studied. Corrosion stability of the individual construction materials is also an issue.
Kinetics of catalytic decomposition of N2O on zeolite catalysts
The topic of this work is the study of kinetics of N2O decomposition on zeolitic (MFI, FER) and titano-silicates catalysts involving Fe and other transition metals. The work will be focused on kinetic experiments in aiming to develop reliable kinetic model suitable for desing of industrial equipment.
Mathematical modelling of chemical and membrane processes using universal simulation programs
Universal simulation programs introduce a tool suitable for design of new and optimization of existing industrial technologies. In the frame of this work the static and dynamic models of selected advanced membrane and/or chemical technologies or their parts will be developed using universal simulation programs. By the help of them and computer experiment the behavior of these technologies will be studied. Verification of developed models by experimental data will be implemented. Aim of the work is the improvement of economic and ecological technological parameters. The universal simulation programs from Aspen Technology will be used preferentially.
Nanostructured/ composite materials based on TiO2 for photocatalytic processes in gaseous phase
Air polution represents a significant problem which can be conveniently solved by an application of photocatalytic processes. Therefore the aim of the present thesis is the preparation of new photocatalytically active composite materials based on TiO2 and the determination of their adsorption and photocatalytic properties. Titanium dioxide nanotubes prepared by anodic oxidation show a larger active area (compared to planar samples), allowing more efficient removal of polutants from the gaseous phase. The influence of various modifications of TiO2 nanotubes and of operating parameters (flow, humidity and UV intensity) on photocatalytic efficiency will be investigated. The goal is to get the material having at the same time good adsorption properties and at the same time a high ability to remove unwanted volatile substances in the air. Part of the work will use the standard ISO tests for monitoring the kinetics of oxidation reactions (NOx, VOCs) on the surface of the prepared photocatalysts. The important part is the characterization of materials/coatings (XRD, SEM, BET, Raman spectroscopy) and further development of methods allowing the testing of functional properties of the prepared materials/coatings in air treatment.
Optimization of Electrochemical Ferrates(VI) Synthesis
The aim of this project is characterization of chemical and electrochemical oxidation processes taking place at the surface of an anode made of iron based materials in strongly alkaline solutions. Deeper understanding of mechanism of these processes allows to enhance efficiency of synthesis of Ferrate (VI) making it economically viable.
Photoelectrochemical systems for conversion of solar light
A photoelectric chemical system involving a photoanode, photocathode, membrane and suitable ox/red couple allows the conversion of solar energy into chemical energy. The theme of this thesis is the investigation of possible systems for solar energy conversion with a focus on suitable photoanode and photocathode materials and their combination with suitable electrolytes. Part of the work will be the preparation of selected photoanode or photocathode materials (e.g. Fe2O3, ZnO, WO3, BiVO4, CuO, CuFeO2, etc.) and investigation of their behaviour during long-term photoelectric polarization.
Different methods of preparation (aerosol pyrolysis, spray pyrolysis, etc. ) will be used and the resulting films will be characterised (XRD, GDS, UV-VIS, BET, SEM) and their photo-electrochemical properties (open circuit potential, photocurrent, IPCE) evaluated. The attention will be given to the influence of composition, doping, crystalline phase, layer thickness and porosity.
Photoelectrodes for pollutant removal and hydrogen generation from water using solar light
Production of hydrogen as an alternative energy source/carrier is becoming recently very important and intensively studied process. One of the promising options is direct production of hydrogen from water via solar light. Very important process is also removal of persistent pollutants in waters by advanced oxidation processes, one of them is photo-electrochemical oxidation. The topic of the present thesis is the preparation of semiconductor photoanodes and photocathodes (eg. WO3, BiVO4, CuO, CuFeO2, atd.) for photo-electrochemical water splitting or photo-electrochemical removal of persistent pollutants. Different methods of preparation (aerosol pyrolysis, spray pyrolysis, etc. ) will be used and the resulting films will be characterised (XRD, GDS, UV-VIS, BET, SEM) and their photo-electrochemical properties (open circuit potential, photocurrent, IPCE) evaluated. The attention will be given to the influence of composition, crystalline phase, layer thickness and porosity. The best photoanode and photocathode layers will be applied in the tandem solar photo-electrochemical cell and its efficiency for water decomposition to hydrogen and oxygen by sunlight will be determined.
Polymer electrolytes for energy conversion devices
Polymer ion selective materials are well established in the many technologies including the environment protection, food industry and large scale production of the basic chemical substances. Energy conversion devices represent the recent but sharply growing field of the ion selective membrane utilization. The work is focused on the complex characterisation of the physio-chemical and electrochemical properties of the developmental ion selective polymer electrolytes.
Preparation and characterization of mixed matrix membranes for gas separation
Gas membrane separation represents one of the perspective and energy saving alternative with respect to the present separation processes (PSA, TSA etc.). In the frame of this work the mixed matrix membranes, combining the perspective properties of the both, microporous and polymeric membranes, will be prepared and characterized. The microporous material e.g. ZIF-8, silicalite-1, ETS, FAU, TS-1, AFX, MOF will be used as filler and combined with polyimide matrix. The key issue of mixed matrix membranes preparation which needs to be solved is the adhesion and interface interactions of filler and polymer because of their effects on compactness and selectivity of membrane. The aim of this study is evaluation of different possibilities of microporous and polymer phase modifications with respect to the compactness of membranes and their selectivity and permeability in selected systems of hydrocarbons, CO2 and H2.
Rational design of oxides for anodic electrolytic reactions
The work will focus systematically approach to description activity and selectivity of oxide materials in gas evolving anodic processes namely in oxygen and chlorine evolution. Primary attention will be paid to the behavior of modelf binary in the systems based on Ru-Ti-Me (Me= transition metal) identified as prospective materials in computational studies. General relationships between the local structure of the active sites on oxides and their activity in electrocatalytic processes will be formulated and subsequently used in formulation of novel class of anodic electrocalytst.
Self-cleaning and antibacterial coating based on TiO2 and ZnO
The main scope of this work is preparation of photocatalytic active coatings/ paints based on TiO2 a ZnO on the appropriate substrate (ceramics, glass, metals, facades, hydraulic binders) by different methods. The important part of the work is films characterization (XRD, SEM, Raman spectroscopy) and development of methods for testing photoactivity and hydrophilic and antibacterial properties of prepared layers. Studied parameters will be the methods of precursor deposition (dip-coating, spraying) and the influence of the binder in the coating and the substrate.
Separation of humic substances from water by membrane processes
Study of inorganic ions separation by nanofiltration
Titanium oxides and titanates for advanced applications
Li-ion batteries are one of the most promising electrochemical power sources. Ti-based materials such as Li4Ti5O12, Li2Ti3O7, TiO2-B and H2Ti3O7, are considered as important anodes for Li-ion batteries due to their high safety and excellent cycling stability. Li-ion battery (LIB) technology (typically using carbon materials as the anode) faces serious challenges if it is to take over the hybrid electric vehicles and stationary power sources. Ti-based compounds, especially Li4Ti5O12 have been demonstrated as the most promising anode materials for large-sized LIBs since they exhibit excellent cycling reversibility and a high operating voltage to ensure improved safety. However, the rate capability of these Ti-based materials are relatively low because of a large polarization at high charge–discharge rates. To enhance its electrical conductivity, ion doping and surface modification, and ionic diffusivity by designing various nanosized materials were used. A new preparation method will be used based on the extraction of sulphate ions from the crystals of titanium sulphate hydrates and their replacement with hydroxyl groups in aqueous alkali solution. The method leads to nanostructured metatitanic acid or alkali titanates and is suitable also for metal doping the material.