*Proceeding Paper* **Characterization of a Coal Shale from Marcel Mining as Raw Material for Geopolymer Manufacturing †**

**Kinga Korniejenko 1,\* , Beata Figiela <sup>1</sup> , Kinga Pławecka <sup>1</sup> , Alperen Bulut <sup>2</sup> , Baran ¸Sahin 2, Göksu Aziza ˘gao ˘glu <sup>2</sup> and Michał Łach <sup>1</sup>**


**Abstract:** Implementing the idea of a circular economy is one way to reduce carbon emissions and, at the same time, the consumption of natural resources. The use of mining waste as a raw material helps meet the growing demand for construction materials with a smaller carbon footprint. The article shows the possibility of using a coal shale from Marcel mining to create new eco-friendly materials, geopolymers. The main aim of the presented research includes characteristics of raw material and synthesis of geopolymers based on mining waste (coal shale from Marcel mining) and next, investigations of the obtained materials. Geopolymer was prepared using a sodium activator plus milled and calcinated precursor materials. In this study, the following research methods were used: particle size analysis, XRD analysis, mechanical properties tests (compressive and bonding strength), and microstructure analysis—scanning electron microscopy. The results show potential for the extraction of waste from the Marcel company to obtain material for advanced applications in the geopolymerization process. The material had a compressive strength of 12.7 MPa and a bending strength of 3.4 MPa, which makes it possible for use in construction applications such as various types of foundations, walls, columns, lintels, terraces, stairs, ceilings, small building elements, and small architecture. The proposed process could be a promising alternative to current methods of managing waste rock, in particular hard coal mining.

**Keywords:** geopolymer; coal shale; mining waste; industrial by-products; circular economy
