Centre for Solvometallurgy (SOLVOMET) at KU Leuven Campus Arenberg III in the Leuven Chem&Tech building where dr. Nerea Rodriguez kindly greeted us and took us on a tour of the Centre, showing us the SOLVOMET laboratories and equipment.
SOLVOMET is a Research Centre recently established in prof. Koen Binnemans’ research group (Department of Chemistry, KU Leuven). SOLVOMET’s goal is to support its industrial and RTD partners in the conceptual and practical development of more sustainable solvometallurgical separation processes and new mining chemicals, which are subsequently tested using state-of-the-art lab-scale and mini pilot-scale experimental facilities. More information can be found at the end of the article.
After dr. Nerea Rodriguez provided the necessary protective equipment for the ESRs, the tour started. SOLVOMET facilities, like all the facilities in the L. Chem&Tech building, are separated by three corridors. Two of the corridors are named “clean” corridors (the ones separating the offices from the laboratories) and the third one, which separates two laboratory areas, is named the “technical corridor” (where researchers are required to use their lab coats).
The tour started in one of the laboratories for sample analysis. The group owns a variety of analytical equipment which employ both qualitative and quantitative analytical methods. Such instruments are a UV-Vis-NIR spectrophotometer for analysis of metal and metal-complex solutions, three total reflection X-ray fluorescence (TXRF) spectrometers which are mainly used for quantitative metal analysis of complex samples and a FTIR-Raman spectrometer.
One of the rooms features an ICP-OES analyser, suitable for quantitative analysis of organic and inorganic samples with concentrations up to 50 ppm, and for some elements even in the ppb range. This instrument uses argon plasma allowing the temperature to range from 6000 to 10000 K, which is comparable to the temperature at the surface of the Sun, hence its nickname, Machine of the Sun. The use of this machine must follow a strict schedule as the ventilation of the room works at its full capacity on workdays from 8:00 to 20:00, but that does not stop ambitious researchers of the group who have access to another ICP-OES instrument with non-stop ventilation.
In addition, the room also features Ubbelohde and capillary viscometers and densitometers for measurements of viscosity and density of liquids, along with a moisture analyser.
Every SOLVOMET laboratory is designed for a purpose, so there must be a sample
preparation laboratory with a LeNeo Fluxer for preparing the glass disks for TXRF analysis, multiple analytical balances and a fridge full of calibration solutions for every element.
Another analytical room has a microscope equipped with a camera, an organic elemental analyser (CHN analyser) and a differential scanning calorimetry (DSC) instrument for analysis of phase transitions which, in addition to reaching high temperatures, also enables measurements down to -80 °C. In the room next door, an LCQ Advantage system for LC-MS analysis by direct injection of the sample, coupled to an ELSD detector can be found. This instrument provides a quick and reliable method for analysis of complex mixtures by direct injection of a sample dissolved in an extremely pure solvent followed by ionization and detection with high resolution.
SOLVOMET’s state-of-the-art equipment also features a brand new WDXRF (Bruker S8 TIGER) spectrometer. The wavelength dispersive X-ray fluorescence (WDXRF) analysis can be used to measure the composition of liquid and solid samples. The high resolution of WDXRF provides improved detection limits and sensitivity along with better separation than when using the TXRF, thus samples can be more accurately characterized.
As the tour continued from ground to first floor, the ESRs were shown equipment for sample preparation such as mesh screens and mortar grinders, for better separation of samples of different particle sizes and for further decreasing particle size. The SOLVOMET laboratories are equipped with multiple Schlenk lines for handling air-sensitive compounds and elimination of solvent residues from samples. On the other side of the corridor were two synthesis labs of the SOLVOMET group where every fume hood has specific equipment and therefore a special use. One of the newer SOLVOMET acquisitions are the mixer settlers in various setups for solvent extraction in mineral processing. The last laboratory of the tour features walk-in fume hoods. One of such fume hoods is used for multi-liter leaching reactors for process upscaling. The room is also equipped with multiple mixer-settlers, shakers and a high-pressure reactor for synthesis under higher pressure and temperature.
The tour ended with a brief look at the main chemical storage where compounds are sorted based on their use (solvents, reagents, acids, bases, explosives) and stored in ventilated lockers or refrigerators. The chemicals in the lockers are neatly sorted with respect to the cation of the salt for inorganic compounds and number of carbons and hydrogens for the organic compounds. Next to that, there is also a newly built storage for compounds synthesised by SOLVOMET and the other research groups working in the Chem&Tech building.
The dual mission of the SOLVOMET Centre is (1) to perform excellent research in metallurgical chemistry and to educate and train young researchers in this domain and (2) to support its (industrial and RTD) partners in the conceptual and practical development of more sustainable solvometallurgical and hydrometallurgical separation processes and new mining chemicals, which are subsequently tested using state-of-the-art lab-scale and mini-pilot-scale experimental facilities. The mission of the Centre also includes upscaling the processes and solutions that have been developed on a lab-scale towards a mini-pilot-scale, thus taking Technology Readiness Levels (TRL) from 3-4 to 5-6.
The SOLVOMET research is organized along 4 flagship research domains, with solvent extraction (SX) as a thread through all of them:
- Solvometallurgical and Hydrometallurgical Processes
- Metal Recovery and Separation
- Speciation and Modeling
- Extractant Design and Solvent Formulations