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ION4RAW Partner Gøril Jahrsengene from SINTEF, attended the ECS Conference in Gothenburg last month. This global event drew a remarkable 3,200 attendees and featured a diverse program of 2,427 talks and 1,381 student abstracts. Gøril Jahrsengene made a noteworthy contribution with her presentation titled “Electrochemical Investigations of Ag and Bi in Choline Chloride-Ethylene Glycol DES Electrolyte.”

Her presentation was part of the “Metal Electrodeposition from Fundamentals to Applications” symposium, in the session “Beyond Water.” To explore further details of her work, you can access the abstract and additional information on the ECS Conference website.

Our partner’s active participation at this event reflects the ION4RAW project’s commitment to advancing knowledge and promoting collaboration in the field of raw materials research. Stay tuned for more updates on our ongoing efforts to change the industry.

The ION4RAW project funded by the European Union is investigating innovative recovery processes of metals from different kinds of minerals. The metals of interest are so called “critical raw materials” (CRM) which are globally uneven distributed and mostly imported into the EU. To exploit deposits located within the EU and recover those metals form already processed minerals the ION4RAW project uses deep eutectic solvents (DES) to leach the metals out of ores and minerals. DES are new and environmentally friendly leaching agents made up of organic compounds in contrast to classic water-based leaching agents like acids and bases.

During work package 6 of the ION4RAW project partners from Germany, Italy, Norway and Spain teamed up to transfer the ION4RAW process established in the lab scale to be performed in a pilot plant build, operated and validated at tecnalia research & innovation facilities in Spain. TU Bergakademie Freiberg, Germany, investigated the up-scaling of the process to the medium scale prior to setting up the pilot plant which will be able to process up to 100 L. Working in a jacketed glass reactor of 15 L, displayed in figure 1, suited for that kind of leaching experiments the researchers were able validate the parameters for the process and maintain a high recovery rate of the metals.

Figure 1: Jacketed glass reactor with DES left and during the metal leaching right.

SINTEF in Norway analysed the deposition of the leached metals in solution by applying electrical current for the recovery of pure metals. The Italian partners of RINA Consulting Centro Sviluppo Materiali will evaluate the metals produced during the process in regard to purity and use in commercial products. In the end of the ION4RAW process and products will be validated and evaluated by IDENER in Spain.

Researchers found out that the ION4RAW process can be carried out in a higher processing rate suitable to be performed in early industry applications. Metals of interest like antimony, bismuth or tellurium all of which are important for high-technology products are recovered in high rates from the starting material.

The greatest challenge faced during the up-scaling process was to dissipate the heat produced during leaching. This challenge arises from the different ratios in which volume and surface area change during scale-up. The processed amount of material is in contact with a much lower surface area in large equipment in respect to small lab scale experiments. Therefore, the heat produced can´t be dissipated in such good ways which makes utilisation of sophisticated cooling equipment and agents essential for successful metal recovery.

In the future the ION4RAW process will be applied to other minerals and secondary raw materials like slags from metal production to increase possible application fields of this innovative process. The process should be further optimised and adapted that a broad variety of metals can be recovered and used for production which are currently not recovered for different kinds of mineral deposits and are lost to tailings or landfill. In this way the ION4RAW project will contribute to more environmentally friendly and holistic recovery of metals that are of high importance for industries, consumers and the society in general alike.

In order to develop and evaluate the ION4RAW process on samples from different kind of resources typology and respective mineralogy, five ore deposits were selected and sampled with help of the mining operators: Cobre Las Cruces and El Valle Boinás ore deposits in Spain, Cononish gold mine which is the only active gold mine in Scotland, Cerro Lindo and El Porvenir ore deposits in Peru. Between 300 kg and 7 tons of each bulk ore, totalizing 22.7 tons of material, were sampled during the first year of the project and distributed to ION4RAW partners. Sub-sampling and pre-treatment of the samples for the lab analyses are described in a public report[3].

