In this study, coal bottom ash particles were modified through high-energy ball milling and evaluated for the removal of methyl violet 10B (MV) dye from aqueous environment via the adsorption process. The presence of a partially amorphous structure with nano- and submicron particles, containing silanol group (Si-OH), along with higher surface area and pore volume values compared to the unmodified sample, was confirmed by different characterization methods, including X-ray diffractometry (XRD), Fourier transform infrared spectroscopy (FTIR), BET analysis, scanning electron microscopy (SEM/EDS), and laser granulometry. These characteristics provided an appreciable adsorptive activity to the modified material, achieving an adsorption capacity of 27.17 mg g