Increase in CO2 emissions, due to intensive use of fossil fuels as an energy source, in industry and transportation, has contributed to global warming. One of the proposed solutions for CO2 storage is mineral carbonation in carbonate minerals in ultramafic rocks to obtain stable secondary magnesite. Two different types of serpentinite rock from Pohorje Mts., from Radkovec and Bistriški vintgar, were investigated to determine potential for industrial CO2 sequestration. Mineral and chemical composition of serpentinite rocks were determined with optical microscopy, X-ray diffraction (XRD) and X-ray fluorescence analysis (XRF). Samples were crushed, finely grinded and preheated. Three sets of experiments, under different conditions, were carried out for samples from both locations to determine the most economically feasible conditions. Firstly at ambient temperature, secondly at 95 °C and thirdly at 95 °C with an addition of NaHCO3. Following the experiments, products were analyzed with raman spectroscopy, XRD powder diffraction and scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDS). Results showed that under selected conditions reactions occurred to a lesser degree. Due to this, we could not reliably measure the quantity of newly formed magnesite as the conversion was too small. We proved that the reaction occurs at ambient temperatures, but it is very slow. In second and third set of experiments reactions did not occur. Considering the results, the amount of magnesium in high-temperature minerals (olivine and orthopyroxene) in serpentinite rock types from Pohorje is too low, therefore selected samples and conditions are not suitable for industrial mineralization of CO2.
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