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Chemical and Process Engineering
Doctoral Programme,
Faculty of Chemical Engineering
--- Careers--- Programme Details
Ph.D. topics for study year 2025/26CO2 capture. Industrial process optimization.
AnnotationCO2 capture belongs to frequent industrial needs, both in the cases of low concentration CO2 removal from waste gases and in the cases of main process streams, e.g., in hydrogen production, when high amount/concentration is to be removed. Just the last example represents the process, which the PhD thesis will be focused to. In the premises of Unipetrol company, the CO2 capture unit is presumed to be permanently optimized. In accordance with the needs of the industrial partner, the experimental research goals will involve i) durability / degradability of the solution currently used in the process, ii)absorption efficiencies and selectivities (H2S/CO2) of new absorbents and iii)the influence of low concentration admixtures, e.g., Fe, Ni and V metals, on the CO2 capture efficiency. The PhD student will acquire valuable experience of industrial area life because he/she will be able independently act in the Unipetrol premises, will cooperate with industrial research department UniCRE and will find here both well-equipped laboratories and experienced consultants. The studet's scholarship will be supplemented through the funds obtained by industrial cooperation as the contract with Unipetrol co. (No. 2362 409 004) is. Particle agglomeration and fouling in liquid- and gas-dispersion polymerization reactors
AnnotationAgglomeration and fouling of particles are the undesired phenomena in many polymerization reactors, e.g., in emulsion, suspension, slurry and gas-dispersion processes. These undesired phenomena negatively affect the quality of products and can even cause shut-down of polymerization processes due to fouling of heat transfer surfaces and loss of fluidization. This PhD thesis will focus primarily on catalytic polymerization of olefins in liquid-dispersion (slurry) and gas-dispersion (fluidized or stirred-bed) reactors. Qualitative theoretical explanation of phenomena causing or affecting the agglomeration/fouling is available, but this explanation is scattered in various branches of science. Therefore the first goal of PhD thesis will be the systematic organization of physico-chemical picture involving particle-particle, particle-wall and particle-fluid interactions. The considered description will involve van der Waals interactions, chain entanglement dynamics, effect of swelling on elastic modulus and particle collision dynamics, electrostatic charging of particles, osmotic stabilization of dispersions, lubrication forces, turbulent mixing conditions, effect of particle size distribution and particle surface texture, heat transfer effect, liquid bridges and thermodynamics of species sorption. For the quantitative understanding of agglomeration and fouling processes, we need the conduct series of well-designed systematic experiments aiming at: (i) measuring the dynamics of agglomeration / fouling in reactors, (ii) characterization of particle and dispersion mixture properties, and (iii) characterization of particle-particle, particle-wall and particle-fluid interactions. In this respect, the laboratory is equipped with all the required equipment involving mixed reactor, AFM, micro-CT, DSC, TD-NMR, rheometry, sorption/diffusion/swelling measurements, digital image processing etc. This PhD project is primary experimental, but the student will conduct also limited DEM (discrete element method) modeling enabling the testing of various hypotheses. The outcomes of PhD thesis will have a broad impact both to fundamental science (experimental studies and systematic data are scarce) and to practical applications (mitigation strategies suppressing unwanted phenomena in agglomeration and fouling). Prospective PhD student is expected to spend a term in some European laboratory with similar research interests and to take some responsibility for the contractual industrial research. Info: phone 220 44 3296, office B-145, e-mailjkk@vscht.cz, webhttp://kosekgroup.cz Particle informatics
AnnotationDrug substances are typically produced in the form of crystals. However, the properties of these crystals can vary dramatically when considering various polymorphs or multicomponent drug solid forms (i.e., salts or cocrystals). The goal of this project is to characterize the surface properties of the drug crystals utilizing the crystal structure. As a part of the project, the student will be involved in the preparation of drug solid forms of interest and their characterization using single-crystal XRD, followed by the solution of the crystal structure. The obtained information will be used to predict properties of the crystal surface in terms of molecules present on the surface, hydrophobicity/hydrophilicity of the surface, intermolecular interactions between molecules located on the crystal surface and to correlate these data with the properties of produced crystals (e.g., stability under elevated temperature or humidity, solubility or dissolution). Furthermore, we would extend the information about the crystal structure to the prediction of crystal-crystal interaction and their relation to the crystal flowability or prediction of bulk properties of crystals (e.g., hardness) and its relation to powder tabletability Diagnostics of two-phase flows in microchannels
AnnotationThe aim of this project is to experimentally investigate the character of two-phase (gas/liquid) flow in microchannels. The mapping of different flow regimes will be performed for different microchannel configurations (e.g., channel crossing, T-junction, sudden expansion) and different model fluids (Newtonian, viscoelastic, pseudoplastic). The electrodiffusion method, an original experimental technique developed in our department, is used to determine the liquid flow in the near-wall region and to detect the characteristics of translating bubbles. The visualization experiments with a high-speed camera and the velocity field measurements with the mPIV technique will provide additional information about the flow structure in microchannels. The candidate should have a Master's degree in chemical engineering or a similar applied science field. He/she should have experimental skills for laboratory work and some basic knowledge of hydrodynamics. However, enthusiasm for independent scientific work is the most important requirement. The candidate will certainly benefit from our long experience in experimental (computer-controlled measurements with subsequent data processing in LabView) and theoretical (solving complex hydrodynamic problems in MatLab or Mathematica) fluid mechanics. Mixing dynamics and its effect on heat transport in granular materials
