Impact of solvent-free ball milling on sulfur dissolution in groundwater simulants

• Water with high sulfur could be reactive and degrade pollutants. • Grande Comore’s groundwater has worrisome high sulfur levels. • Ball milling modifies sulfur, enhancing dissolution of radical species. • Low sulfur dissolution in acidic solutions affects groundwater. • Rainwater significantly influences sulfur dissolution. • Ball milling activates sulfur, enhancing its solubility to 807 ppm in water and revealing the monoclinic beta phase (S-β). Sulfur, the fifteenth most abundant element in the Earth’s crust, was activated through solvent-free ball milling to investigate its dissolution behavior and environmental implications. This study evaluated the influence of grinding conditions on sulfur’s phase transformation and solubility in different solvents. X-ray diffraction (XRD) analysis revealed a significant phase transition to the monoclinic β-sulfur phase (S-β) at a grinding speed of 500 rpm. Remarkably, sulfur solubility reached 807 ppm in water, compared to only 18.6 ppm in an acidic medium, underscoring the importance of solvent chemistry. Additionally, the activated sulfur exhibited self-photocatalytic activity, generating highly reactive oxidizing species crucial for the degradation of Methyl Orange (MO) dye, highlighting its potential for wastewater treatment. Advanced characterization techniques such as scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FT-IR) provided insights into the dissolution mechanisms. This study demonstrates the transformative potential of mechanically activated sulfur in environmental remediation and lays the foundation for future research on sustainable water treatment solutions.