Enhanced sulfamethoxazole degradation in aqueous media using a synergistic system with dielectric barrier discharge plasma, biochar-enriched iron concentrate, and persulfate

The synthesis of biochar-based catalysts from bamboo strip biomass waste aligns with the principles of environmental sustainability and recycling. This study focuses on the degradation of sulfamethoxazole (SMX) in a simulated aqueous environment. A composite catalyst (IC–BC) was prepared by impregnating bamboo strip biochar (BC) with iron concentrates (IC). The optimal configuration for the oxidative degradation of SMX was achieved using IC-BC-activated persulfate (PS). The structural, morphological, optical, and electrochemical properties of the IC-BC were thoroughly characterized, revealing its robust stability through repeated cycles. The dielectric barrier discharge (DBD) synergistic IC-BC/PS oxidation system demonstrated an SMX degradation efficiency of 93.33 % in 10 min. Quenching experiments and electron paramagnetic resonance (EPR) spectroscopy identified radicals O• − 2 , • OH, and SO• − 4 radicals as the primary active species involved in the degradation process. Ultraviolet-visible absorption spectroscopy (UV–Vis) confirmed this synergistic effect. Liquid chromatography mass spectrometry (LC-MS) identified four potential SMX degradation pathways. Total Organic Carbon (TOC) elimination efficiency tests and toxicological analyses revealed that the intermediates were significantly less toxic than SMX. These results demonstrate that the DBD/IC-BC/PS system significantly enhances the removal efficiency of SMX, offering excellent environmental protection properties.