AnnotationThe PhD project focuses on the study of heat transport in granular systems during the mixing process. Its goal is to analyze the transport mechanisms in granular materials using numerical simulations and experiments. The combination of the Discrete Element Method (DEM), Computational Fluid Dynamics (CFD), and experimental validation provides a comprehensive insight into the system's thermal behavior. The research emphasizes the influence of mixing rotational speed, mixing intensity, and material properties on temperature changes and investigates the role of mechanical forces in heat transport. The results will contribute to a better understanding of transport processes in granular materials and may have implications for materials engineering, chemical industry, and energy systems. Required education and skills • Master's degree in chemical engineering, mathematical modeling, and computer science; • high motivation, willingness to learn new things; • team spirit. Photocatalysed Processes in Microreactor Systems
AnnotationPhotocatalysis offers efficient synthetic pathways and broad substrate diversity, making it particularly valuable for late-stage drug discovery modifications. This research will focus on designing and developing multiphase microfluidic photoreactors for oxidation reactions, emphasizing the transition from batch to flow systems to enhance photon utilization and overall efficiency. The study will investigate interactions between gas (O₂), liquid (reaction mixture), solid (photocatalyst), and light (photons), exploring how reactor geometry, static mixers, and segmented flow influence mass transfer. Applications include fine chemical synthesis, leveraging microfluidic technology to improve reaction efficiency and selectivity. Fractionation and degradative solvent-based polymer/textile recycling
AnnotationThe objective of this PhD project is to generate fundamental knowledge and validated tools capable to immediately aid in the design of solvent-based recycling unit operations, their optimization and scale-up, screening of solvents and their regeneration. Solvent-based recycling can contribute to generating recycled plastics comparable in their performance to freshly synthesized polymers. Particularly, this project will focus on three subjects: The first one is going to be the fractionation of polymers and composite polymers to fractions having different molecular weights or composition. This subject will be the combination of experimental research guided by advanced thermodynamic models. The second subject will be the fundamental research of transport phenomena related to solvent-based polymer recycling, e.g., degassing of volatile components from polymer melts, rheology of polymer solutions and dispersions and swelling/deswelling. Moreover, practical techniques for enhancing transport processes will be explored including ultrasound micro-mixing, RF-heating, high-shear flow separations etc. The third focus will involve degradative recycling of polymer and textiles either by solvolysis, or electrochemical depolymerization at mild conditions (low temperature, moderate pH, etc.). PhD student is expected to be involved in projects of applied and fundamental research and in bilateral collaborations with industry related to PhD project. Moreover, the stay at foreign academic institution (e.g., in Austria) is anticipated. Contact information: Juraj.Kosek@vscht.cz , Dept. of Chem. Engineering, UCT Prague. Physiologically based pharmacokinetic modelling of drug release from long-acting injectable formulations
AnnotationInjectable depot formulations represent a rapidly emerging class of drug delivery systems that offer convenience for the patients, good adherence to medication, avoidance of side effects such as gastric irritation, and theoretically 100% bioavailability. Depot systems often have the form of a suspension of drug of prodrug particles in an aqueous vehicle that also includes stabilisers, viscosity modifiers, tonicity agents and other components. The drug release from intramuscular depots is a non-trivial process that includes particle surface dissolution, diffusion within the depot and the surrounding tissue, enzymatic conversion of the prodrug to the parental drug, absorption into systemic circulation, and eventually biodistribution and elimination from the body. There is an acute need for robust and physiologically relevant mathematical models of drug release from depot systems to enable rational formulation decisions such the effect of particle size distribution or the overall applied dose on the time-dependence of drug plasma concentration in the patient. The aim of this project is to develop, validate and apply such models in collaboration with an industrial partner. Deep eutectic solvents for synthesis and separation of enantiomers
AnnotationDeep eutectic solvents (DESs) are composed of biodegradable and non-toxic chemicals, such as choline chloride in combination with glycerol or urea. These solvents present a promising way for the sustainable production of pharmaceuticals, enantiomers, and other specialty chemicals. DESs serve as versatile reaction media, enabling enantioselective enzymatic reactions, and are also effective as extraction solvents for the separation of chiral alcohols in non-aqueous systems. The primary objectives of the proposed project include: (i) Screening and identification of DESs for the selective separation of chiral alcohols from reaction mixtures. (ii) Development of microfluidic and millifluidic platforms for the synthesis and separation of chiral alcohols and other chiral compounds. (iii) Optimization of DES formulations and device design to achieve high-purity products in a continuous processing regime. Our laboratory is fully equipped to support experimental research in this area. The selected PhD student will actively contribute to grant-funded projects and is expected to participate in international scientific conferences to present research findings. Inhalational drug nanocrystals for systemic delivery
AnnotationThis PhD project will focus on the design, preparation, and optimization of an aerosol drug nanocrystal fabrication process as a promising strategy for systemic delivery of poorly soluble low molecular weight drugs via the inhalation route. With a primary focus on nanocrystal preparation and aerosolization, the research aims to develop efficient techniques for the production of inhalable drug nanocrystals. The study will investigate different methods of nanocrystal preparation (wet milling, continuous precipitation) and evaluate their effectiveness in producing stable monodisperse nanocrystals that allow for better drug dissolution and thus higher bioavailability. In addition, the research will focus on the development and validation of aerosolization devices to ensure optimal drug delivery of nanocrystals. Through this research, the thesis aims to contribute to the development of non-invasive drug delivery methods, which will ultimately facilitate the introduction of new therapeutic agents into clinical practice. The student will learn techniques for the preparation and characterization of nanocrystals, the preparation and characterization of aerosols, and other methods necessary for the research project. In addition, the student will have the opportunity to collaborate within a multidisciplinary research team and present and publish their research. Interactions of bubbles and droplets with vortex structures in liquids
