Photocatalysis coupled with adsorption of AC@Ni0.5Cu0.5Fe2O4 in peroxydisulfate assisted system efficiently enhance ciprofloxacin removal

Nickle-copper ferrite (Ni0.5Cu0.5Fe2O4) supported on activated carbon (AC) (AC@Ni0.5Cu0.5Fe2O4) was synthesized and used as adsorbent, photocatalyst, and activator of peroxydisulfate (PDS) to realize the removal of ciprofloxacin (CIP). AC@Ni0.5Cu0.5Fe2O4 properties were characterized by scanning electron microscope equipped with energy-dispersive X-ray (SEM-EDX), X-ray diffraction (XRD), N2 adsorption-desorption isotherm plot of Brunauer-Emmett-Teller (BET) and Barrett-Joyner-Halenda (BJH), vibrating sample magnetometer (VSM). A rapid removal rate (94.30%) of CIP was achieved on AC@Ni0.5Cu0.5Fe2O4/PDS/UV system with the condition of catalyst dosage 0.30 g/L, initial pH 7.3, PDS addition 0.20 mM, CIP concentration 10 mg/L (200 mL), UV 28 W, in 30 min. Free radical quenching experiments indicate that reactive species of superoxide (·O2-), holes (h+), sulfate radicals (SO4-·) and hydroxyl radicals (·OH) were produced and all worked. The reusability test demonstrated that AC@Ni0.5Cu0.5Fe2O4 could be recycled five times with minimal performance reduction for the removal of CIP. The XRD and SEM of the after used AC@Ni0.5Cu0.5Fe2O4 did not change significantly, which further showed its stability and recyclability. This work might provide new insight into the application of AC@Ni0.5Cu0.5Fe2O4 in photocatalysis coupled with adsorption in peroxydisulfate assisted system and has high potential in CIP removal.