Degradation of tetracycline hydrochloride by heterogeneous Fenton-like reaction using Fe@Bacillus subtilis

A novel heterogeneous catalyst Fe@Bacillus subtilis has been synthesized though the impregnation method with iron(III) chloride hexahydrate. Field emission scanning electron microscopy (FE-SEM), energy dispersive spectrometry (EDS), energy dispersive X-ray (EDX) mapping, X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FT-IR) were used to characterize the materials. The as-prepared materials were employed as a heterogeneous Fenton's reagent with the addition of H2O2 for degradation of tetracycline hydrochloride (TC). This new heterogeneous Fenton-like system resulted in nearly complete elimination of TC and negligible release of iron leaching from the catalyst was achieved. The catalytic performance could be maintained in three consecutive runs without a significant drop. This behavior was attributed to the synergistic structural and functional effect of the combined B. subtilis and iron ions. The FTIR and XPS characterizations of the catalyst before and after the Fenton-like reaction showed that no structural deformation of the particles occurred.