SYNTHESIS, PHASE COMPOSITION AND PHYSICAL-CHEMICAL PROPERTIES OF MULLITE-CORDIERITE REFRACTORY CERAMICS BASED ON WASTE ALUMINUM DROSS AND MgO

Abstract

In the present work, mullite-cordierite refractory ceramics were synthesized by partially replacing chamotte (10% and 20%) with waste aluminum dross and MgO in the MgO–Al2O3–SiO2 system. The influence of sintering temperature (1250 °C and 1350 °C) and holding time (1h and 3h) on the phase composition, microstructure and physical properties was studied. X-ray phase analysis revealed that at 1350 °C indialite (a high-temperature analogue of cordierite) is formed as the main Mg-aluminosilicate phase, and its reflections become more pronounced with increasing the MgO content and temperature. The presence of residual quartz and cristobalite was found, which indicates incomplete solid-state reactions due to the heterogeneity of the waste raw materials. The sample with 20 mass% substitution (M2) has a lower apparent density (1.95–2.10g/cm3) and higher porosity (22.03–26.16%) compared to M1 (10 mass% waste replacement), due to the volumetric expansion during the synthesis of indialite. The results demonstrate the possibility of valorization of waste aluminum dross in the production of mullite-cordierite refractories. For citation: Kolchakova G.R., Khristov Ya.H. Synthesis, phase composition and physical-chemical properties of mullite-cordierite refractory ceramics based on waste aluminum dross and MgO. ChemChemTech [Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.]. 2026. V. 69. N 10. P. 84-93. DOI: 10.6060/ivkkt.20266910.7361.