Iron-based biochar as efficient persulfate activation catalyst for emerging pollutants removal: A review

In recent years, biochar (BC) as a low-cost, easily available biomass product, is widely applied in sulfate radical-based advanced oxidation processes (SR-AOPs) for emerging pollutants remediation. Herein, a state-of-art review of iron-based biochar catalysts is currently available in SR-AOPs application. A general summary of the development of biochar and the catalytic properties of biochar is presented. Especially, the synthetic strategies of different types of iron-based biochar catalysts are discussed. Moreover, the theoretical calculation to interpret the interaction between biochar and iron species is discussed to explore the activation mechanisms. And the regeneration methods of biochar-based catalyst are presented. The unresolved challenges of the existent biochar-based SR-AOPs are pointed out, and the outlooks of future research directions are proposed.