Currently the following calls for MSc projects are open. If you are interested submit your request via the online form linked to here. First please consult our page information for students.
Supervisor(s): Christia Jabbour, Jennifer Hartong (IRAS) & Laurens Mandemaker
Title: Detection and Characterization of Micro- and Nanoplastics in Powder, Human and Cow milk
Description: In recent years, there has been a growing interest of research dedicated to understanding the potential impacts of micro- and nanoplastics (MNPs) on early-life human health. Ingestion is considered one of the most dominant routes of MNP exposure in humans. Considering the intake of milk of Dutch citizens (257 kg cow milk per capita in 2021), milk and milk products could contribute significantly to MNP exposure and possibly bioaccumulation in humans.
In this proposed research project, samples of human milk, infant formula and cow milk will be collected and analyzed for the presence of MNPs. This experimental procedure involves a degradation process (digestion) which facilitates the removal of naturally occurring fat and proteins present in the milk thereby enabling their isolation from NPs. The digested milk will go through a filtration process after which the MNPs and the residues will be imaged with Scanning Electron Microscopy – Energy Dispersive X-ray analysis (SEM-EDX). The chemical nature and identity of the particles will be assessed using Raman and/or infrared micro-spectroscopy. The products will also be tested with Pyrolysis–Gas Chromatography–Mass Spectrometry (Py-GC MS), which is an analytical technique wherein the sample undergoes heating to decomposition, generating smaller molecules that are subsequently separated via gas chromatography and identified through mass spectrometry. After optimizing the digestion, filtration and detection methods, MNPs present in the milk samples will be determined. This research will yield crucial insights into the amounts and type of MNPs found in milk supply.
Supervisor(s): Carolin Rieg
Title: Investigating structure-reactivity relations to understand the coking behavior of hydrodeoxygenation catalysts
Description: Pyrolysis of natural biomass produces bio-oil, which is not directly usable as a fuel. Due to the reactive oxygen-containing species and high water content, an upgrading is necessary. The catalytic hydrotreatment of pyrolysis oil is usually done with sulfided transition-metal deoxygenation catalysts. The consequence is an increased sulfur concentration in the stabilized pyrolysis oil. New catalysts are e.g., bimetallic NiMo and NiCu support systems based on Al2O3 or MgO. However, the drawback is coke formation combined with deactivation. The exact reason for the deactivation is not fully understood.
What will you learn?
Your project focuses on catalyst and support synthesis and/or building up a setup for catalytic reactions and/or characterization. You will investigate how the structure of the catalyst correlates with the activity and product distribution in test reactions in high-pressure setups with model compounds, e.g., guaiacol or pyrolysis oils. You can learn the basic characterization techniques in heterogeneous catalysis, e.g., N2-physisorption, H2-TPD, XRD, ss-NMR, UV-Vis, SEM, and XPS. Also, you can do operando investigations combining two or more techniques and investigate the catalyst at working conditions. A further aspect can be the optimisation of analysis methods to specify the composition of the stabilised oils.
Supervisor(s): Kirsten Siebers, Adriaan Duijndam
Title: Effect of UV-exposure on Size, Morphology, and Chemical Structure of Nanoplastics in Suspension
Description: Currently, the scientific community is showing a rapidly growing interest in polymeric particles in the micro- (< 5 mm) and nano-regime (< 1 μm)1. In the environment, these particles are formed from larger plastics, as a result of degradation caused by both biotic and abiotic factors, such as exposure to UV-light.2,3. An initial study on the effect of UV-exposure on size, morphology, and chemical structure of polystyrene (PS) nanospheres has yielded interesting and promising results. In this master project, you will extend this study to other nano-sized polymers, such as polyethylene (PE) and polypropylene (PP) and/or investigation of the effect of pH on the degradation. You will work with a set of analysis techniques; among others dynamic light scattering (DLS), scanning electron microscopy (SEM), and potentiometry (pH measurements). Additionally, an important part of the project is the development of a sound spectroscopic (e.g. IR) method to yield insights into the chemical origin of the observed degradation
1. Mintenig, S. M., Bäuerlein, P. S., Koelmans, A. A., Dekker, S. C. & Van Wezel, A. P. Closing the gap between small and smaller: towards a framework to analyse nano- and microplastics in aqueous environmental samples. Environ. Sci. Nano 5, 1640–1649 (2018).
2. Gerritse, J., Leslie, H. A., de Tender, C. A., Devriese, L. I. & Vethaak, A. D. Fragmentation of plastic objects in a laboratory seawater microcosm. Sci. Rep. 10, 1–16 (2020).
3. Delre, A. et al. Plastic photodegradation under simulated marine conditions. Mar. Pollut. Bull. 187, (2023).
Supervisor(s): Thomas Roekmann (Marine and Atmospheric Research), Luper Technologies
Title: several open positions
Description: Luper Technologies is an early stage startup working to free the world of (organic) industrial air pollution by unburdening industrial companies from their air pollution through our patented air cleaning systems. Our systems remove pollutants from industrial offgasses through the natural self-cleaning mechanisms of Earth’s atmosphere. Unlike other technologies, our systems operate fully in the gas phase. Attached a one-pager and slide deck with additional information: Luper Technologies One-Pager, Luper Technologies Introduction Slidedeck
We are currently looking for (atmospheric) chemists to help us in our journey. We’ve got several open positions for team members and interns. We’re working together with Thomas Roeckmann and the University of Utrecht, so that allows you to do your graduation project at Luper.
Feel free to reach out with any questions and we are looking forward to see how we can help each other.