Slovak dolomite as a raw material source for metal magnesium production

Abstract

In order to ensure self-sufficiency and a stable supply of essential mineral raw materials within the EU, the European Raw Materials Alliance (ERMA) was established. One of its key objectives is to secure access to sustainable raw materials and support the exploration and mining of these materials within the EU. Metallic magnesium has been included on the list of critical minerals for EU countries since 2011. The most suitable raw materials for Mg production by the silicothermic reduction method are dolomite or magnesite, and the Slovak Republic has considerable resources of these carbonate raw materials. For technological research, six samples of dolomite from different deposits were selected. The samples were annealed at selected temperatures and characterized by differential thermal analysis (DTA), X-ray diffraction (XRD), and chemical analyses. Results published in the conference paper by Danková et al. (2025) showed that for the silicothermic reduction of magnesium, it is necessary to verify the calcination conditions for each sample individually and determine the influence of hydration activity or active sites in their structure to increase magnesium reduction. The selected calcined dolomite samples were subjected to repeated DTA/TG analysis after a two-month interval to determine their hydration. Based on these results, the dolomite sample designated as ST-1, calcined under specified conditions, was used for the laboratory experiment of silicothermic reduction of magnesium. The resulting product was analyzed by SEM/EDX, which detected a high ratio of metallic magnesium (in at. %).