Facile synthesis of SrWO4@MIL-88A(Fe) heterojunctions and their deep treatment of dye wastewater and municipal landfill leachate using photo-Fenton technology

Abstract

Dye wastewater and municipal landfill leachate greatly threaten the ecological environment and human health. We prepared SrWO4@MIL-88A(Fe) composites in this work by room temperature synthesis. A systematic degradation study of methylene blue (MB) and landfill leachate was carried out using the photo-Fenton process. The results showed that SrWO4@MIL-88A(Fe) could degrade 93.75 % of MB within four min. Within 15 min of sunlight irradiation, SrWO4@MIL-88A(Fe) could degrade up to 95 % of MB. It could eliminate up to 87.19 % of COD, 90.23 % of BOD5, 99.50 % of TOP- P, 80.96 % of TOP-N, and 81.48 % of NH3-N in the leachate. The toxicity of the deep-purified leachate is significantly reduced, and alfalfa seeds can use the remaining organic matter in the leachate to germinate and grow, thus achieving self-purification of the detoxified leachate. In addition, the photo-Fenton technology can effectively kill the bacterial microorganisms in the leachate and reduce the epidemiological hazard to organisms. In conclusion, the photo-Fenton process of SrWO4@MIL-88A(Fe) provides a purification pathway for the dual-effect treatment of MB and municipal landfill leachate.