Antipovych Y., Shvaika I., Kunecki P. Geochemical characteristics of rare earth element distribution in coal combustion products
- Details
- Parent Category: Geo-Technical Mechanics, 2025
- Category: Geo-Technical Mechanics, 2025, Issue 175
Geotech. meh. 2025, 175, 133-140
https://doi.org/10.15407/geotm2025.175.133
GEOCHEMICAL CHARACTERISTICS OF RARE EARTH ELEMENT DISTRIBUTION IN COAL COMBUSTION PRODUCTS
1M.S. Poliakov Institute of Geotechnical Mechanics of the National Academy of Sciences of Ukraine
2M.P. Semenenko Institute of Geochemistry, Mineralogy and Ore Formation of the National Academy of Sciences of Ukraine
3Mineral and Energy Economy Research Institute, Polish Academy of Sciences
UDK 662.613.002.84:621.311.22
Language: English
Abstract. The study presents an integrated morphological and geochemical characterization of coal combustion products from the Prydniprovska Thermal Power Plant, with the aim of assessing their potential as secondary sources of rare earth elements (REEs). The samples of fly ash, boiler slag, and bottom ash were examined using scanning electron microscopy coupled with energy-dispersive spectroscopy (SEM-EDS) and inductively coupled plasma mass spectrometry (ICP-MS). SEM-EDS results revealed that the investigated materials are mainly composed of amorphous and cryptocrystalline aluminosilicates, glassy phases, and numerous cenospheres containing mineral inclusions and agglomerates. Such microstructural features indicate rapid cooling of the molten material and provide favorable conditions for REE accumulation within the fine-grained aluminosilicate matrix.
The ICP-MS data show significant differences in REE concentrations among the analyzed products. The highest total REE contents were detected in fly ash (Ce – 150.6 ppm, Nd – 77.4 ppm, La – 64.9 ppm, Y – 50.7 ppm), followed by lower values in boiler slag and bottom ash. Chondrite-normalized REE distribution patterns exhibit a pronounced enrichment in light REEs (LREE/HREE = 2.48–2.60) and high (La/Yb)_N ratios (6.23–7.56), indicating strong fractionation between light and heavy elements. All samples display a negative Eu anomaly (Eu/Eu* = 0.64–0.72), most distinct in the bottom ash, which is likely related to the incorporation of Eu²⁺ into feldspar-group minerals during high-temperature combustion.
The integration of SEM-EDS and ICP-MS results demonstrates consistent morphological and geochemical trends, highlighting fly ash and boiler slag as the most promising fractions for REE recovery. These findings emphasize the importance of coal combustion residues as a valuable source of critical raw materials and contribute to the development of sustainable strategies for waste utilization and resource diversification in Ukraine’s post-war energy sector. The obtained data can serve as a sustainable basis for the development of effective technological solutions for processing coal combustion products, taking into account economic and environmental feasibility.
Key words: thermal power plant, solid wastes, rare earth elements, critical raw materials, recycling of by-products
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About the authors
Antipovych Yana, Candidate of Geology (Ph.D), Senior Researcher, The Laboratory for the Study of Structural Changes in Rocks, M.S. Poliakov Institute of Geotechnical Mechanics of the National Academy of Sciences of Ukraine (IGTM of the NAS of Ukraine), Dnipro, Ukraine, This email address is being protected from spambots. You need JavaScript enabled to view it. (Correspondingauthor), ORCID 0000-0002-7929-9599
Shvaika Ihor, Junior Researcher, The Department of Isotope Geochemistry and Mass Spectrometry, M. P. Semenenko Institute of Geochemistry, Mineralogy and Ore Formation of the National Academy of Sciences of Ukraine (IGMR of the NAS of Ukraine), Kyiv, Ukraine, This email address is being protected from spambots. You need JavaScript enabled to view it. , ORCID 0000-0002-1908-6639
Kunecki Piotr, Ph.D., Eng., Assistant Professor, The Department of Circular Economy, Mineral and Energy Economy Research Institute, Polish Academy of Sciences (MEERI PAS), Krakow, Poland, This email address is being protected from spambots. You need JavaScript enabled to view it. , ORCID 0000-0002-9890-4635