This study examines the efficacy of geopolymer composites derived from metakaolin (MK) and waste glass wool (GW) in the removal of methylene blue (MB) from aqueous solutions. For characterization, X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), Scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDX), and Brunauer-Emmett-Teller (BET) analysis were performed. The results showed that adding more GW made the surface rougher, more porous, and higher specific surface area. The sample made entirely of GW had a specific surface area of 268.35 m2 g-1. Structural analyses corroborated the emergence of calcium-aluminosilicate gel phases in GW formulations. Adsorption performance was closely related to the gel's surface area and composition. The 100 GW and 20-80 MK-GW samples had the highest removal efficiency. Kinetic studies showed that the pseudo-second-order model best described the process, indicating that chemisorption was the predominant mechanism. Regeneration experiments showed that stability was achieved, with more than 80% of the capacity remaining after two cycles. Overall, these results highlight GW-based geopolymers as sustainable and low-cost adsorbents for effective dye removal.
Cansu Kurtuluş (2026) studied this question.