AnnotationBubbles or droplets dispersed in a liquid are essential components of multiphase systems, which are commonly found in processes such as aeration, emulsification, or extraction. Understanding how these fluid particles interact with vortex structures is crucial for optimizing multiphase systems on an industrial scale. This dissertation focuses on numerical simulations of the interactions between fluid particles and defined vortices using advanced CFD methods. The project aims to develop models capable of predicting the dynamics and outcomes of these interactions, including the deformation of fluid particles, their potential fragmentation, vortex deformation, and changes in its energy characteristics. The research combines numerical simulations with experimental validation to provide a comprehensive perspective on the bubble/droplet vortex interface. The results could significantly contribute to the optimization of processes in the chemical, food, and energy industries. Required education and skills • Master's degree in chemical engineering, mathematical modeling, and computer science; • high motivation, willingness to learn new things; • team spirit. Continuous Flow Processes for Sustainable Pharmaceutical Production
AnnotationThis research focuses on developing continuous flow processes to make pharmaceutical production more sustainable and efficient. Continuous processing provides precise control, real-time monitoring, and reduced waste compared to traditional batch methods. A critical component of this approach is continuous flow filtration, which enables seamless solid-liquid separations during production. However, implementing continuous filtration poses challenges, such as managing clogging, scaling up filtration systems for high-throughput operations, and maintaining consistent separation efficiency for diverse pharmaceutical products. Advanced filtration materials and methods will be explored to overcome these issues and enhance both process efficiency and product purity. The research will optimize reaction and filtration parameters, emphasizing the use of green solvents and catalysts to adhere to green chemistry principles. By addressing these technical challenges, the project will demonstrate how continuous processes can significantly lower the environmental impact of pharmaceutical manufacturing while ensuring high-quality production. Ultimately, this work aims to advance sustainable practices and provide scalable solutions for the pharmaceutical industry. Remotely controlled gated magnetic nanoadsorbents
AnnotationAdsorbents are porous materials with a high internal surface that are capable of reversible and selective accumulation of solutes in their pores. Adsorbents are typically used for industrial separation or purification processes, but they can also be applied as sensors to accumulate an analyte, or as drug delivery systems to release a previously loaded bioactive substance. One limitation of adsorbents is that being based on weak non-covalent interactions, the solutes can spontaneously desorb when the adsorbent passes through an environment with lower bulk concertation of the solute, or when competing solutes are present. The aim of this project is to develop adsorbents coated by a phospholipid membrane that will act as a gating mechanism to allow temperature controlled ON/OFF diffusion depending on the phase transition of the lipid bilayer. To enable manipulation with such adsorbents, they will also contain magnetic nanoparticles, which can simultaneously act as susceptors for radiofrequency heating. Thus, solute accumulation or release from the adsorbents can be temporally and spatially controlled from a remote source. Such nano-devices will be used for collecting solutes from complex microenvironments such as biological tissues of biofilms, and for drug delivery and controlled release to such environments. Mathematical modelling of electrochemical processes
AnnotationTéma je zaměřeno na vývoj pokročilých matematických modelů pro deterministický popis elektrochemických dějů. Jednou ze studovaných oblastí budou iontově-výměnné membrány, jež hrají ústřední roli v mnoha významných technologiích jako např. v elektrodialýze, palivových článcích či bateriích. Teoretický popis dějů probíhajících na straně elektrolytu v blízkosti povrchu membrány vyžaduje prostorově rozlišený matematický model spojující transport iontů elektromigrací (Nernstova-Planckova rovnice), lokální rozložení elektrostatického potenciálu (Poissonova rovnice) a proudění elektrolytu (Navierovy-Stokesovy rovnice). Predikce získané vyvinutými modely budou validovány dostupnými experimentálními daty a umožní hlubší pochopení dějů probíhajících v elektrochemických systémech a tím jejich optimalizaci a vylepšený design. Téma bude finančně podpořeno z projektu GAČR č.25-18111S, jehož hlavním řešitelem je doc. Zdeněk Slouka, školitel-specialista této práce. Mathematical modeling of continuous-flow bioreactors and bioseparators
AnnotationMicrofluidic devices are characterized by a large surface-to-volume ratio. This can be used in the efficient separation of special chemicals using extraction, membrane and other processes. The separation of optically active substances, important pharmaceutical products or circular economy intermediates is a challenge for contemporary chemical engineering. Mathematical modeling can lead to a better understanding of the complex reaction-transport phenomena in such devices and to the design of efficiently operating microfluidic reactors and separators. The main goals of the proposed PhD project are: description of the kinetics of reactions catalyzed by free and/or immobilized enzymes in microreactors, development of a mathematical-physical description of mass and momentum transport in microseparators with an imposed electric and/or magnetic field, optimization of modular microreactors-separators in order to achieve a high degree of conversion and high separation efficiencies. The models will be studied using approximate analytical techniques and numerically using the COMSOL program. Our laboratory is equipped with powerfull workstations and PCs. It is assumed that the doctoral student will be involved in grant projects and active participate at international scientific conferences. Membrane separation of fermentation primary products
AnnotationIn biotechnologies, batch processes are often used, in which living cultures/biomass are used. Metabolites produced by culture are often poisonous and can damage the culture itself, as an example of which can serve ethanol fermentation. In periodic processes, the initial periods including sterilizing, nutrient dosing, etc., used to be time consuming, financially burdening. Therefore, it is desirable to dedicate an effort to develope continuous performance of such processes. One of the operations ensuring the process continualization can be membrane separation. This case brings the necessity of two membranes modules: i) microfiltration to separate solid particles-biomass and ii) pervaporation to separate primary product of fermentation, e.g., ethanol, as mentioned above. The goal of this work is to experimentally develop two step membarne separation technique, including microfiltration and pervaporation, to be prepared for an interconnection with a fermenter. THe development will be conducted from the viewpoint of chemical engineering. The reached separation parameters (selectivity, permeability) will be investigated in dependency on the process parameters (pressure, flowrate, temperature, feed