Degradation of antibiotics by homogeneous and heterogeneous Fenton processes: A review

Global antibiotic consumption has been rising uncontrollably. Antibiotics ultimately get flushed into the environment, where they can pose risks to ecosystems and human health. Conventional wastewater treatment processes are not effective at removing these antibiotics. However, the application of Fenton processes in water treatment has attracted attention due to their fast reaction speeds and effective performances. Here we review recent research related into Fenton processes for antibiotic degradation, including homogeneous and heterogeneous Fenton, photo-Fenton and electro-Fenton reactions. We look at the impact of several key parameters such as target antibiotic, hydrogen peroxide, ferrous ion concentrations, pH and temperature on the efficiency of antibiotic degradation. We also provide an in-depth analysis of commonly used catalysts, such as natural heterogeneous catalysts and synthetic iron-based catalysts, and go on to propose typical mechanisms for antibiotic degradation by homogeneous and heterogeneous Fenton processes based on products identified in the literature.