Student Projects

Master Thesis / Construction Thesis– Optimizing a continuous crystallization process via Machine Learning Approaches


The industrial interest in continuous processes in general, and especially in the field of crystallization, increased very much in the last years. Although a lot of interesting approaches exist, there is still a great need of automation and optimization of this unit operation in order to increase profit margins as well as the understanding of the applicability of continuous crystallizers. Combining automated set-ups with machine learning optimization algorithms offers exciting new possibilities in this regard.

Therefore, the goal of this project is the optimization of a continuous crystallization process via machine learning approaches.

In particular, the tasks of the thesis are:

  • Expansion of an existing experimental set-up with inline sensors for particle measurement. The set-up includes a lab-scale fluidized bed crystallizer that was designed and manufactured in-house using 3D-printing (see picture) and is used for the crystallization of an active pharmaceutical ingredient.
  • Adaptation of an existing machine learning framework. The framework was developed in Python for the algorithmic optimization of chemical reactions in flow and should now be adapted for crystallization approaches.
  • Combination of the experimental set-up and the machine learning algorithms in order to self-optimize the crystallization process.


  • Background in chemical and/or pharmaceutical engineering, chemistry or similar areas
  • Basic laboratory work experience
  • Interest in the above-mentioned topics
  • No programming knowledge needed (but being interested is advantageous)

Dipl. Ing. Sebastian Soritz - +43 316 873 – 30409
Dipl.-Ing. Nys Nico -  +43316873  30438
Prof. Heidrun Gruber-Wölfler +43316873 - 30406

Master’s thesis - Design of a multistep (photo)biocatalytic process for the production of biopolymers

Photo- and biocatalysis have recently emerged in the field of organic synthesis as greener alternatives to conventional processes, since the combination of both technologies is of great interest to reduce the environmental impact of fine chemical production. However, (photo)biotransformations are limited by the low stability of many enzymes of interest (e.g. oxidoreductases) outside living cells, their cofactor dependency, as well as poor light distribution and harvesting. These disadvantages constrain the scale up of photobiocatalytic processes and their industrial application. To overcome these limitations, the utilization of continuous processes could be a solution. Flow reactors pose many advantages, especially due to their small inner dimensions and high surface area, which allow for better heat and mass transfer, as well as improved illumination efficiency.

In this project, continuous flow reactors for whole-cell photobiocatalysis will be investigated and implemented in a multistep process. The stability and activity of photoautotrophic cells as biocatalysts will be optimized by testing different process parameters. The setup will be further expanded to develop a multistep cascade for the production of highly valuable compounds, such a biopolymers, which are relevant to the pharmaceutical industry. The process can be flexible and feature different modules: reaction modules that can host packed bed reactors filled with the immobilized (bio)catalyst, as well as modules for other unit operations (e.g. mixing, quenching, extraction), as shown in Figure 1. The different steps will need to be optimized and tested, and the process will be improved to achieve high space-time-yield. The possible challenges include: finding an optimum light intensity that minimizes cellular photo stress; testing different reactor geometries to improve illumination efficiency; the choice of an optimal solvent compatible with multiple reaction steps; the possible interaction of byproducts within the system. To increase process understanding and efficiency, the possibility of implementing process analytical tools, such as inline sensors for real-time analyses, will be explored as well.

Figure 1Generic scheme of a multistep photo-biocatalytic reaction process.

• Literature study on industrial photo- and biocatalysis in continuous flow and whole-cell immobilization
• Study of the single catalytic steps in batch
• Design of an adequate multistep continuous process (possibly including reactor design)
• Optimization of the reaction/process conditions
• Implementation of real-time analytics (e.g. UV-vis probes)

• Background in chemical engineering, chemistry or biotechnology
• Interest in the above mentioned fields
• Lab work experience (master student level)

What we offer:
• Integration in an internationally leading institute (IPPE) of TU Graz
• Support from the CoSy Pro Team
• Paid master Thesis

At any time

Dipl. Ing. Dott.ssa Alessia Valotta     +43 316 873 – 30428
Assoc. Prof. Dipl.-Ing. Dr.techn. Heidrun Gruber-Wölfler

Master Thesis - Image Analysis for Continuous Cooling Crystallization


For this master thesis we are looking for a student to implement an automatic image analysis with MathWorks MATLAB which gets applied for continuous cooling crystallization in a tubular reactor (plug flow crystallizer). The necessary images are captured by a HQ camera that is part of the single board computer platform Rasperry Pi.