composition). Chemical engineering quantities (membrain polarization module, mass transfer coefficient,...) will be used to describe these dependencies. At the workplace the new membrane modules are available, which were purchased for the purpose of this development. The PhD student will get familier both with industrial membrane module and with the custom made one. In addition to being familiar with modern technologies introduced in industry, the PhD student will also work in the team of students and academic staff who are experienced in industrial cooperation. PhD study will prepare the student to obtain either qualified working position in industry or to be able systematically conduct further research from the viewpoint of qualified chemical engineer. Further information Assoc. Prof. Tomáš Moucha, UCT Prague, building B, room T02, email: tomas.mooucha@vscht.cz. Student's scholarship, according to the law valid from September 2025, will be supplemented by the research group's financial resources obtained through industrial collaboration, and by the resources by The Czech Science Foundation, when the project granted from January 2026. Minimizing energy consumption in bakery production
AnnotationThe production of pastries (specifically the baking phase) is an energy-intensive process, in the management of which empirical experience gained over many decades also plays a significant role. The main criterion is the acquisition of optimal taste and appearance properties of the product. Minimizing energy costs has not yet received much attention in the field of pastry production. In times of significant increases in energy prices, it is therefore highly desirable that the issue of energy costs of baking be addressed more intensively. Within the framework of the offered dissertation, activities aimed at the following goals will be conducted. 1. Temperature profiles optimization for various industrial oven types aiming to the production of bread and pastries remaining optimal organoleptic parameters and minimum of process contaminants. Simultaneously, the energy consumption will be minimized, including energy losses during the products cooling. 2. General mathematical model development and the optimization methodology for direct use by bakery technologists. Based both on the experimental data and on mathematical modelling results, the methodology to design effective baking regime will be developed. 3. Software development for baking process optimization, which aims to the formation of intuitive, easy use and robust, industrially verified software usable by industrial technologists The work will be financially supported within the framework of the NAZV project and will be performed in cooperation with the Department of Carbohydrates and Cereals at UCT Prague. According to the law valid from September 2025, the studet's scholarship will be supplemented through the funds granted in the project QL24010110. Modelling of fluid flow during processing of colloidal suspensions
AnnotationColloidal stability of suspensions (polymeric nanoparticles or proteins) is related to environmental parameters such as ionic strength, amount of surface-active agents, or level of shear rate. Furthermore, the presence of another phase of liquid or gas can negatively affect the stability of suspended particles. The flow field will be characterized by computational fluid dynamic (CFD) simulations of single and multiphase flow in stirred vessels with various impeller shapes typically used for aggregation of polymer nanoparticle suspensions or precipitation of proteins. The student will be involved in the buildup of computational mesh and simulation of flow (single phase or multiphase) using various approaches (Euler-Euler and Euler-Lagrange). Mesh independent results of fluid flow characteristics (i.e., maximal hydrodynamic stress, duration of high-stress exposure, mixing time) will be correlated with experimental data of aggregation/gelation time. For selected cases, the modelling of the aggregation process of suspended particles will also be implemented in the CFD. Bioreactors Design Parameters - Experimental study of transport characteristics in various apparatuses
AnnotationThe efficiency of new biotechnology and pharmaceutical products manufacture also depends on a suitable bioreactor selection. In the design of an optimal bioreactor, they key parameters are the maximum yield of a primary product and, simultaneously, the lifetime of the used microorganisms. The aim of the doctoral study is to compare the design parameters (transport characteristics such as volumetric mass transfer coefficient, gas hold-up and energy dissipation intensity) of three types of the most commonly used bioreactors. The results will be used to characterize the differences and similarities of specific types of bioreactors in terms of gas distribution, mass transfer and mixing depending on the total energy supplied to the system. Transport characteristics will be obtained experimentally for model batches, which will be designed based on physical properties of real broths. The work is intended as the cooperation of UCT Prague (supervisor's workplace) with ICPF Prague (consultant's workplace) and appropriatley complements the second PhD topic offered by the consultant. Both cooperating workplaces are equipped by necessary facilities i) mechanically stirred reactor, ii) bubble column and iii) air-lift reactor. All bioreactors are adapted to measure transport characteristics by the same methods, therefore the results will be comparable. Requirements for an applicant: master degree in chemical or mechanical engineering, organic technology, biotechnology etc.; ability for teamwork; systematic and creative approach to scientific problems; interest in experimental work. Student's scholarship, according to the law valid from September 2025, will be supplemented by the research group's financial resources obtained through industrial collaboration (VIK 409 82 00 53), and by the resources by The Czech Science Foundation, when the project granted from January 2026. Advanced Photocatalyst Design for Sustainable Chemical Processes
AnnotationThis PhD project focuses on designing and synthesizing novel 2D materials for heterogeneous photocatalysis. Strategies include doping with transition metals or heteroatoms, templating with supporting materials to increase surface area, and optimizing morphology through the supramolecular assembly of precursors. The research will also emphasize bandgap tuning of the heterogeneous photocatalysts for visible light-driven transformations. The optimized photocatalysts will be applied in flow reactor systems to advance sustainable chemical synthesis. Optimization of HME process and formulation of amorphous solid solutions
