Removal of sulfamethoxazole (SMX) and sulfapyridine (SPY) from aqueous solutions by biochars derived from anaerobically digested bagasse

This study explored the sorption of sulfamethoxazole (SMX) and sulfapyridine (SPY) onto biochars produced from raw and anaerobically digested bagasse. Initial evaluation of six bagasse biochars showed that digested bagasse biochar prepared at 600 °C (DBG600) was the best adsorbent to remove SMX and SPY. Further laboratory batch sorption experiments showed that DBG600 adsorbed SMX and SPY from aqueous solution with maximum adsorption capacity of 54.38 and 8.60 mg g⁻¹, respectively. Solution pH showed strong effect on the sorption ability of DBG600 to the two antibiotics, and the sorption decreased with increasing of solution pH. Experimental and model results suggested that adsorption of SMX and SPY onto DBG600 might be controlled by the π–π interaction.