Sulfate Radical-Based Degradation of Organic Pollutants: A Review on Application of Metal-Organic Frameworks as Catalysts

The degradation of organic pollutants present in domestic and industrial effluents is a matter of concern because of their high persistence and ecotoxicity. Recently, advanced oxidation processes (AOPs) are being emphasized for organic pollutant removal from effluents, as they have shown higher degradation efficiencies when compared to conventional activated sludge processes. Sulfate radical-based methods are some of the AOPs, mainly carried out using persulfate (PS) and peroxymonosulfate (PMS), which have gained attention due to the ease of sulfate radical generation and the effective degradation of organic molecules. PMS is gaining more popularity because of its high reactivity and ability to generate excess sulfate radicals. PMS has been the major focus; therefore, its mechanism has been explained, and limitations have been elaborated. The involvement of metal-organic frameworks for PMS/PS activation applied to organic pollutant removal and recent advances in the application of biochar and hydrogel-assisted metal-organic frameworks have been discussed.