AnnotationAmorphous solid solutions (ASSs) are used to improve the dissolution rate of poorly soluble drugs. Despite their metastable nature, which commonly leads to a higher dissolution rate, the selection of suitable polymers and the optimization of the ASSs production process is a rather complicated task. To reduce the time and material requirements, in the proposed project, we plan to start with the screening of suitable polymers leading to solubility enhancement of the selected drug. In the next step, we will perform rheological characterization of the mixtures of promising polymers and selected drugs. This will consist of polymer-drug powder rheology and polymer-drug melt rheology measurement, resulting in the identification of critical process parameters of hot-melt extrusion (HME), i.e., powder flowability in the feeder, maximum feeding rate of the powder mixture into the extruder, minimum melting temperature of the polymer-drug mixture, maximum drug loading in the polymer-drug melt, viscosity of the polymer-drug melt and possible conditions for drug or polymer degradation. Since rheological measurement is fully automated and requires only a fraction of the material than HME itself, the proposed method will allow a significant reduction of time and material requirements for the optimization of HME. Obtained data will be used to construct dimensionless characteristics of the HME process suitable for easy setup of the process parameters and process scale-up. While HME is commonly used for the production of ASSs in the form of filaments, which are consequently milled into particles to be used in the final drug product, in the proposed project, we plan to extend the formulation of ASSs in the form of films or spherules. Taking advantage of HME as a continuous process, in the following step, we would extend this capability towards film formation or production of spherical particles. On-line Raman spectroscopy will be used to control the quality of the final product. This will be combined with off-line characterization (i.e., XRD, DSC, NMR, IDR measurement) to ensure the production of stable ASSs with enhanced drug dissolution rate. Advanced computational approaches to design and scale-up of nanocrystal manufacturing processes
AnnotationNanocrystalline suspensions of poorly soluble active pharmaceutical ingredients (APIs) have been shown to be superior to amorphous solid dispersions in terms of dissolution rate enhancement, stability, excipient dilution, and manufacturing simplicity. Industrially, aqueous nanosuspension can be achieved by top-down (wet stirred media milling) or bottom-up (antisolvent precipitation) processes. Both approaches have advantages limitations due to dilution, colloidal stability, sensititity to mechanican and thermal stress, and the required particle size distribution. Antisolvent precipitation is sensitive to the mixing step, and the supersaturation profile denerated during solvent-antisolvent mixing. To understand and quantify these phenomena, mathematical models that combine fluid mechanics, population balances, solute thermodynamics and kinetics are a useful tool. The aim of this project is to develp and implement such models, perform validation against experimental data, and apply them to real-world case studies. Advanced manufacturing concepts for flexible dose combinations
AnnotationFixed dose combinations (FDC) are drug products containing two or more active pharmaceutical ingredients whose combined therapeutic effect has been proven to be superior to that of individual components. Numerous clinical studies show significantly improved life expectancy of patients using FDC compared to their individual counterparts, especially in the cardiovascular area. For large therapeutic areas, it is common to develop FDCs e.g. in the form of bi-layer tablets for the most prescribed combinations of drugs and their strengths, e.g. candesartan and amlodipine. However, smaller, or more marginal patient cohorts are not served by this approach. The aim of this project is to develop and implement novel manufacturing concepts based on the post-mixing of mass-produced single-component subunits (e.g. minitablets), and thus achieve flexibility for small batch manufacturing of FDC products with a broader range of dosage strength combinations and/or interchangeable active ingredients. Process measurement of hydrogen concentration - Development of a measurement device prototype Hmeter
AnnotationHydrogen usage broadens across many industrial branches. Therefore, its concentration measurement becomes more important. We further focus on one of the H2 concentration measurement techniques, which ingeniously employs chemical engineering aspect of diffusion, especially to the measurement in a primary coolant of nuclear power plants (NPP). While a plenty of companies offer oxygen sensors suitable for the measurement in the primary coolant, the hydrogen sensor, really selective to H2 concentration, is offered rarely. For this reason, the functional sample of hydrogen sensor was developed in the Mass Transfer Laboratory, including its verification in the NPP Dukovany. This work aims to developme the prototype rising from the verified functional sample. The experience gained during the development of oxygen concentration measurement in recent years will be used. Not only will the student get familiar with an academic research methods but also will get to know the specifics of the operational measurement, including modern data acquisition systems. The student's scholarship will be supplemented through the Czech Technological Agency project No. TA ČR TK05020081. Gas - Liquid Mass Transfer. Experimental comparison of various apparatuses performance - Cotutelle with UNIPA
AnnotationThe volumetric mass transfer coefficient (kLa) plays a crucial role in industrial design in the case of the process controlled by gas–liquid mass transfer. Prediction of kLa is nowadays mostly based on literature correlations. Our research goal is to establish suitable kLa correlations for different types of devices that would be based on the experimental dataset. The PhD thesis aim at the comparison of various gas-liquid contactor types from the viewpoint of their mass transfer efficiency. The suitable correlations will be developed that would be viable for mechanically agitated gas–liquid contactors and also for pneumatically agitated gas–liquid contactors such as airlift reactor. Student's scholarship, according to the law valid from September 2025, will be supplemented by the research group's financial resources obtained through industrial collaboration, and by the resources by The Czech Science Foundation, when the project granted from January 2026. High-throughput robotic design of powder formulations
AnnotationMixing rules for the prediciont of physico-chemical properties of fluids from pure components are relatively well-established in the scientific literature, but still lacking in the case of multicomponent powder blends. The knowledge of powder properties such as bulk density, flowability, compresibility, permeabilty, wetting or redispersibility in water is crucial for rational design of formulation in the pharmaceutical industry. The aim of this project is to implement an automated robotic platform for programmable high-throughput robotic platform for the combinatorial preparation and testing or powder mixtures, and then to devise predictive models (possible using machine learning approaches) for the estimation of mixture properties from pure component propeties. The project will suit an individual with interest in powder mechanics, robotics, and computer programming. Controlling of drug crystal properties during crystallization
