ABSTRACT

Metal–organic frameworks have been extensively studied in catalysis owing to their unique physicochemical properties. However, this class of materials has not yet been directly applied to the catalytic ozonation of organic pollutants. In this study, MIL-100(Fe) was synthesized by a solvothermal method and characterized by powder X-ray diffraction, thermogravimetric analysis, Fourier-transform infrared spectroscopy, N₂ adsorption–desorption and scanning electron microscopy. A range of reaction conditions such as pH, solute concentration and catalyst content were applied to investigate the catalytic activity of our MIL-100(Fe) sample for the ozonation of p-nitrophenol in water. According to the experimental results, at a neutral initial pH, the catalytic ozonation of p-nitrophenol proceeded mainly through radical reactions, whereas in the absence of the MIL-100(Fe) catalyst, ozone could react with p-nitrophenol via the direct reaction pathway. The catalyst achieved a conversion of up to 98% and chemical oxygen demand removal of up to 75%. Moreover, our MIL-100(Fe) catalyst retained this performance for seven cycles of operation, which offers potential applications for metal–organic frameworks as catalysts in wastewater treatment.

摘要

金属-有机框架由于其独特的物理化学性质而在催化领域得到了广泛的研究。然而，这类材料尚未直接应用于有机污染物的催化臭氧化。本研究采用溶剂热法合成了MIL-100(Fe)，并通过粉末X射线衍射、热重分析、傅里叶变换红外光谱、N ₂吸附-脱附和扫描电子显微镜对其进行了表征。应用一系列反应条件（例如 pH 值、溶质浓度和催化剂含量）来研究我们的 MIL-100(Fe) 样品对水中对硝基苯酚的臭氧化的催化活性。根据实验结果，在中性初始 pH 值下，p-的催化臭氧化硝基苯酚主要通过自由基反应进行，而在没有 MIL-100(Fe) 催化剂的情况下，臭氧可以通过直接反应途径与对硝基苯酚发生反应。该催化剂实现了高达 98% 的转化率和高达 75% 的化学需氧量去除率。此外，我们的 MIL-100(Fe) 催化剂在七个操作周期内保持了这种性能，这为金属有机框架作为废水处理催化剂提供了潜在应用。