Practical trainings, student assistants and theses

Lithium is in high global demand due to its suitability for a wide range of applications, particularly in rechargeable batteries for the electronics sector. This is attributed to its low mass and high energy density, which enable compact battery designs and efficient recharging capabilities of lithium-ion accumulators. In the battery electric vehicle (BEV) sector, lithium is particularly difficult to replace. Between 2010 and 2100, an estimated increase of 20 million metric tons (Mt) is expected in this field, representing a remarkable 21% rise from the 107,000 tons produced just one year earlier. This trend might be ascribed to the increasing development and demand for lithium-ion batteries in the electric vehicle sector. Currently, lithium is mined from brines, pegmatites, or sedimentary rocks. However, its limited supply, coupled with significant environmental and political challenges associated with traditional production methods, necessitates the development of alternative technologies for lithium recovery. One promising approach is the recovery of lithium from spent batteries or battery waste. This method not only helps address the global supply-demand gap but also conserves natural resources and reduces environmental impact by minimizing the need for new mining activities. Furthermore, recycling lithium from used batteries supports the creation of a circular economy, ensuring a sustainable and resilient supply chain for this critical material. However, the development of a highly lithium-selective and cost-effective materials is still challenging due to its chemical properties. The analogues of organic ligands such as crown ethers and calix[n]arens are found to be most effective for the lithium recovery due to their distinctive features, including ring size and functional attaching groups. The objective of this thesis is to design and develop various crown ethers and calix[n]arenes for the selective recovery of lithium from different battery waste solutions. The developed crown ethers and calix[n]arenes will be tested for complexation with lithium ions using various analytical techniques followed by its application in bioionflotation and liquid-liquid extraction.
Key Responsibilities:

• Conduct literature research on crown ethers and calix[n]arenes for the recovery of lithium through hydro- and biometallurgical process
• Design and conduct laboratory experiments using synthesized crown ethers and calix[n]arenes with different hydrometallurgical and biometallurgical parameters
• Optimize experimental conditions for high recovery rates for lithium and other valuable metals
• Prepare a thesis report and present findings at conferences or workshops

• Bachelor's degree in Chemistry, Chemical Engineering, Biotechnology, Environmental Engineering or related field
• Good oral and written communication skills in English or German
• Ability to work independently and systematically

• Duration: 6 months
• Start Date: Start in April 2025 is possible
• Funding: Remuneration according to HZDR internal regulations

This study examines how surface properties (particle size, porosity, surface area, ...) affect the carbonation of Ca/Mg silicate minerals or tailings, focusing on enhancing CO₂ sequestration and understanding chemical mechanisms. Advanced techniques, including BET, porosimetry, SEM imaging, particle size distribution (PSD) analysis, XRD, Raman spectroscopy, XRF, TGA, and particle shape/geometry studies will be used. A modified regrind mill setup will optimize surface area under ambient conditions to minimize passive layer formation and improve carbonation kinetics. The findings aim to support sustainable cement production by enhancing CO₂ sequestration processes and adding value to mine tailings.

• Educational background: Chemcial or Materials engineering, Process engineering or related field
• Knowledge of basic laboratory skills, analytical techniques (such as Raman spectroscopy, TGA, ICP, XRF, )
• Good English skills
• Ability to work independently

• Duration: 6 months
• Start date: as soon as possible
• Workplace: Freiberg

Emerging pollutants, such as pharmaceuticals and per- and polyfluoroalkyl substances (PFAS), pose significant environmental and health risks due to their persistence and bioaccumulation. Conventional treatment methods often fail to effectively remove these contaminants from water systems. This master’s thesis focuses on an advanced hybrid approach combining bioflotation with hydrodynamic cavitation (HC) to enhance pollutant removal efficiency. The study aims to evaluate the effectiveness of this method in degrading or separating pharmaceuticals and PFAS from contaminated water and optimizing process parameters.
Tasks:

• Selection of suitable bioflotation agents and hydrodynamic cavitation parameters for pollutant removal
• Characterization of treated water samples using analytical techniques such as HPLC and TOC analyser
• Optimization of bioflotation and cavitation conditions to enhance removal efficiency

• Field of study: Chemistry, Chemical Engineering or related field
• Experience in organic chemistry, knowledge of the techniques to synthesize compounds and to characterize them; experience in coordination chemistry, biochemistry and/or technical chemistry is advantageous
• Good oral and written communication skills in English or German
• Ability to work independently and systematically

• Working in a multi-disciplinary team
• Working place HZDR: Location Dresden and Freiberg (HIF)
• Start date: Either an immediate start or a start in Spring 2025 is possible
• Duration of the internship or thesis according to the study regulations, but at least 4 months
• Remuneration according to HZDR internal regulations, scholarship holders (e.g., ERASMUS+) are welcome

As an important element in batteries, lithium is a critical material for the future energy transition. Derivatives of the alkaloid punicine have been developed with various organic residues to specifically interact with elements such as lithium, or lithium-containing minerals, as surfactants for the upgrading of battery recycling products via flotation separation. Punicine, as a head group, represents a zwitterionic, switchable biomolecule (biosurfactant), in terms of charge via pH and in terms of radical state via UV irradiation potentially influencing its specific interaction with chemical groups or ions. This could be an important factor in ion flotation, which is used to separate ions from battery wastewater. The aim of the project is to investigate this aspect, with a focus on the specific interactions of punicine with lithium ions under the influence of irradiation. Along with ion flotation as the separation method, fundamental investigations such as calorimetry and FTIR will be employed.
We are looking for a motivated student who enjoys working with analytical methods and is eager to explore complex interrelationships.

• Student in, for example, Chemistry, Chemical Engineering, Process Engineering, etc.
• Interest in analytical methods
• First experience in the lab and working with analytical methods (FTIR, Calorimetry, etc.)

• Start date from April 2025 onwards
• Duration of the internship or thesis according to the study regulations, but at least 4 months
• Compensation possible, scholarship holders (e.g., ERASMUS+) are welcome

X-ray fluorescence analysis (XRF) is a standard method to analyse a wide range of elements. Unfortunately, light elements (Z<11) are hard or impossible to analyse using XRF. On the other hand, LIBS (Laser induced breakdown spectroscopy) is able to analyse these elements. Especially the analysis of Lithium in solid samples is an urgent and currently needed topic. We aim to combine the two methods by developing an integrated workflow using fused beads, which is a standard technique for XRF sample preparation, for XRF analysis of the major elements and subsequent LIBS analysis for elements like e.g. Li.
Besides the development of a simple procedure to produce fused beads appropriate for both methods, calibration for both XRF and LIBS have to be implemented. The outcome of this (Master’s, Bachelor’s) thesis should be a as simple as possible workflow (including sample preparation), a sufficient number of reference materials (by e.g. mixing pure components), calibrations for XRF and LIBS, respectively and an evaluation of the desired method’s limitations. Motivated students of analytical chemistry, geosciences or adequate subjects are addressed.