Author: Ben Ebersbach

WP2 is entitled « By-products potential evaluation » and involved 6 partners of the ION4RAW project and 3 mining operators. It aimed at displaying an extensive and comprehensive evaluation of by-products potential – Bi, Co, Ge, In, Mo, Pt, Re, Sb, Se, Te,  – in Au-Ag, Cu and Cu-Au deposits. Most of these by-product elements belong to the 2020 EU Critical Raw Materials List. Very little data exist about their possible recovery because exploitation and exploration projects mainly focus on the main commodities for economic evaluation.

Location of most favorable areas for epithermal deposits in Europe with higher statistical potential to have enrichment in Sb, Bi, Te, Ge, Se and In (kernel density map)

The first task of WP2 was to produce a geographically-based compilation of the selected by-products occurrences and their relative potential in known European occurrences. The DataBase Querying (DBQ) approach was applied on the historical European Promine dataset. Several areas of great interest for prospection of the targeted by-products of the various mining projects and geological entities were determined. It allows potential identification of commodities, which are either rarely reported in analyses or through divers permit/deposit reports by mining companies. This work may encourage mining operators to search for these rare elements in their deposits / prospects which are located in high potential areas, whereas they are not currently researched. The results are described in detail in a public report[1] and published in a scientific article[2]. They also served as inputs for WP8 to create the Decision Support System.

In order to develop and evaluate the ION4RAW process on samples from different kind of resources typology and respective mineralogy, five ore deposits were selected and sampled with help of the mining operators: Cobre Las Cruces and El Valle Boinás ore deposits in Spain, Cononish gold mine which is the only active gold mine in Scotland, Cerro Lindo and El Porvenir ore deposits in Peru. Between 300 kg and 7 tons of each bulk ore, totalizing 22.7 tons of material, were sampled during the first year of the project and distributed to ION4RAW partners. Sub-sampling and pre-treatment of the samples for the lab analyses are described in a public report[3].

This Back-scattered electron (BSE) image gives evidence of molybdenite (Mo) grains associated with apatite (Apa) in the garnet (Grt) gangue.

After that, a comprehensive characterisation of the ores was necessary to assist the other WP in understanding the link between the ore mineral composition and the potential metal recovery at each step of the ore processing, and optimize process yield. The challenge was to detect and quantify the targeted by-products as they are distributed in highly disseminated trace minerals and in low concentrations among the main ore minerals compared to the main commodities.

Geochemical and mineralogical characterization of the ore samples was performed using multi-scale characterization techniques: whole rock chemistry, X-Ray Diffraction, scanning electron microscopy (SEM and automated mineralogy techniques), micro-X-Ray fluorescence, electron probe microanalyses (EPMA), laser ablation inductively coupled plasma mass spectrometer (LA-ICP-MS). Quantifying all the chemical elements (major, minor and traces) within various ore matrix (massive sulphidic ores or within silicate and carbonate gangue minerals ) is not possible with one single method. Thus, several methods have been applied and adapted to each specific ore-rock samples and respective metal contents and detection limits, depending on the research targeted element, their relative concentrations and their ability to recover them from the solid or solution with the various lab apparatus. The full characterization of each ore sample is described in a confidential report[4], restricted to project partners and the mining operators for strategic and economic reasons.

Micrographs in reflected light of the main galena (Gn)-pyrite (Py)-chalcopyrite (Cpy)-sphalerite (Sph)  ore assemblage with late marcasite replacing garnet. Chalcopyrite essentially occurs as inclusions in sphalerite.

Geochemical and mineralogical characterization served as input for the Life Cycle assessment (WP7). Moreover, the amenability to recover by-products from mineral processing was determined by automated quantitative microscopy analyses using Qemscan and TIMA-X scanning electron microscopic systems. These techniques are applied regularly in the mining industry to quantify the mineralogy of the ore feed and products and it allows understanding the comprehensive deportment of the minerals hosting the targeted by-products. The mineralogical deportment of by-product was statistically analysed as mineral associations, respective form and particle-size distribution of by-product bearing species and assessment of their potential liberation during mineral processing. The results obtained within this task are presented as well in a confidential report[5].

