Microstructural, physico-mechanical, optical and photocatalytic characteristics of kaolin-based eucryptite glass ceramics

Lithium aluminosilicates glass ceramics were prepared from quarried kaolin and artificial lithium carbonate. Different techniques were used to characterize the starting batches, glasses and glass ceramics, these are: laser PSDs, XRD, XRF, DSC, SEM-EDAX, bulk density, CTE, microhardness, FTIR, UV-Vis spectrophotometer in addition to Factsage (8.3) thermodynamic modeling software. Results show that the Al/Si ratio and total impurities of kaolin-based batches influence the crystallization of non-cracked and directly bounded coated eucryptite with shielding rims of lithium metasilicates, nepheline, leucite and silicate glassy phase. Notably, the low-grade kaolin-based batch motivates the crystallization of mature lithium aluminosilicate glass ceramics microstructure which enhances the bulk density (2.41 g/cm³), apparent porosity (0.7%), water absorption (0.29%), microhardness (394 kg/mm²), thermal expansion coefficient (₋0.76×10^-7°C^-1) at (25-500°C) and UV-V reflectance up to 86%. The mature microstructure with shielded rimmed eucryptite exhibits outstanding photocatalytic performance, achieving up to 92% removal of MB dye. Such lithium aluminosilicate glass ceramics could be promising in microelectronics and photocatalysis applications.