α-FeOOH类Fenton可见光光催化降解有毒有机污染物

α-FeOOH Fenton-like Photodegradation of Toxic Organic Pollutants

用氨水滴定法制备了针铁矿α-FeOOH,以α-FeOOH作为光催化剂,橙Ⅱ(Orange-Ⅱ)和2,4-二氯苯酚(2,4-dichlorophenol,DCP)为目标化合物,研究了可见光照射下(λ>420 nm)α-FeOOH对其光催化降解的催化特性。结果表明:在可见光照射下,pH为7.02,H2O2浓度为1.5×10-2 mol/L,α-FeOOH用量400 mg/L条件下,对橙II的降解效果最好,17 h橙Ⅱ的矿化率达到51%。光照390 min后DCP降解率达67.5%。通过对光催化降解体系溶液中铁离子的测定,铁离子的最高量为1.029 mg/L,说明可能的反应机理为针铁矿表面的铁循环。采用苯甲酸荧光分析法测定体系中氧化物中羟基自由基的含量,表明光催化降解过程主要涉及.OH历程。

Gothite was synthesized with AT method.Under visible light,the degradation of Orange-II and 2,4-dichlrophenol（DCP） was investigated with goethite as catalyst.Results showed that the optimum operation parameters as neutral pH 7.02,H2O2 and goethite 1.5×10-2 mol/L and 400 mg/L respectively under visible light,after 17 h,the rate of mineralization was 51%,DCP degraded by 67.5% after 390 min under visible light.Dissolved iron was determined in the photocatalytic system,with the highest amount as 1.029 mg/L,which indicated that the possible mechanism was iron circulation on the surface of goethite..OH radical concentration was indirectly detected utilizing benzoic acid by fluorescence analysis method,which showed photocatalytic degradation mainly referred to.OH radical mechanism.