This BSE image shows a pyrite grain where laser ablation was carried out: the holes represent the laser impacts with quite regular morphologies.

Results obtained by WP2 first give to the main stakeholders the areas of interest regarding the targeted by-products. Furthermore, they provide support for the processing industry through assessing the mineralogical deportment of by-products in deferent kind of ores. The methodology applied may be useful to qualify the efficiency of the mineral pre-treatment and will help to predict the potential recovery after hydrometallurgy and DES assays  by comparing the initial ore solid composition with the concentrates and waste compositions after extraction for example or at the successive steps of the process.

[1] Gourcerol B., Bertrand G., Bailly L., Moreau P., Duhamel-Achin I., Négrel P., Warscheid W. (2020), Mapping of by-product potential in mineral deposits – D2.1 ION4RAW H2020 project Grant 815748

[2] Gourcerol B., Bertrand G., Bailly L., Moreau P., Duhamel-Achin I., Picault M., Négrel P. (2022) Predictive assessment of metallogenic signatures using the DataBase Querying (DBQ) method : A European application – Journal of Geochemical Exploration 236

[3] Moreau P., Gourcerol B., Duhamel-Achin I., Delchini S., Négrel P., Warscheid W., Sangster C., Sánchez Ruiz F., Álvarez Cifuentes R., (2020) Technical note and methodology guide for sampling and sample preparation – D2.2 ION4RAW H2020 project Grant 815748

[4] Moreau P., Lerouge C., Bailly L., Gourcerol B., Duhamel-Achin I., Maubec N., Wille G., Lach P., Sangster C., Warscheid W., Álvarez Cifuentes R., Sánchez Ruiz F. (2022) – Chemical and mineralogical characterisation of by- product in target ores – D2.3 ION4RAW H2020 project Grant 815748

[5] Moreau P., Duhamel-Achin I., Bodenan F., Lerouge C. (2023) – Assessment of by- product endowment and metallurgical availability – D2.4 ION4RAW H2020 project Grant 815748

Author: Pauline Moreau

The ION4RAW consortium recently convened in Freiberg, Germany, for their first in-person meeting, marking an important step towards a more sustainable future. This gathering brought together experts and researchers committed to shifting mineral extraction practices and promoting the responsible use of raw materials.

During the three productive days, the consortium members engaged in fruitful discussions, sharing valuable insights and updates on the progress of their work packages. This in person meeting allowed for fruitful discussions and research collaborations, enabling the exchange of ideas and the alignment of efforts towards the project’s common goals.

The highlight of the meeting was the consortium’s visit to Freiberg’s metal mine, an enlightening experience that showcased the innovative practices employed for mineral extraction, the ongoing experiments conducted on-site, and the range of metals being extracted. Witnessing the operations first-hand underscored the significance of responsible mining and the crucial role it plays in achieving a greener and more environmentally conscious future.

The ION4RAW project recognizes the pressing need for a paradigm shift in mineral extraction, aiming to develop innovative techniques that reduce environmental impact while ensuring the efficient utilization of raw materials. By combining expertise from various fields, the consortium strives to unlock new possibilities and drive the transition towards a more sustainable and resource-efficient society. Through ongoing research, development, and collaboration, the ION4RAW consortium seeks to pioneer breakthrough solutions that will help preserve our planet’s precious resources for generations to come.

The TU Freiberg International Centre deserves special recognition for hosting the consortium and providing an ideal platform for knowledge exchange and collaboration.

As the project continues to make significant strides towards sustainable mineral extraction, stay tuned for more updates on the work being done by the ION4RAW consortium.