AnnotationActive Pharmaceutical Ingredients (APIs) are commonly small molecules that are used in the form of particles prepared by the crystallization process. Properties of prepared crystals (i.e., physico-chemical but also formulation properties) are strongly dependent on the used drug solid form, their size, and crystal morphology. The process of spherical crystallization results in the formation of crystals assembled into spherical particles. The goal of this project is to investigate the possibility of using this procedure for the preparation of crystalline drug particles of various polymorphs and multicomponent solid forms (i.e., cocrystals) or even conglomerates containing multiple drugs in a single spherical particle. In addition, the process will be optimized to be operated in a continuous mode. Furthermore, the students will also be involved in the automation of the whole process consisting of the mixing of crystalizing streams containing a drug (drugs) and excipients but as the operation of the stirring unit where spherical crystallization is taking place using process analytical technology (characterization of particle size, shape, and composition). Obtained particles will be characterized by several analytical methods (i.e., SEM, XRD, DSC, NMR, measurement of the dissolution rate of a single particle) and their properties will be compared to those measured for crystalline particles of drugs prepared by classical cooling crystallization. Separation of organic vapors and gases with tailored membranes
AnnotationPoly(ionic liquid)s, metal-covalent organic frameworks and planar nanoparticles, carbon or otherwise, are breaking new ground in improving the separation capabilities of polymer membranes for the separation of gases and organic vapors. This kind of functionalization of polymers also leads to the suppression of negative phenomena such as plasticization and aging that limit the use of a new generation of polymeric materials with excellent separation properties. The aim of this work is to investigate the effect of the type and amount of functionalization on the transport-separation parameters and the structure of membranes. The study of the transport and separation properties will be carried out using automated systems to measure the permeation of gas and organic vapor mixtures. Also, the possibilities of predicting transport parameters using physical models and machine learning methods will be explored. Required education and skills: • Master degree in Chemical Engineering, Physical Chemistry or any relevant field; • interest in science, willingness to do experimental work and learn new things; team work ability. Reduction of materials consumption in pharmaceutical manufacturing processes
AnnotationMany pharmaceutical tablets contain a large volume of excipients without any obvious technological or clinical benefit. Often the excipient volume is simply a consequence of a lack of (or no need for) formulation optimisation during the developement of the original drug product. However, for large-volume medicines after orginal patent expiry, there are numerous reasons for trying to reduce the volume of excipients in tablets. These include economic (cost of materials, production time), environmental (size of packaging, carbon footprint of production and distribution), quality (excipients are often the source of reactive impurities that result in degrataion) and clinical (large tablets are more difficult to swallow). Therefore, the aim of this project is to identify pharmaceutical producst with the most significant potential for excipient reduction, to refurmulate such products while maintaining bioequivalence, and to demonstrate manufacturing and/or patient benefits. General methodology for excipient reduction based on the material properties (e.g. flowability, adhesion) will be develped. The project will be conducted in cooperation with an industrial partner and will involve real-world case studies. Transport and sorption of gases in heterogeneous systems
AnnotationThe PhD project focuses on the study of gas sorption processes in heterogeneous systems using numerical simulations (CFD) and experimental methods. The aim is to analyze in detail the mechanisms of sorption, transport, and interaction of gases within non-homogeneous structures. The combination of CFD modeling and experiments will provide a comprehensive perspective on sorption kinetics, the influence of material structure, and gas transport mechanisms. The research investigates changes in sorption behavior as a function of material properties, temperature, pressure, and system geometry. Emphasis is placed on the characterization of sorption mechanisms and their impact on gas transport in heterogeneous environments. The study aims to deepen the understanding of sorption processes and to optimize them for applications in environmental technologies, gas storage, catalysis, and separation processes. Required education and skills • Master's degree in chemical engineering, mathematical modeling, and computer science; • high motivation, willingness to learn new things; • team spirit. Advancing Mass Transport in Multiphase Photomicroreactors
AnnotationPhotocatalysis provides efficient synthetic pathways and broad substrate diversity, making it particularly valuable for late-stage modifications in drug discovery. Advancing mass transfer is critical for effective photochemical transformations, and this project focuses on enhancing it through the transition to flow photomicroreactors. Computational Fluid Dynamics (CFD) simulations will be integrated with the experimental design of photomicroreactors to optimize mass transfer. Experimental data combined with CFD outputs will serve as input for machine learning algorithms to optimize the system and identify the Pareto front for optimal performance. Triboelectric routes enabling plastic waste separation and recycling
AnnotationRecycling is the most beneficial and eco-friendly way to treat large amount of plastic waste. However, conversely to a public belief, the majority of plastic waste is burned in incineration plants or stored in landfills instead of being recycled. The bottleneck of the plastic waste treatment originates in the pre-separation, as only precisely separated waste can be recycled. Even the incineration process requires the pre-separation of plastics, mainly the removal of polymers containing halogens that could otherwise form harmful gases during combustion. Current methods like manual separation, IR spectroscopy or methods based on density differences aren’t sufficiently effective. The new promising technique, triboelectric separation, is based on the idea that each plastic material reaches different electrostatic charge by tribocharging (charging by friction) and therefore charged plastic mixtures can be separated in electric field. The objective of this Ph.D. project is the establishment of experimental bases (systematic series of data) related to charging and discharging dynamics in powders, which will provide integrated description of these phenomena. The student will also investigate opportunities for control of surface charge and subsequent separation of dielectrics in electric field. The student shall challenge several open problems: (i) relation between ESC and mechanical/chemical properties of materials, (ii) electric charge dissipation, (iii) charging of powders under the conditions simulating real industrial production of industrially important powders, (iv) the effect of charge on fouling, (v) charging for separation and recycling of plastic materials. The project is a pioneering work which is desperately needed and is sufficiently challenging for a student with interest in physico-chemical fundamentals of previously described processes. The student will work with highly qualified Ph. D. students and postdocs in our research group and will also cooperate with our European partners. Our laboratory is well prepared for the research of electrostatic processes (Faraday cup, corona charging, high-voltage separator) and characterization of powder texture and material properties (micro-tomography, atomic force microscopy – AFM). Info: phone 220 44 3296, office B-145, e-mailjkk@vscht.cz, web http://kosekgroup.cz The influence of adhesive forces on the behavior and interactions of particles in granular materials
