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In light of the European Union’s energy transition strategy aimed at minimizing dependence on fossil fuels, hydrogen has emerged as a key non-carbonaceous reducing agent, offering significant potential for application in metallurgical processes. This study focuses on the material characterization of selected high-grade manganese ores and evaluates their suitability for hydrogen-based reduction. The investigated samples originated from Burkina Faso, Gabon, Ghana, and South Africa—regions known for some of the highest-quality manganese deposits globally. Material testing included chemical, mineralogical, physical, and thermal property analyses, with an emphasis on reducibility. The effectiveness of hydrogen reduction largely depends on the oxidation state of manganese in the ores. Ores rich in MnO₂, such as those from Gabon, demonstrated the highest suitability due to the favorable reduction path to MnO. Gabonese ore, dominated by porous pyrolusite and with low SiO₂ content, showed promising characteristics for low-temperature hydrogen reduction (below 500 °C). In contrast, ores from South Africa and Ghana, which contain manganese primarily in carbonate form (rhodochrosite), exhibited lower potential for hydrogen-based processing. These ores are more suitable for carbothermal reduction, as the dissociation of MnCO₃ to MnO does not align with hydrogen reduction pathways. Overall, the study confirms that mineralogical composition—specifically the presence of higher manganese oxides—plays a critical role in determining the feasibility of hydrogen utilization in manganese ore reduction. The findings support the selection of specific ore types for further thermodynamic simulations and experimental work in the development of low-emission metallurgical technologies.
Keywords: Hydrogen-reduction, manganese ore, reduction treatment, mineralogical characterization© This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.