The non-radical pathway is a subject of interest due to its selective oxidation of pollutants and low use of oxidants. The graphitized structure of carbon enhances the non-radical pathway of electron transfer, facilitating the activation of peroxydisulfate (PDS). Defects are commonly considered the primary cause of increased adsorption, while excessive graphitization may impede adsorption properties. Acid is frequently employed for introducing defects owing to its superior etching characteristics. This study challenges the conventional understanding and investigates the pivotal role of acid in the development of graphitized structures. The degree of graphitization of carbon materials was adjusted through impregnation pyrolysis in conjunction with acid-induced pore formation. Highly graphitized, nitrogen-containing porous sludge biochar (HGSB) was produced at 600 degrees C through pyrolysis, and degradation of ofloxacin (OFX) was carried out using activated PDS. Through a synergistic combination of adsorption and degradation (exhibiting an adsorption capacity 9.03 times higher than that of the inactivated material), HGSB achieved complete OFX removal under optimal conditions, where 1 O 2 and electron transfer played a significant role. The primary active sites identified were graphite N, pyridinic N, C=O, and C=C. Electrochemical analyses indicated that increased graphitization could shift the radical pathway of sludge biochar towards the non-radical pathway. Pearson correlation analysis was utilized to explore the relationship between the degree of graphitization and degradation rate constants, functional group types, and other factors. Additionally, three degradation pathways were elucidated through HPLC-MS, and the toxicity of the intermediates was assessed using TEST software simulations and E. coli culture experiments, demonstrating the environmental sustainability of HGSB/PDS.