AnnotationThe PhD project focuses on the influence of adhesive forces on the behavior and interactions of particles in granular systems. The goal is to analyze in detail the impact of adhesion on the dynamic behavior of particle structures using numerical simulations and experiments. The research combines the Discrete Element Method (DEM) with experimental validation to provide a comprehensive perspective on adhesive phenomena in particle systems. The study examines the effects of adhesive forces on particle aggregation, clustering, and mechanical behavior, taking into account material properties, surface energy, and external conditions. The focus is on the characterization of adhesive mechanisms and their impact on the macroscopic behavior of particle structures. The research results can contribute to a deeper understanding of adhesion mechanisms and their application in materials engineering, the pharmaceutical industry, and nano-/microtechnologies. Required education and skills • Master's degree in chemical engineering, mathematical modeling, and computer science; • high motivation, willingness to learn new things; • team spirit. Interfacial phenomena in polymer recycling
AnnotationThe objective of this PhD project is to generate fundamental knowledge and validated tools capable to immediately aid in the design of solvent-based recycling unit operations, their optimization and scale-up, screening of solvents and their regeneration. Solvent-based recycling can contribute to generating recycled plastics comparable in their performance to freshly synthesized polymers. Particularly, this project will focus on three subjects: The first one is the modeling of thermodynamics of polymer-diluent-additive systems by advanced PC-SAFT equation of state, where parameters for PC-SAFT will be supplied by quantum mechanical (COSMO-SAC) approaches. The polydisperse nature of polymers makes this task challenging. The second focus will be in the modelling of interfacial phenomena at polymer-gas, polymer-liquid, and polymer-additive interfaces. The aim will be to employ thermodynamically self-consistent approaches including DGM (density gradient methods). The last focus will be on providing data for the validation of interfacial phenomena modeling from various experimental techniques including AFM, Raman spectroscopy, confocal laser scanning etc. PhD student is expected to be involved in projects of applied and fundamental research and in bilateral collaborations with industry related to PhD project. Moreover, the stay at foreign academic institution (e.g., in Austria) is anticipated. Contact information: Juraj.Kosek@vscht.cz , Dept. of Chem. Engineering, UCT Prague. Effect of interfacial properties on dynamics of bubbles
AnnotationMultiphase systems consisting of a gas phase dispersed in a liquid environment are omnipresent in nature and in living systems. Gas-liquid contact is also responsible for the success of many industrial processes, such as flotation, or aerated reactors. Surfactants, SAS, with their ability to lower the interfacial tension between gas-liquid phases, alter the behavior of many multiphase processes, and for many systems, the characterization of the interface by surface tension alone is not enough and less conventional measurements of surface rheology and SAS adsorption/desorption characteristics are crucial. The aim of this work is to determine experimentally the influence of surfactants on the dynamics of processes with bubbles (movement, dissolution, coalescence, etc.) and to characterize selected SASs by measuring relevant physico-chemical and transport properties. The typical work will include measurements of interfacial rheology, observations of bubble dynamics by high-speed camera, but also building single-purpose experimental equipment and physical interpretation of results. Required education and skills • Master degree in chemical or mechanical engineering or in physical chemistry; • Systematic and creative approach to scientific research, teamwork ability. High-Throughput Experimentation in flow photomicroreactor
AnnotationThis project aims to develop a platform combining high-throughput experimentation (HTE) with flow photomicroreactors to create efficient, scalable, and green catalytic processes. Addressing the complexity of catalytic reactions, varying catalysts, substrates, and reaction conditions, requires moving beyond traditional one-variable-at-a-time methods. HTE enables rapid screening of catalysts and conditions across diverse transformations, while translating photochemical reactions into flow reactors reduces reaction time and enhances discovery. The student will design workflows integrating segmented flow in microreactors, where each reaction parameter is tested in individual liquid slugs, enabling efficient and systematic exploration of the reaction design space. HTE in the flow photomicroreactor will be coupled with in-line analysis to distinguish effective and ineffective interactions. This data will be used to create heat maps, providing a visual representation of reaction performance and guiding optimization strategies. Utilization of inter-and intra-molecular interactions in modelling of drug-polymer systems
AnnotationInterparticle interactions play a significant role during the process of micelle formation, stabilization of nanoparticles during antisolvent precipitation, stabilization of drug molecules in supersaturated solution during drug dissolution, or even in the process of selection of suitable polymers to prepare amorphous solid dispersion. In this thesis, we would like to utilize quantum mechanics and all-atom molecular dynamic simulations to tackle the above-mentioned challenges. The first studied system will contain a selection of suitable polymers to prepare an amorphous solid solution (ASS) with the selected drug while maximizing the long-term stability of ASS. In addition, we plan to study the interaction of selected polymers with a drug in a water environment to maximize drug solubility and prevent drug precipitation from supersaturated solution. The second studied system will consist of surfactant molecules (both synthetic and natural) in a water environment where we plan to study the impact of concentration of surfactant molecules, length of hydrophobic and hydrophilic chains, presence of ionic strength