Porous biochar activated with KOH and K2CO3: Efficient antibiotic adsorption and antioxidant activity

The extensive presence of pharmaceutical contaminants provides a significant environmental challenge due to their toxicity and endurance in the aquatic environment. In this study, we developed a novel activated biochar (ABC) using a strong base (KOH) and a weak base (K2CO3) through an impregnation method to enhance the yield, surface functionality and adsorption efficiency of the raw biochar (DBC). The synthesized ABC demonstrated outstanding antioxidant properties and significantly developed porosity. Furthermore, this ABC exhibits enhanced removal of antibiotics (ampicillin, AMP; amoxicillin, AMX; and rifampicin, RFP) from wastewater in comparison to raw DBC. Notably, the ABC achieved equilibrium in just 5 min, indicating an extremely rapid adsorption process. The functional groups of ABC and AMP, AMX, and RFP exhibited substantial surface interaction as validated by FTIR. Additionally, ABC exhibited exceptional adsorption efficiency and demonstrated sustainable reusability over seven cycles. Therefore, this study highlights the potential for converting waste into wealth, offering dual benefits for waste management and pollutant remediation. It also helps achieve waste valorization and circular economy goals.