Zn-Fe-CNTs Catalytic in Situ Generation of HO for Fenton-like Degradation of Sulfamethoxazole

A novel Fenton-like catalyst (Zn-Fe-CNTs) capable of converting O to HO and further to OH was prepared through infiltration fusion method followed by chemical replacement in argon atmosphere. The catalyst was characterized by SEM, EDS, TEM, XRD and XPS. The reaction between Zn-Fe-CNTs and O in aqueous solution could generate HO in situ, which was further transferred to OH. The Fenton-like degradation of sulfamethoxazole (SMX) using Zn-Fe-CNTs as catalyst was evaluated. The results indicated that Zn-Fe-CNTs had a coral porous structure with a BET area of 51.67m/g, exhibiting excellent adsorption capacity for SMX, which enhanced its degradation. The particles of Zn and Fe/FeO were observed on the surface of Zn-Fe-CNTs. The mixture of Zn and CNTs could reduce O into HO by micro-electrolysis and Fe/FeO could catalyze in-situ generation of HO to produce OH through Fenton-like process. When initial pH=1.5, T=25°C, O flow rate=400mL/min, Zn-Fe-CNTs=0.6g/L, SMX=25mg/L and reaction time=10min, the removal efficiency of SMX and TOC was 100% and 51.3%, respectively. The intermediates were detected and the possible pathway of SMX degradation and the mechanism of Zn-Fe-CNTs/O process were tentatively proposed.