Comparative Analysis of Cement-Asbestos Materials from Poland and Lithuania: Thermal Decomposition, Mineralogical Characterisation, and Implications for Recycling

Abstract Asbestos-containing cement materials were widely used in construction in the past due to their durability, fire resistance, and thermal insulation properties. However, asbestos is now recognised as a carcinogenic material and has been banned in many countries, including Poland and Lithuania. Asbestos-containing waste is hazardous and requires safe disposal, posing significant environmental challenges. Thermal treatment has been proposed as a potential method for neutralising asbestos and material recycling. In this study, four cement-asbestos samples from Poland (P1, P2) and Lithuania (L1, L2) were investigated to evaluate their chemical composition, mineralogical phases, and thermal behaviour. Samples were characterised using X-ray fluorescence (XRF), X-ray powder diffraction (XRD), differential thermal analysis (DTA), thermogravimetric analysis (TG/DTG), scanning electron microscopy (SEM), and high-temperature microscopy (HTM). Computer simulations of liquid phase formation were performed using FactSage software. The results revealed significant differences between samples from the two countries. Lithuanian materials exhibited higher SiO₂ content and formed liquid phases at lower temperatures, while Polish samples, richer in CaO, showed higher thermal stability and distinct phase evolution. These differences are attributed to variations in raw materials and production methods. The study demonstrates that thermal treatment can effectively transform cementasbestos materials, with the resulting mineral phases and liquid formation influenced by the initial chemical composition. The findings provide valuable guidance for potential recycling strategies of neutralised asbestos waste, offering an environmentally safer approach to asbestos management.