Picture 1: Progress of encrust formation

Crystallization is an important unit operation in the chemical and especially pharmaceutical industry for the separation and purification of high-value products, such as active pharmaceutical ingredients (APIs). Currently most of the crystallization processes applied in pharmaceutical industry are operated in batch. Due to batch-to-batch variations in product quality, lower productivity and higher energy consumption, efforts are made to move towards continuous operation using either stirred crystallizers or tubular set-ups. While having a fast mixing and an excellent heat transfer, one drawback of tubular crystallizers is that solid deposits (encrusts) form on the surfaces and inner walls (see Picture 1). Over time this leads to cross-sectional narrowing. Therefore, the goal is to quantify the effects of different designs and process conditions on encrustation and to find a way to prevent solid formation and clogging in tubular crystallizers (see Picture 3).

Picture 2: Cooling bath with window installation for visual observations and the camera setup

A special cooling bath with window inserts which allows the visual observation of the crystallization process within the tubular crystallizer has already been designed and assembled (see Picture 2). Building upon this an automated continuous image analysis program should facilitate the non-invasive and in-line evaluation of the encrust formation progress.


  • Application of the HQ camera setup with the single board computer (SBC)
    Rasperry Pi suited for the cooling bath setup (see Picture 2 and Picture 3).
  • Transfer the image data from the SBC to MathWorks MATLAB.
  • Implement an automated image analysis program in MathWorks MATLAB by means of greyscale transformation and determination of pixel intensities to evaluate the development of encrust formation within the tubular crystallizer.
  • Additional features, e.g. particle tracking or particle image velocimetry (PIV) optional
Picture 3: Setup schematic for encrustation investigation

Your profile

  • Background in process, chemical, pharmaceutical engineering or chemistry
  • Basic experience in lab work
  • Basic experience and interest in coding
  • Basic experience with MATLAB recommended
  • Experience with single board computer (Arduino, Rasperry Pi, etc.) of advance

What we offer

  • Integration in an internationally leading team
  • Flexible working times
  • Paid master thesis

About us

  • Working group with focus on continuous synthesis and processes of Assoc. Prof. DI Dr. Heidrun Gruber-Wölfler
  • Team consists of chemists, chemical and process engineers


Dipl.-Ing. Alexander Meister, BSc
Inffeldgasse 13/III
A-8010 Graz

Paid Master’s Thesis – Improving a Continuous Flow Reaction Calorimeter


For the optimization and scale-up of chemical processes, knowledge about thermal parameters is vital to design chemical reactors. Measuring these parameters, such as mixing or reaction enthalpy, demands specialized equipment.

The goal of this project is to optimize the design of an already established flow calorimeter. This is done to broaden the scope of possible reactions that can be investigated. The work touches upon the topics of sensor technology, Arduino microcontrollers and - electronics, and flow chemistry. The work is carried out in close cooperation with RCPE GmbH.

For the full announcement see:  ReactionCalorimetry


Dipl. Ing. Sebastian Soritz
 - +43 316 873 - 30409

Assoc. Prof. Dipl.-Ing. Dr.techn. Heidrun Gruber-Wölfler

2 Master Thesis Projects - Chemical Engineering (Verfahrenstechnik) or Chemical and Pharmaceutical Engineering (CPE)

Trocknung und Lagerung und von Monomeren in der Polymerproduktion

Die Qualität von Monomerpartikel ist von entscheidender Wichtigkeit für die finalen Eigenschaften vieler Polymerprodukte (z.B. Acrylglas, Lacke, etc.). Bei der Herstellung von Monomerpartikeln ist der Trocknungsschritt von hoher Wichtigkeit für mögliche Veränderungen der Partikel während der Lagerung, die in weiterer Folge das Produkt beeinflussen.

In Zusammenarbeit mit unserem Partner (einem großen Hersteller dieser Monomere) vergeben wir zwei Masterarbeiten für Verfahrenstechnik- bzw. CPE-Studierende. Ziel dieser Arbeiten ist eine tiefgreifendere Analyse der chemischen und physikalischen Veränderungen während der Trocknung bzw. der Lagerung eines granularen Monomers. Diese Analyse erfolgt großteils auf Basis von experimentellen Arbeiten, z.B. Partikelgrößenanalyse, MS, HPLC, oder einem neu zu entwickelnden Trocknungsexperiment. Weiters ist für den Teil „Trocknung“ die Weiterentwicklung eines Berechnungsprogrammes, sowie eine Auslegung durch­zuführen.Abbildung: Ein typisches Produkt unseres Projektpartners (Bildquelle:

Wir bieten:

  • höchste industrielle und wissenschaftliche Relevanz
  • modernste Ausrüstung am Institut
  • Unterstützung durch das Projektteam am IPPT (Analyse, Literatur, Aufbau eines Trocknungsexperimentes, Software)
  • Schreibtisch und Büroräume
  • Vergütung (Anstellung bei unserem Partner, oder am Institut)


Stefan Radl,, 0680 / 12 22 168

Heidrun Gruber-Wölfler,, 0316 / 873 30406.

