Fenton-like chain reactions by coupling nanoscale tungsten powders and peroxydisulfate: Performance and mechanistic insights

In this study, Fenton-like chain reaction is constructed by coupling nanoscale tungsten powders (nW⁰) and peroxydisulfate (PDS). The nanoscale tungsten powders/peroxydisulfate (nW⁰/PDS) system exhibits a high oxidation efficiency toward diverse pollutants and expands the effective pH range up to 9.8. Results reveal ^•OH and sulfate radical (SO₄^•-) were confirmed to be responsible for 4,4'-ethylidenebisphenol (EBP) degradation, especially ^•OH. The corrosion process of nW⁰ results in the in-situ production of H₂O₂ and the transient-state tungsten species (W (x, x < VI)), initiating the reaction of H₂O₂ and tungsten species to generate ^•OH. PDS can accelerate nW⁰ corrosion to enhance the Fenton-like reaction, and can be activated by tungsten species (nW⁰ and W (x, x < VI)) to produce ^•OH and SO₄^•-. Integrated the analysis results of LC-QTOF-MS/MS, EBP degradation pathways were proposed. This study reveals the high oxidation efficiency over a wide pH range in the nW⁰/PDS system and provides new insight into the tungsten species induced Fenton-like reaction.