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以硝酸铁为铁源、氢气为还原气,采用氢氛还原法制备了Fe3O4/膨润土.利用X射线衍射、扫描电子显微镜和电子能谱对Fe3O4/膨润土进行表征分析,并考察了影响类Fenton催化降解金橙Ⅱ的因素,初步探讨了催化作用机理.结果表明,铁化合物有效固载在膨润土并转化为Fe3O4,所得Fe3O4/膨润土结构分散、孔隙明显、物化形态优良;在反应温度30℃、Fe3O4/膨润土投加量0.4 g/L、H2O2投加量10 mmol/L、初始pH 3的优化条件下,质量浓度40mg/L的金橙Ⅱ在lh内去除率达到98.1％;Fe3O4/膨润土重复使用3次效果稳定,铁离子溶出量低,H2O2在膨润土所固载Fe3O4的Fe2+、Fe3+作用下产生羟基自由基(·OH),高活性的·OH将金橙Ⅱ氧化降解.“,”Fe3O4/bentonite was prepared by hydrogen atmosphere reduction using bentonite and ferric nitrate as raw materials,and the Fe3O4/bentonite was characterized by XRD,SEM and EDS.Factors which would affect Fenton-like catalytic degradation of Orange Ⅱ was investigated,and the catalytic mechanism of Fe3O4/bentonite was preliminarily discussed.The results showed that the iron compounds were effectively immobilized on bentonite and converted to Fe3O4 by hydrogen reduction during preparation process,and the prepared Fe3O4/bentonite was a catalytic material with decentralized structure,obvious pores and excellent morphology.The degradation ratio of 40 mg/L mass concentration of Orange Ⅱ reached 98.1％ under the conditions of reaction temperature 30 ℃,Fe3O4/bentonite catalyst dosage 0.4 g/L,H2O2 dosage 10 mmol/L,solution pH 3,and reaction time 1 h.The Fe3O4/bentonite catalyst showed good stability and low iron leaching amount after 3 recycles.The Fe2+ and Fe3+ provided by Fe3O4 immobilized on bentonite could catalyze H2O2 to produce hydroxyl radicals (·OH),and · OH had a strong oxidative capability to degrade oxidatively the Orange Ⅱ.