Effect of Some Synthetic Factors on the Metal-organic Framework Formation of MIL-53(Fe) and its Catalytic Activity in Fenton-like Reaction System

Abstract

The iron (III) benzene dicarboxylate metal-organic framework material (MIL-53(Fe)) has been synthesized and used as a catalyst for the decomposition of organic pollutants in aqueous solution by hydrogen peroxide. The effects of different solvents, including N',N-dimethylformamide (DMF), methanol (MeOH), and water, on the formation of the metal-organic framework of the materials were investigated. The influence of the molar ratio of precursors and DMF solvent, temperature, and reaction time on the structure of MIL-53(Fe) was also addressed. The MIL-53(Fe) structure formed in DMF solvent, and MeOH solvent but not in water. In DMF solvent, the molar ratio of precursors and solvent, temperature, and reaction time had a significant effect on the crystal structure of MIL-53(Fe). Under optimal conditions, MIL-53(Fe) has high crystallinity and a large specific surface area (S_BET = 88.2 m²·g^-1). The obtained MIL-53(Fe) was used to activate hydrogen peroxide in the Fenton-like reaction system to decompose phenol (PhN), rhodamine B (RhB), and methylene blue (MtB) at the different solution pHs. The results showed that MIL-53(Fe) could effectively act as a heterogeneous catalyst over a wide pH range (from 2 to 12). Therefore, MIL-53(Fe) could be used to treat wastewater contaminated by organic substances.