Facile ball milling preparation of sulfur-doped carbon as peroxymonosulfate activator for efficient removal of organic pollutants

Novel sulfur-doped activated carbon (SACx) particles were prepared by a facile ball milling process of a mixture of elemental sulfur and activated carbon (AC), and employed as activators of peroxymonosulfate (PMS) for the degradation of organic pollutants. The SACx/PMS system could efficiently degrade different pollutants including diethyl phthalate, bisphenol A, sulfamethoxazole, and phenol, achieving a degradation efficiency of 60-100% within 120 min. Increasing the S doping content favored PMS activation and pollutant degradation: the DEP degradation rate increased by 9 times as the S-doped content increased from 0 to 8.69 at%. EPR and radical quenching experiments suggested that (OH)-O-center dot rather than SO4 center dot- was the dominant reactive species for DEP degradation. The concentration of free radicals was strongly dependent on the content of C-S-C bonds, indicating that these linkages were the main active sites for PMS activation. This study provides a simple but effective strategy to improve the catalytic performance of carbon-based materials as PMS activators to degrade pollutants.

Automated summary

Novel sulfur-doped activated carbon particles were prepared through a simple method and utilized as activators of PMS to efficiently degrade various organic pollutants, with the degradation efficiency being dependent on the S doping content. The study showed that the presence of C-S-C bonds significantly influenced the degradation rate of pollutants like DEP, suggesting their importance in PMS activation.