or temperature variation on the formation of micelles/surfactant molecule coils. Particular attention will be considered when drugs are added to this system, where the goal will be to understand the solubilization of drug molecules in the surfactant micelles. Obtained results will be compared with available experimental data containing the solubility of the drug in a polymer, time evolution of drug concentration in the supersaturated solution stabilized with polymer, or permeation measurement of drug molecules in the presence of surfactants and polymers. Simulations will start from quantum-chemical calculations of the COSMO-RS type to enable the first and relatively quick qualitative estimation of Hansen's solubility parameters and can thus serve in the initial screening of suitable polymers. In the next step, molecular dynamic simulations will be used to simulate the polymer-drug affinity in a real system arrangement (ideally including basic experimental knowledge). Application microfluidic devices to study interdisciplinary problems in fields of chemical engineering and medical diagnostics
AnnotationMicrofluidic devices play a key role in bridging the fields of chemical engineering and medicine, enabling interdisciplinary exploration. These miniaturized systems manipulate small fluid volumes, offering precise control for studying biological processes and drug delivery. In chemical engineering, microfluidics aid in optimizing reactions, enhancing process efficiency, and developing advanced materials. Simultaneously, in medicine, these devices facilitate intricate analyses of cells, biomolecules, and disease mechanisms. This thesis will address the integration of microfluidic devices to study the progression of chemical and biological processes in field of personalized medicine and diagnostics. The candidate should have an interest in chemistry or biochemistry and has good relation to experimental laboratory work to perform tests with microfluidic devices, as well as with data acquisition and evaluation. To complete the delegated tasks, the personal abilities such as independence, creativity, open mind and team work skills will be required. Application of microreactors to study gas phase catalytic reactions
AnnotationMicroreactors are promising devices that are increasingly finding widespread application in many chemical processes. Their advantage is that by a suitable microreactor design with respect to the studied process, their reaction space geometry allows to study reactions or test catalysts under conditions without mass and heat transport limitations. Therefore, the scope of the present topic is to study catalytic gas-phase reactions using microreactors in order to optimize the process. The work will include experimental laboratory tests with model reactions, data processing, mathematical description of kinetics and transport variables with the aim of designing the microreactor for the optimal course of the studied reaction and maximum spatial yield. The ideal candidate should have a strong knowledge of chemical and reaction engineering, as well as a positive attitude towards using data acquisition systems, data evaluation, and mathematical modeling. Independence, creativity, teamwork skills, a willingness to learn, and proficiency in the English language are also required for this role. Development and synthesis of nanoparticle systems for phototherapy
AnnotationCo-processed active pharmaceutical ingredients for direct compression
AnnotationActive pharmaceutical ingredients (APIs) in high-dose tablets (e.g. metformin, ibuprofen) would benefit from as little dilution by excipients as possible to keep the tablet weight down, while maintaining processability (bulk density, flow behaviour, compressibility, etc.). Co-processing is a rapidly emerging approach that aims to combine the API with a small amount of excipient while achieving large differences in processability, usually by the modification of surface properties, particle size and morphology. The aim of this project is to explore co-processing concepts for several chosen APIs based on both dry and wet routes, and to demonstrate that co-processed APIs can be manufactured in a scalable and reproducible manner. The ultimate aim is to utilise co-processes APIs in direct compression, i.e. the manufacturing of high-dose tablets without any granulation step. Upcycling of plastics enabled by the recovery of additives
AnnotationThe objective of this PhD project is to generate fundamental knowledge and validated tools capable to immediately aid in the design of solvent-based recycling unit operations, their optimization and scale-up, screening of solvents and their regeneration. Solvent-based recycling can contribute to generating recycled plastics comparable in their performance to freshly synthesized polymers. Particularly, this project will focus on three subjects: The first one will be the fast screening of solvents and fast optimization of conditions for the removal of various types of molecular or particular additives. This task will be supported by advanced thermodynamic modeling. In some situations, the recovered additive can be the main product due to high-cost of some additives. Entire flowsheet including recycling of solvents will be considered. The second objective is to approach polymer ageing and degradation during its life-time in relation to recycling, i.e., characterization of the extent of ageing and removal of aged fractions. The third focus will be textile recycling focusing on synthetic fibers and mixture of synthetic/natural fibers. Here additives play a role in coloring, control of hydrophobicity and other aspects. PhD student is expected to be involved in projects of applied and fundamental research and in bilateral collaborations with industry related to PhD project. Moreover, the stay at foreign academic institution (e.g., in Austria) is anticipated. Contact information: Juraj.Kosek@vscht.cz , Dept. of Chem. Engineering, UCT Prague. Scale-up of wet nanomilling and nanocrystal formulation processes
AnnotationDried nanocrystalline suspensions of poorly soluble active pharmaceutical ingredients (APIs) have been shown to be superior to amorphous solid dispersions in terms of dissolution rate enhancement, stability, excipient dilution, and manufacturing simplicity. The formation of aqueous nanosuspension can be achieved in wet stirred media mills that can be operated in a batch mode during process development and then scaled up to flow-through arrangement either in recirculation or single-pass mode. The suspension can then be easily dried to obtain granular material suitable for direct capsule filling or direct tabletting. The aim of this project is to develop and validate a robust scale-up methodology for the manufacturing of nanocrystal suspensions by flow-though wet milling at the highest possible concentration, subsequent spray during or fluid-bed drying, and processing into a final dosage form (tablets, capsules). For a chosen API, the entire process from raw API to finished products will be demonstrates and the product pharmaceutical performance (stability, in vitro dissolution, in vivo bioavailability) will be evaluated. |
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Updated: 9.2.2024 12:34, Author: Jan Kříž