Möglicher Startzeitpunkt: 1. Jänner 2022

Paid Master’s Thesis – Molecular Dynamics Simulations of Transport in Polymers

Polymers are used in the electrical industry to insulate devices. Especially in corrosive atmospheres the investigation of the degradation of these polymers and the protected devices is of vital importance to increase their longevity. One main influence is the diffusion of corrosive substances through the protective layer of a device. In recent years as computational power became cheaper, using molecular dynamics simulations to quantify transport properties of polymers became more commonly used.

In this thesis molecular dynamics (MD) simulations should be used to quantify the transport processes of different penetrator molecules in polymers. Investigations regarding the polymer’s chain-length, the degree of cross-linking, as well as the charge of the penetrator molecules under different environmental conditions should be conducted.


  • Running and analyzing molecular dynamics simulations of polymers
  • Investigation of physical properties of polymers


  • Solid background in chemical engineering
  • Knowledge of Matlab or Python
  • Enthusiasm to work with theories, software, and computer algorithms
  • Interest and enthusiasm for performing simulation on supercomputers

Work on the thesis is paid (6 months), and we offer office space, computers, simulation software and expertise, as well as integration to a highly-relevant research project

Dr. Stefan Radl (; 0680 12 22 168)
Dipl.-Ing. Philipp Mayr, BSc. (

Paid Master Thesis or Student Job - Developing a Novel Drug Delivery System for Special Patients


The Institute of Process and Particle Engineering is a world leader in the development of pharmaceutical products and processes.

In this context, we are offering a paid master thesis where the student is employed at an external company.

The goal of the master thesis is to create the basis for product development, focusing on a novel drug delivery system where the medicine is contained in a flavored gel, either as solution, emulsion or suspension. Drug delivery occurs via breaking a seal of a snap-package and sucking out the flavored gel. Target patient populations includes:

  • Geriatric patients (frail & old patients)
  • Pediatric patients (kids)
  • Emergency applications


  • Literature study on competitor products and patent situation
  • List of the 20-30 most important medicines for the three target populations and corresponding biopharmaceutical classification
  • Research on formulation strategies (solutions, emulsions, suspension) with sufficient stability
  • Selection of 3 model APIs (different categories) and formulation of the gels
  • Stability testing under stress conditions


  • Background in pharmaceutical sciences, pharmaceutical engineering or medicines
  • Student in pharmacy, pharmaceutical engineering, chemical engineering or related

What we offer:

  • Integration in an internationally leading team
  • Opportunity to be part of a commercialization project
  • Paid thesis

Start: Spring 2021

Contact: Univ.-Prof. Dr. Johannes Khinast,

Paid Master Thesis or student job: Comparing Bioreactors with different scales and/or geometries


The Institute of Process and Particle Engineering is a world leader in the development of simulation tools for industrial-scale bioprocessing units, funded by the Spin-Off Fellowship Program of the FFG. For example, our current code can model processes in large-scale bioreactors, up to 200m3 .
We are therefore offering a student job with the possibility to do a master thesis with the goal of creating a comparison algorithm for bioreactors. The objective is to find the influencing factors that determine the productivity difference between reactors. This should be done by comparing reactors of different scales and for reactors at the same scale but different geometry and should aid scale up or process transfer processes in the industry.


  • Literature study on available influencing factors or comparison concepts for the production in bioreactors using cells or microorganisms
  • Propose an algorithm for the comparison of reactors
  • Do scale ups or process transfer virtually


  • Background in biotechnology, biochemistry, molecular microbiology or similar
  • Being familiar with industrial production in bioreactors

What we offer:

  • Integration in an internationally leading team
  • Opportunity to be part of a commercialization project
  • Paid thesis

Start: Fall 2020

Dr. Christian Witz
0316 873 30416

Michaela Cibulka

Institute of Process and Particle Engineering
Inffeldgasse 13
8010 Graz

+43 316 873 - 30403
+43 316 873 - 1030403
Office hours
nach Vereinbarung