Role of intrinsic and extrinsic silicon on the structure and adsorption properties of lignin-based spherical porous carbon

The influence of SiO2 on the properties of lignin spherical porous carbon (LSC) was examined. Evidence suggested that the presence of optimal SiO2 contributed to stabilizing the spherical structure of LSC and significantly enhanced LSC’s ability to adsorb antibiotics. Lignin/SiO2 composite microspheres, fabricated through co-precipitation with added sodium silicate, served as precursors for C/SiO2 composite microspheres (LSC-Si(+)). LSC-Si(+) demonstrated excellent adsorption capacity for ciprofloxacin (CIP), sulfadiazine (SDZ), and tetracycline hydrochloride (TC). Furthermore, LSC-Si(+) exhibits excellent physicochemical stability and noteworthy recyclability, maintaining high adsorption capacity after five cycles of recycling. Given the benefits of low cost, ease of production, and excellent adsorption performance, LSC-Si(+)-20 holds promise for removing antibiotic contaminants from wastewater.