The Marie Sklodowska Curie European Training Network SOCRATES offers a unique training programme for 15 early stage researchers (ESRs), bundling and strengthening European skills and knowledge through an intersectorial and interdisciplinary cluster of excellence. That is our projects’ nicely put slogan or baseline. In this blog, I will describe how the SOCRATES project puts these nice words into reality.
SOCRATES aims at laying the foundations of a diversified and sustainable supply chain for critical metals, with a focus on Ge, In, Ga and Sb. It develops game-changing technology combinations: 1) to extract metals from distinct industrial-process residues, 2) to recover the metals from the extraction process, 3) to valorise the residual matrix into engineered products while performing an integrated assessment of the new flow sheets.
My role in this project is to undertake an advanced characterisation and mapping of the complex residues, before and after the removal of metals by leaching. Different experimental methods with a high sensitivity and a high spatial resolution (synchrotron methods, EPMA-WDS, etc.) are used. Last January and February, I had my secondment at KU Leuven (Belgium) on a research project with a specific focus on advanced EPMA-WDS characterisation of the SOCRATES residues.
An Electron Probe MicroAnalyzer (EPMA) is an analytical tool used to non-destructively determine the chemical composition of small volumes of solid materials. The sample is bombarded with an electron beam, emitting x-rays at wavelengths characteristic to the elements being analyzed. This enables the abundances of elements present within small sample volumes (typically 10-30 cubic micrometers or less) to be determined. The concentrations of elements from beryllium to plutonium can be measured at levels as low as 100 parts per million (ppm). Recent models of EPMAs can accurately measure elemental concentrations of approximately 10 ppm [1]. As a result, EPMA can be a very useful tool and in our case was used in order to trace the exact amount of economically important elements and in which phase they occur.

Picture of the electron probe microanalyzer (EPMA) of KU Leuven
But why did I come at KU Leuven and not somewhere else? The answer is simple! Because dr. Annelies Malfliet is experienced with EPMA but also with the kind of materials that we have to deal with in SOCRATES project. So, for 2 months I had the chance to learn from the best. During my time in KU Leuven, I learnt about the preparation steps of the samples for the EPMA but also how to operate the instrument. Last but not least, a crucial step was also analyzing the data that I obtained. The above-mentioned made this so interesting for me as I became more experienced and familiar with this technique.
The time I spent in Leuven gave me the opportunity to gain experience on EPMA while I widened my technical knowledge. My secondment in KU Leuven was a fruitful experience. My supervisors, prof. Philippe Muchez and dr. Annelies Malfliet, helped me during the secondment and encouraged me to learn from my own mistakes and asked me many stimulating questions. One more advantage of doing a secondment in KU Leuven is that I could work closer with my SOCRATES colleagues. It was easier for us to exchange ideas and talk about the progress that we are doing in our research.
Now that I am back in Utrecht and thinking these two months in Leuven, I want to remember the knowledge that I gained and the amazing time that I spent with my friends and colleagues Christina Siakati (ESR12), Niki Pouliou (ESR7) and Stylianos Spathariotis (ESR5).
[1] https://en.wikipedia.org/wiki/Electron_microprobe